1990 BMW 5 SERIES heat

On some models, it will be necessary to
release the retaining clip (see illustration).
13Visually examine the canister for leakage
or damage.
14Renew the canister if you find evidence of
damage or leakage.
7 Catalytic converter
1
General description
1To reduce emissions of unburnt
hydrocarbons (HC), carbon monoxide (CO)
and oxides of nitrogen (NOx), the later
vehicles covered by this manual are equipped
with a catalytic converter (see illustration).
The converter contains a ceramic honeycomb
coated with precious metals, which speed up
the reaction between the pollutants listed
previously and the oxygen in the exhaust gas.
The pollutants are oxidised to produce water
(H
2O), nitrogen and carbon dioxide (CO2).
Check
2Visually examine the converter(s) for cracks
or damage. Make sure all nuts and bolts are
tight.
3Inspect the insulation cover (if applicable)
welded onto the converter - it should not be
loose.
Caution: If an insulation cover is
dented so that it touches the
converter housing inside,
excessive heat may be
transferred to the floor.
4Start the engine and run it at idle speed.
5Check for exhaust gas leakage from the
converter flanges. Check the body of each
converter for holes.
Component renewal
6See Chapter 4 for removal and refitting
procedures.
Precautions
7The catalytic converter is a reliable and
simple device, which needs no maintenance
in itself, but there are some facts of which an
owner should be aware, if the converter is to
function properly for its full service life.
(a) DO NOT use leaded (eg UK “4-star”)
petrol in a car equipped with a catalytic
converter - the lead will coat the precious
metals, reducing their converting
efficiency, and will eventually destroy the
converter.
(b) Always keep the ignition and fuel systems
well-maintained in accordance with the
manufacturer’s schedule, as given in
Chapter 1. In particular, ensure that the air
cleaner filter element, the fuel filter (where
fitted) and the spark plugs are renewed at
the correct interval. If the intake air/fuel
mixture is allowed to become too rich due
to neglect, unburned fuel will enter the
catalytic converter, overheating the
element and eventually destroying the
converter.
(c) If the engine develops a misfire, do not
drive the car at all (or at least as little as
possible) until the fault is cured - the
misfire will allow unburned fuel to enter
the converter, which will result in its
overheating, as noted above.
(d) DO NOT push- or tow-start the car - this
will soak the catalytic converter in
unburned fuel, causing it to overheat
when the engine does start - see (b) or (c)
above.
(e) DO NOT switch off the ignition at high
engine speeds - ie do not “blip” the
throttle immediately before switching offthe engine. If the ignition is switched off
at anything above idle speed, unburned
fuel will enter the (very hot) catalytic
converter, with the possible risk of its
igniting on the element and damaging the
converter.
(f) DO NOT use fuel or engine oil additives -
these may contain substances harmful to
the catalytic converter.
(g) DO NOT continue to use the car if the
engine burns oil to the extent of leaving a
visible trail of blue smoke - the unburned
carbon deposits will clog the converter
passages, and reduce its efficiency; in
severe cases, the element will overheat.
(h) Remember that the catalytic converter
operates at very high temperatures -
hence the heat shields on the car’s
underbody - and the casing will become
hot enough to ignite combustible
materials which brush against it. DO NOT,
therefore, park the car in dry
undergrowth, or over long grass or piles
of dead leaves.
(i) Remember that the catalytic converter is
FRAGILE - do not strike it with tools
during servicing work, and take great care
when working on the exhaust system.
Ensure that the converter is well clear of
any jacks or other lifting gear used to raise
the car, and do not drive the car over
rough ground, road humps, etc, in such a
way as to “ground” the exhaust system.
(j) In some cases, particularly when the car
is new and/or is used for stop/start
driving, a sulphurous smell (like that of
rotten eggs) may be noticed from the
exhaust. This is common to many
catalytic converter-equipped cars, and
seems to be due to the small amount of
sulphur found in some petrols reacting
with hydrogen in the exhaust, to produce
hydrogen sulphide (H
2S) gas; while this
gas is toxic, it is not produced in sufficient
amounts to be a problem. Once the car
has covered a few thousand miles, the
problem should disappear - in the
meanwhile, a change of driving style, or of
the brand of petrol used, may effect a
solution.
(k) The catalytic converter, used on a well-
maintained and well-driven car, should
last for 50 000 to 100 000 miles - from
this point on, the CO level should be
carefully checked regularly, to ensure that
the converter is still operating efficiently. If
the converter is no longer effective, it
must be renewed.
6•6 Engine management and emission control systems
7.1 Typical catalytic converter (M10
engine type shown, others similar)6.12 EVAP system charcoal canister
viewed from under the vehicle (316i model)

adjusting screw and contract the handbrake
shoes (see illustration).
Refitting
7Ensure that the disc is completely clean
before refitting. If penetrating oil was used to
remove the disc, make sure that no trace of
this is present. Place the disc on the hub, and
refit the disc retaining screw. Tighten the
screw securely.
