1991 BMW 5 SERIES service indicator

indicates that the direction indicator and/or
hazard fuse has blown, check the wiring for a
short-circuit before fitting a new fuse.
4Make sure that the new unit is identical to
the original. Compare the old one to the new
one before fitting it.
5Refitting is the reverse of removal.
6 Steering column switches-
removal and refitting
1
Warning: Some later models are
equipped with an airbag or
Supplemental Restraint System
(SRS). To avoid possible damage
to this system, the manufacturer
recommends that, on airbag-equipped
models, the following procedure should be
left to a dealer service department, or
other specialist, because of the special
tools and