8Refit the caliper mounting bracket (if
removed), brake pads and caliper (see
Sections 3 and 4). Tighten all fasteners to the
torques listed in this Chapter’s Specifications.
9Refit the wheel, then lower the vehicle to
the ground. Depress the brake pedal a few
times to bring the brake pads into contact
with the disc.
10Adjust the handbrake shoes, if necessary
(Section 11).
11Check the operation of the brakes
carefully before returning the vehicle to
normal service.
6 Drum brake shoes- renewal
2
Warning: Brake shoes must be
renewed on both wheels at the
same time - never renew the
shoes on only one wheel. Also,
the dust created by the brake system may
contain asbestos, which is harmful to your
health. Never blow it out with compressed
air, and don’t inhale any of it. Always wear
an approved filtering mask when servicing
the brake system. Do not, under anycircumstances, use petroleum-based
solvents to clean brake parts. Use brake
system cleaner only.
Caution: Whenever the brake
shoes are renewed, new return
and hold-down springs and new
automatic adjuster thermo-clips
should also be fitted. Due to the
continuous heating/cooling cycle to which
the springs are subjected, they may lose
their tension over a period of time,
allowing the shoes to drag on the drum,
and wear at a much faster rate than
normal. When fitting new brake shoes, use
only original-equipment or high-quality
brand name parts.
Note 1:All four rear brake shoes must be
renewed at the same time, but to avoid mixing
up parts, work on only one brake assembly at
a time. Some rear brake components are
different for left and right-hand sides, so don’t
mix them up.
Note 2:If the wheel cylinder is found to be
leaking or otherwise defective, renew it after
removing the brake shoes. This is simply a
matter of disconnecting the hydraulic line and
unbolting the cylinder from the backplate.
Attempting to overhaul a leaking cylinder is
unlikely to be satisfactory, even if spare parts
are available.
1Chock the front wheels, then loosen the
rear wheel bolts, raise the rear of the vehicle
and place it securely on axle stands. Remove
the rear wheels and release the handbrake.
2Remove the drum retaining screw (see
illustration)and remove the drum. If the drum
is stuck to the hub, spray the area between
the hub and the drum with penetrating oil
(see illustration). If the drum still won’t come
off, the shoes have probably worn ridges into
the drum, and will have to be retracted. Insert
a narrow flat-bladed screwdriver through one
of the holes in the hub flange (see
illustration)and back off the adjuster wheel
until the drum can be removed.
3Inspect the drum for cracks, score marks,
deep scratches and hard spots, which will
appear as small discoloured areas. If the hard
spots can’t be removed with emery cloth or if
any of the other conditions exist, the drum must
be taken to a specialist to have the drum
resurfaced. Note:Professionals recommendresurfacing the drums whenever a brake job is
done. Resurfacing will eliminate the possibility
of out-of-round drums. If the drums are worn so
much that they can’t be resurfaced without
exceeding the maximum allowable diameter
(which is cast into the drum) (see illustration),
then new ones will be required. At the very least,
if you elect not to have the drums resurfaced,
remove the glazing from the surface with emery
cloth or sandpaper, using a swirling motion.
Braking system 9•7
6.2b If the drum is stuck to the hub, apply
penetrating oil around the hub/drum area,
and give it a few minutes to loosen up
any rust6.2a Removing the drum retaining screw5.6d If a rear disc still sticks to the hub,
insert a thin, flat-bladed screwdriver
through the hub flange, rotate the
starwheel on the handbrake adjusting
screw, and contract the handbrake shoes
(disc removed for clarity)
6.3 The maximum allowable inside
diameter of the drum is cast into the drum
6.2c If the brake shoes have worn a
groove in the drum and it won’t come off,
insert a thin flat-bladed screwdriver
through one of the wheel bolt holes in the
flange, and loosen the automatic adjuster
mechanism (for the sake of clarity, the
drum has already been removed in this
photo, and the screwdriver is being
inserted underneath the flange instead of
though a wheel bolt hole)
9
If the front disc is stuck, on
some discs it is possible to
thread two or three bolts into
the holes provided and
tighten them. Alternate between the
bolts, turning them a couple of turns at
a time, until the disc is free.

Torque wrench settingsNm
Front suspension
Strut damper rod nut
Rod with external hexagon . . . . . . . . . . . . . . . . . . . . . . 65
Rod with internal hexagon . . . . . . . . . . . . . . . . . . . . . . 44
Strut cartridge threaded collar . . . . . . . . . . . . . . . . . . . . . . . 130
Strut upper mounting nuts . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Front control arm (3-Series)
Control arm-to-steering knuckle balljoint nut . . . . . . . . . . 64
Control arm-to-subframe balljoint nut . . . . . . . . . . . . . . . 83
Control arm bush bracket bolts . . . . . . . . . . . . . . . . . . . . 41
Lower control arm (5-Series)
Control arm-to-steering arm balljoint stud nut . . . . . . . . . 85
Control arm pivot bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Thrust arm (5-Series)
Thrust arm-to-steering arm balljoint stud nut . . . . . . . . . . 85
Thrust arm through-bolt . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Front hub (wheel bearing) nut . . . . . . . . . . . . . . . . . . . . . . . . 290
Steering arm-to-strut bolts (5-Series) . . . . . . . . . . . . . . . . . . 65
Anti-roll bar (3-Series)
Anti-roll bar-to-connecting link bolt . . . . . . . . . . . . . . . . . 41
Anti-roll bar mounting brackets-to-subframe . . . . . . . . . . 22
Connecting link-to-bracket . . . . . . . . . . . . . . . . . . . . . . . . 22
Connecting link bracket-to-control arm . . . . . . . . . . . . . . 41
Anti-roll bar (5-Series)
Anti-roll bar mounting brackets . . . . . . . . . . . . . . . . . . . . 22
Anti-roll bar link-to-strut housing locknut
Yellow chrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
White chrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Yellow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
10•2 Suspension and steering systems
Torque wrench settingsNm
Rear suspension
Rear shock absorber (3-Series)
Shock absorber-to-upper mounting bracket . . . . . . . . . . 12 to 15
Shock absorber-to-trailing arm . . . . . . . . . . . . . . . . . . . . 71 to 85
Rear shock absorber (5-Series)
Lower mounting bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 to 142
Upper mounting nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 24
Upper spring mounting-to-shock absorber locknut . . . . . 22 to 24
Trailing arms (3-Series)
Trailing arm-to-lower mounting . . . . . . . . . . . . . . . . . . . . 71 to 85
Trailing arm-to-anti-roll bar . . . . . . . . . . . . . . . . . . . . . . . . 22 to 23
Trailing arms (5-Series)
Trailing arm-to-rear axle carrier (rubber bush
through-bolt and nut) . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Trailing arm-to-axle carrier connecting link (1983-on) . . . 126
Rear wheel bearing drive flange axle nut (5-Series)
M22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 to 210
M27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235 to 260
Steering system
Steering wheel retaining nut . . . . . . . . . . . . . . . . . . . . . . . . . 79
Steering column universal joint pinch-bolt . . . . . . . . . . . . . . 22
Steering gear-to-subframe mounting bolts (3-Series) . . . . . 41
Steering box-to-front suspension subframe bolts (5-Series) 42
Track rod end-to-steering arm nut . . . . . . . . . . . . . . . . . . . . 37
Track rod end clamping bolt . . . . . . . . . . . . . . . . . . . . . . . . . 14
Pitman arm-to-steering box (5-Series) . . . . . . . . . . . . . . . . . 140
Steering linkage balljoints (all) . . . . . . . . . . . . . . . . . . . . . . . 37
1 General information
Warning: Whenever any of the
suspension or steering fasteners
are loosened or removed, they
must be inspected and if
necessary, new ones fitted, of the same
part number or of original-equipment
quality and design. Torque specifications
must be followed for proper reassembly
and component retention. Never attempt
to heat, straighten or weld any suspension
or steering component. Any bent or
damaged parts must be renewed.
The front suspension (see illustrations)is a
MacPherson strut design. The struts are
secured at the upper ends to reinforced areas
at the top of the wheel arches, and at the
lower ends to the steering arms/control arms.
An anti-roll bar is attached to the control arms
via connecting links, and to the suspension
subframe (3-Series models) or the underbody
(5-Series models).
The independent rear suspension system
on 3-Series models (see illustration)features
coil springs and telescopic shock absorbers.
The upper ends of the shock absorbers are
attached to the body; the lower ends are
connected to trailing arms. An anti-roll bar is
attached to the trailing arms via links, and to
the body with clamps.
The independent rear suspension system on
5-Series models (see illustration)uses coil-over shock absorber units instead of separate
shock absorbers and coil springs. The upper
ends are attached to the body; the lower ends
are connected to the trailing arms. The rear
suspension of 5-Series models is otherwise
similar to that of 3-Series models: two trailing
arms connected by an anti-roll bar.
The steering system consists of the
steering wheel, a steering column, a universal
joint shaft, the steering gear, the powersteering pump (where fitted) and the steering
linkage, which connects the steering gear to
the steering arms. On 3-Series models, a
rack-and-pinion steering gear is attached
directly to the steering arms via the track rods
and track rod ends. On 5-Series models, a
recirculating-ball steering box is connected to
the steering arms via a Pitman arm, a centre
track rod, the outer track rods and the track
rod ends.
1.1a Front suspension and steering components (3-Series models)
1 Subframe 3 Anti-roll bar link 5 Strut 7 Steering gear
2 Anti-roll bar 4 Control arm 6 Track rod end

6 Strut or shock absorber/coil
spring- renewal
4
Note:This section applies to all front strut
assemblies and, on 5-Series models, the rear
coil-over shock absorber assemblies.
1If the struts, shock absorbers or coil springs
exhibit the telltale signs of wear (leaking fluid,
loss of damping capability, chipped, sagging
or cracked coil springs) explore all options
before beginning any work. Strut or shock
absorber assemblies complete with springs
may be available on an exchange basis, which
eliminates much time and work. Whichever
route you choose to take, check on the cost
and availability of parts before dismantling the
vehicle.
Warning: Dismantling a strut or
coil-over shock absorber
assembly is a potentially
dangerous undertaking, and
utmost attention must be directed to the
job, or serious injury may result. Use only a
high-quality spring compressor, and
carefully follow the manufacturer’s
instructions supplied with the tool. After
removing the coil spring from the strut
assembly, set it aside in a safe, isolated
area.
2Remove the strut or shock absorber
assembly (see Section 5 or 11). Mount the
assembly in a vice. Line the vice jaws with
wood or rags to prevent damage to the unit,
and don’t tighten the vice excessively.
3Following the tool manufacturer’s
instructions, fit the spring compressor (these
can be obtained at most car accessory shops,
or it may be possible to hire one) on the
spring, and compress it sufficiently to relieve
all pressure from the suspension support (see
illustration). This can be verified by wiggling
the spring.
4Prise the protective cap off the damper rod
self-locking nut. Loosen the nut (see
illustration)with a spanner while holding thedamper rod stationary with another spanner
or an Allen key.
5Remove the nut, the strut bearing, the
insulator and the large washer. Check the
bearing for smooth operation. If it doesn’t turn
smoothly, renew it. Check the rubber insulator
for cracking and general deterioration. If there
is any separation of the rubber, renew the
insulator.
6Lift off the spring retainer and the rubber
ring at the top of the spring. Check the rubber
ring for cracking and hardness. Renew it if
necessary.
7Carefully lift the compressed spring from
the assembly and set it in a safe place, such
as a steel cabinet.
Warning: Never place your head
near the end of the spring!
8Slide the protective tube and rubber
bumper off the damper rod. If either is
damaged or worn, renew it.
9If you’re working on a front strut, loosen
and remove the threaded collar (see
illustration)and pull the old strut cartridge
from the strut housing. Pour the old oil from
the strut housing.
10On all struts except gas-charged units, fill
the strut housing with 20 to 25 cc (3-Series),
42 to 47 cc (518i and 520i 5-Series models) or
20 to 25 cc (all other 5-Series models) ofengine oil (the oil helps cool the shock
absorber by transferring heat to the strut
housing). Note:It doesn’t matter what
viscosity or grade of engine oil is used.
11Refitting is otherwise the reverse of
removal. Tighten the threaded collar to the
torque listed in this Chapter’s Specifications.
Make sure you align the end of the coil spring
with the shoulder of the rubber ring and with
the spring retainer (see illustration). Tighten
the damper rod nut to the torque listed in this
Chapter’s Specifications.
12Refit the strut or shock absorber
assembly (see Section 5 or 11).
7 Balljoints- check and renewal
3
Check
Note:On 3-Series models, there are two
balljoints on each control arm - one between
the middle of the arm and the subframe, and
the other between the outer end of the arm
and the steering knuckle. On 5-Series models,
there are balljoints on the outer ends of the
control arm and the thrust arm.
1Raise the vehicle and support it securely on
axle stands.
2Visually inspect the rubber boot between
the balljoint and the subframe or steering
knuckle, etc for cuts, tears or leaking grease.
If you note any of these conditions, renew the
control arm or thrust arm - the balljoints are
not available separately.
3Place a large lever under the balljoint, and
try to push the balljoint up. Next, position the
lever between the arm and the subframe or
between the arm and steering knuckle. If you
can see or feel any movement during either
check, a worn balljoint is indicated.
4Have an assistant grasp the tyre at the top
and bottom, and shake the top of the tyre with
an in-and-out motion. Touch the balljoint stud
nut. If any looseness is felt, suspect a worn
balljoint stud or a widened hole in the
subframe or steering knuckle. If the latter
Suspension and steering systems 10•7
6.4 Prise the protective cap off the
damper rod nut, and remove the large nut
(arrowed) - to prevent the damper rod from
turning, place an Allen key in the end of
the shaft6.3 Following the tool manufacturer’s
instructions, fit the spring compressor to
the spring, and compress it sufficiently to
relieve all pressure from the suspension
support
6.11 Make sure you align the end of the
coil spring with the shoulder of the rubber
ring, and with the spring retainer
6.9 Loosen and remove the threaded
collar, and pull the old strut cartridge from
the strut housing - on all struts except
gas-charged units, pour the old oil from
the strut housing. (Spring should have
been removed first!)
10

3 Interior trim- maintenance
1
Interior trim panels can be kept clean by
wiping with a damp cloth. If they do become
stained (which can be more apparent on light-
coloured trim), use a little liquid detergent and
a soft nail brush to scour the grime out of the
grain of the material. Do not forget to keep the
headlining clean in the same way. After
cleaning, application of a high-quality rubber
and vinyl protector will help prevent oxidation
and cracks. The protector can also be applied
to weatherstrips, vacuum lines and rubber
hoses, which often fail as a result of chemical
degradation, and to the tyres.
4 Upholstery and carpets-
maintenance
1
Mats and carpets should be brushed or
vacuum-cleaned regularly, to keep them free
of grit. If they are badly stained, remove them
from the vehicle for scrubbing or sponging,
and make quite sure they are dry before
refitting. Seats and interior trim panels can be
kept clean by wiping with a damp cloth. If they
do become stained (which can be more
apparent on light-coloured upholstery), use a
little liquid detergent and a soft nail brush to
scour the grime out of the grain of the
material. Do not forget to keep the headlining
clean in the same way as the upholstery.
When using liquid cleaners inside the vehicle,
do not over-wet the surfaces being cleaned.
Excessive damp could get into the seams and
padded interior, causing stains, offensive
odours or even rot.
5 Bodywork repair-
minor damage
3
Note:For more detailed information about
bodywork repair, Haynes Publishing produce
a book by Lindsay Porter called “The Car
Bodywork Repair Manual”. This incorporates
information on such aspects as rust treatment,
painting and glass-fibre repairs, as well as
details on more ambitious repairs involving
welding and panel beating.
Repairs of minor scratches in
bodywork
If the scratch is very superficial, and does
not penetrate to the metal of the bodywork,
repair is very simple. Lightly rub the area of
the scratch with a paintwork renovator, or a
very fine cutting paste, to remove loose paint
from the scratch, and to clear the surrounding
bodywork of wax polish. Rinse the area with
clean water.
Apply touch-up paint to the scratch using a
fine paint brush; continue to apply fine layers
of paint until the surface of the paint in the
scratch is level with the surrounding
paintwork. Allow the new paint at least two
weeks to harden, then blend it into the
surrounding paintwork by rubbing the scratch
area with a paintwork renovator or a very fine
cutting paste. Finally, apply wax polish.
Where the scratch has penetrated right
through to the metal of the bodywork, causing
the metal to rust, a different repair technique
is required. Remove any loose rust from the
bottom of the scratch with a penknife, then
apply rust-inhibiting paint to prevent the
formation of rust in the future. Using a rubber
or nylon applicator, fill the scratch with
bodystopper paste. If required, this paste can
be mixed with cellulose thinners to provide a
very thin paste which is ideal for filling narrow
scratches. Before the stopper-paste in the
scratch hardens, wrap a piece of smooth
cotton rag around the top of a finger. Dip the
finger in cellulose thinners, and quickly sweep
it across the surface of the stopper-paste in
the scratch; this will ensure that the surface of
the stopper-paste is slightly hollowed. The
scratch can now be painted over as described
earlier in this Section.
Repairs of dents in bodywork
When deep denting of the vehicle’s
bodywork has taken place, the first task is to
pull the dent out, until the affected bodywork
almost attains its original shape. There is little
point in trying to restore the original shape
completely, as the metal in the damaged area
will have stretched on impact, and cannot be
reshaped fully to its original contour. It is
better to bring the level of the dent up to a
point which is about 3 mm below the level of
the surrounding bodywork. In cases where the
dent is very shallow anyway, it is not worth
trying to pull it out at all. If the underside of the
dent is accessible, it can be hammered out
gently from behind, using a mallet with a
wooden or plastic head. Whilst doing this,
hold a suitable block of wood firmly against
the outside of the panel, to absorb the impact
from the hammer blows and thus prevent a
large area of the bodywork from being
“belled-out”.
Should the dent be in a section of the
bodywork which has a double skin, or some
other factor making it inaccessible from
behind, a different technique is called for. Drill
several small holes through the metal insidethe area - particularly in the deeper section.
Then screw long self-tapping screws into the
holes, just sufficiently for them to gain a good
purchase in the metal. Now the dent can be
pulled out by pulling on the protruding heads
of the screws with a pair of pliers.
The next stage of the repair is the removal
of the paint from the damaged area, and from
an inch or so of the surrounding “sound”
bodywork. This is accomplished most easily
by using a wire brush or abrasive pad on a
power drill, although it can be done just as
effectively by hand, using sheets of abrasive
paper. To complete the preparation for filling,
score the surface of the bare metal with a
screwdriver or the tang of a file, or
alternatively, drill small holes in the affected
area. This will provide a really good “key” for
the filler paste.
To complete the repair, see the Section on
filling and respraying.
Repairs of rust holes or gashes
in bodywork
Remove all paint from the affected area,
and from an inch or so of the surrounding
“sound” bodywork, using an abrasive pad or a
wire brush on a power drill. If these are not
available, a few sheets of abrasive paper will
do the job most effectively. With the paint
removed, you will be able to judge the severity
of the corrosion, and therefore decide
whether to renew the whole panel (if this is
possible) or to repair the affected area. New
body panels are not as expensive as most
people think, and it is often quicker and more
satisfactory to fit a new panel than to attempt
to repair large areas of corrosion.
Remove all fittings from the affected area,
except those which will act as a guide to the
original shape of the damaged bodywork (eg
headlight shells etc). Then, using tin snips or a
hacksaw blade, remove all loose metal and
any other metal badly affected by corrosion.
Hammer the edges of the hole inwards, in
order to create a slight depression for the filler
paste.
Wire-brush the affected area to remove the
powdery rust from the
surface of the remaining metal. Paint the
affected area with rust-inhibiting paint, if the
back of the rusted area is accessible, treat
this also.
Before filling can take place, it will be
necessary to block the hole in some way. This
can be achieved by the use of aluminium or
plastic mesh, or aluminium tape.
Aluminium or plastic mesh, or glass-fibre
matting, is probably the best material to use
for a large hole. Cut a piece to the
approximate size and shape of the hole to be
filled, then position it in the hole so that its
edges are below the level of the surrounding
bodywork. It can be retained in position by
several blobs of filler paste around its
periphery.
Aluminium tape should be used for small or
very narrow holes. Pull a piece off the roll, trim
11•2 Bodywork and fittings
If the inside of the vehicle
gets wet accidentally, it is
worthwhile taking some
trouble to dry it out properly,
particularly where carpets are involved.
Do not leave oil or electric heaters
inside the vehicle for this purpose.

it to the approximate size and shape required,
then pull off the backing paper (if used) and
stick the tape over the hole; it can be
overlapped if the thickness of one piece is
insufficient. Burnish down the edges of the
tape with the handle of a screwdriver or
similar, to ensure that the tape is securely
attached to the metal underneath.
Bodywork repairs - filling and
respraying
Before using this Section, see the Sections
on dent, deep scratch, rust holes and gash
repairs.
Many types of bodyfiller are available, but
generally speaking, those proprietary kits
which contain a tin of filler paste and a tube of
resin hardener are best for this type of repair. A
wide, flexible plastic or nylon applicator will be
found invaluable for imparting a smooth and
well-contoured finish to the surface of the filler.
Mix up a little filler on a clean piece of card
or board - measure the hardener carefully
(follow the maker’s instructions on the pack),
otherwise the filler will set too rapidly or too
slowly. Using the applicator, apply the filler
paste to the prepared area; draw the
applicator across the surface of the filler to
achieve the correct contour and to level the
surface. As soon as a contour that
approximates to the correct one is achieved,
stop working the paste - if you carry on too
long, the paste will become sticky and begin
to “pick-up” on the applicator. Continue to
add thin layers of filler paste at 20-minute
intervals, until the level of the filler is just
proud of the surrounding bodywork.
Once the filler has hardened, the excess
can be removed using a metal plane or file.
From then on, progressively-finer grades of
abrasive paper should be used, starting with a
40-grade production paper, and finishing with
a 400-grade wet-and-dry paper. Always wrap
the abrasive paper around a flat rubber, cork,
or wooden block - otherwise the surface of
the filler will not be completely flat. During the
smoothing of the filler surface, the wet-and-
dry paper should be periodically rinsed in
water. This will ensure that a very smooth
finish is imparted to the filler at the final stage.
At this stage, the “dent” should be
surrounded by a ring of bare metal, which in
turn should be encircled by the finely
“feathered” edge of the good paintwork.
Rinse the repair area with clean water, until all
of the dust produced by the rubbing-down
operation has gone.
Spray the whole area with a light coat of
primer - this will show up any imperfections in
the surface of the filler. Repair these
imperfections with fresh filler paste or
bodystopper, and once more smooth the
surface with abrasive paper. Repeat this
spray-and-repair procedure until you are
satisfied that the surface of the filler, and the
feathered edge of the paintwork, are perfect.
Clean the repair area with clean water, and
allow to dry fully.The repair area is now ready for final
spraying. Paint spraying must be carried out
in a warm, dry, windless and dust-free
atmosphere. This condition can be created
artificially if you have access to a large indoor
working area, but if you are forced to work in
the open, you will have to pick your day very
carefully. If you are working indoors, dousing
the floor in the work area with water will help
to settle the dust which would otherwise be in
the atmosphere. If the repair area is confined
to one body panel, mask off the surrounding
panels; this will help to minimise the effects of
a slight mis-match in paint colours. Bodywork
fittings (eg chrome strips, door handles etc)
will also need to be masked off. Use genuine
masking tape, and several thicknesses of
newspaper, for the masking operations.
Before commencing to spray, agitate the
aerosol can thoroughly, then spray a test area
(an old tin, or similar) until the technique is
mastered. Cover the repair area with a thick
coat of primer; the thickness should be built
up using several thin layers of paint, rather
than one thick one. Using 400-grade wet-and-
dry paper, rub down the surface of the primer
until it is really smooth. While doing this, the
work area should be thoroughly doused with
water, and the wet-and-dry paper periodically
rinsed in water. Allow to dry before spraying
on more paint.
Spray on the top coat, again building up the
thickness by using several thin layers of paint.
Start spraying at one edge of the repair area,
and then, using a side-to-side motion, work
until the whole repair area and about 2 inches
of the surrounding original paintwork is
covered. Remove all masking material 10 to
15 minutes after spraying on the final coat of
paint.
Allow the new paint at least two weeks to
harden, then, using a paintwork renovator, or
a very fine cutting paste, blend the edges of
the paint into the existing paintwork. Finally,
apply wax polish.
Plastic components
With the use of more and more plastic body
components by the vehicle manufacturers (eg
bumpers. spoilers, and in some cases major
body panels), rectification of more serious
damage to such items has become a matter
of either entrusting repair work to a specialist
in this field, or renewing complete
components. Repair of such damage by the
DIY owner is not really feasible, owing to the
cost of the equipment and materials required
for effecting such repairs. The basic technique
involves making a groove along the line of the
crack in the plastic, using a rotary burr in a
power drill. The damaged part is then weldedback together, using a hot-air gun to heat up
and fuse a plastic filler rod into the groove.
Any excess plastic is then removed, and the
area rubbed down to a smooth finish. It is
important that a filler rod of the correct plastic
is used, as body components can be made of
a variety of different types (eg polycarbonate,
ABS, polypropylene).
Damage of a less serious nature (abrasions,
minor cracks etc) can be repaired by the DIY
owner using a two-part epoxy filler repair
material. Once mixed in equal proportions,
this is used in similar fashion to the bodywork
filler used on metal panels. The filler is usually
cured in twenty to thirty minutes, ready for
sanding and painting.
If the owner is renewing a complete
component himself, or if he has repaired it
with epoxy filler, he will be left with the
problem of finding a suitable paint for finishing
which is compatible with the type of plastic
used. At one time, the use of a universal paint
was not possible, owing to the complex range
of plastics encountered in body component
applications. Standard paints, generally
speaking, will not bond to plastic or rubber
satisfactorily. However, it is now possible to
obtain a plastic body parts finishing kit which
consists of a pre-primer treatment, a primer
and coloured top coat. Full instructions are
normally supplied with a kit, but basically, the
method of use is to first apply the pre-primer
to the component concerned, and allow it to
dry for up to 30 minutes. Then the primer is
applied, and left to dry for about an hour
before finally applying the special-coloured
top coat. The result is a correctly-coloured
component, where the paint will flex with the
plastic or rubber, a property that standard
paint does not normally possess.
6 Bodywork repair-
major damage
5
1Major damage must be repaired by a
qualified bodywork repair specialist, or
preferably by a BMW dealer. Specialised
equipment is required to do the job properly.
2If the damage is extensive, the bodyshell
must be checked for proper alignment, or the
vehicle’s handling characteristics may be
adversely affected and other components
may wear at an accelerated rate.
3Due to the fact that all of the major body
components (bonnet, wings, etc.) are
separate units, any seriously damaged
components should be replaced with new
ones rather than repaired.
Bodywork and fittings 11•3
11
If bodystopper is used, it can
be mixed with cellulose
thinners to form a really thin
paste which is ideal for filling
small holes
Sometimes bodywork
components can be found in
a scrapyard that specialises
in used vehicle components,
often at a considerable saving over the
cost of new parts.

19 Steering column shrouds -
removal and refitting
1
Caution: If the radio in your
vehicle is equipped with an anti-
theft system, make sure you have
the correct activation code
before disconnecting the battery, Refer to
the information on page 0-7 at the front of
this manual before detaching the cable.
Note: If, after connecting the battery, the
wrong language appears on the instrument
panel display, refer to page 0-7 for the
language resetting procedure.
Removal
1Disconnect the battery negative cable.
2Remove the steering wheel (Chapter 10).
3Remove the upper shroud screws (see
illustration).
4Remove the two screws from the underside
of the column (see illustration).
5Detach the lower shroud, then lift the upper
half off the column (see illustrations).
Refitting
6Refitting is the reverse of removal.
20 Seats- removal and refitting
1
Front seat
1Remove the four bolts securing the seat
track to the floorpan, and lift the seat from the
vehicle (see illustration). On some models, it
will be necessary to disconnect the seat
heating wiring; it may also be necessary to
detach the seat belt from the seat.2Refitting is the reverse of removal. Tighten
the retaining bolts securely.
Rear seat cushion
3If applicable, first remove the two retaining
bolts. Grasp the front of the cushion
(Saloon/Convertible models) or the rear of the
cushion (Touring/Estate models) securely, and
pull up sharply (see illustration).
4Refitting is the reverse of the removal.
21 Seat belt check
1
1Check the seat belts, buckles, lock plates
and guide loops for obvious damage and
signs of wear.
2Where applicable, check that the seat belt
reminder light comes on when the ignition key
is turned to the Run or Start position.
3The seat belts are designed to lock up
during a sudden stop or impact, yet allow free
movement during normal driving. Check thatthe retractors return the belt against your
chest while driving and rewind the belt fully
when the buckle is unlocked.
4If any of the above checks reveal problems
with the seat belt system, renew parts as
necessary.
5Belts which have been subject to impact
loads must be renewed.
Bodywork and fittings 11•9
19.5a Pull the tilt lever down (where fitted),
and lower the shroud from the steering
column19.4 The lower screws are located under
the tilt lever (where fitted)19.3 Use a Phillips screwdriver to remove
the upper column shroud screws
20.3 Grasp the seat at the front edge and
pull up sharply (Saloon/Convertible
models)20.1 The front seats are held in place by
bolts (arrowed)
19.5b Rotate the upper shroud up and off
the steering column
11

12
Chapter 12 Body electrical systems
Bulb renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Central locking system - description and check . . . . . . . . . . . . . . . . 20
Cruise control system - description and check . . . . . . . . . . . . . . . . 19
Direction indicator/hazard warning flasher - check and renewal . . . 5
Electric windows - description and check . . . . . . . . . . . . . . . . . . . . 21
Electrical system fault finding - general information . . . . . . . . . . . . . 2
Fuses - general information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Headlight housing - removal and refitting . . . . . . . . . . . . . . . . . . . . . 14
Headlights - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Headlights - bulb renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Heated rear window - check and repair . . . . . . . . . . . . . . . . . . . . . . 17
Ignition switch - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 7
Instrument cluster - removal and refitting . . . . . . . . . . . . . . . . . . . . . 10
Radio - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Radio aerial - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Relays - general information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Service Indicator (SI) board - general information . . . . . . . . . . . . . . 11
Steering column switches - removal and refitting . . . . . . . . . . . . . . . 6
Supplemental Restraint System (SRS) - general information . . . . . . 18
Windscreen/tailgate wiper motor - removal and refitting . . . . . . . . . 16
Wiring diagrams - general information . . . . . . . . . . . . . . . . . . . . . . . 22
12•1
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert
DIY or professional
Degrees of difficulty Contents
1 General information
The chassis electrical system of this vehicle
is of 12-volt, negative earth type. Power for
the lights and all electrical accessories is
supplied by a lead/acid-type battery, which is
charged by the alternator.
This Chapter covers repair and service
procedures for various chassis (non-engine
related) electrical components. For
information regarding the engine electrical
system components (battery, alternator,
distributor and starter motor), see Chapter 5.
Warning: To prevent electrical
short-circuits, fires and injury,
always disconnect the battery
negative terminal before
checking, repairing or renewing electrical
components.
Caution: If the radio in your
vehicle is equipped with an anti-
theft system, make sure you have
the correct activation code
before disconnecting the battery, Refer to
the information on page 0-7 at the front of
this manual before detaching the cable.
Note: If, after connecting the battery, the
wrong language appears on the instrument
panel display, refer to page 0-7 for the
language resetting procedure.
2 Electrical system fault
finding- general information
2
A typical electrical circuit consists of an
electrical component, any switches, relays,
motors, fuses, fusible links or circuit breakers,
etc related to that component, and the wiring
and connectors that link the components to
both the battery and the chassis. To help you
pinpoint an electrical circuit problem, wiring
diagrams are included at the end of this book.
Before tackling any troublesome electrical
circuit, first study the appropriate wiring
diagrams to get a complete understanding of
what makes up that individual circuit.
Troublespots, for instance, can often be
isolated by noting if other components related
to that circuit are routed through the same
fuse and earth connections.
Electrical problems usually stem from
simple causes such as loose or corroded
connectors, a blown fuse, a melted fusible
link, or a bad relay. Inspect all fuses, wires
and connectors in a problem circuit first.
The basic tools needed include a circuit
tester, a high-impedance digital voltmeter, a
continuity tester and a jumper wire with an in-
line circuit breaker for bypassing electrical
components. Before attempting to locate or
define a problem with electrical testinstruments, use the wiring diagrams to
decide where to make the necessary
connections.
Voltage checks
Perform a voltage check first when a circuit
is not functioning properly. Connect one lead
of a circuit tester to either the negative battery
terminal or a known good earth.
Connect the other lead to a connector in
the circuit being tested, preferably nearest to
the battery or fuse. If the bulb of the tester
lights up, voltage is present, which means that
the part of the circuit between the connector
and the battery is problem-free. Continue
checking the rest of the circuit in the same
fashion.
When you reach a point at which no voltage
is present, the problem lies between that point
and the last test point with voltage. Most of
the time, problems can be traced to a loose
connection.Note:Keep in mind that some
circuits receive voltage only when the ignition
key is turned to a certain position.
Electrical fault diagnosis is simple if you
keep in mind that all electrical circuits are
basically electricity running from the battery,
through the wires, switches, relays, fuses and
fusible links to each electrical component
(light bulb, motor, etc) and then to earth, from
where it is passed back to the battery. Any
electrical problem is an interruption in the flow
of electricity to and from the battery.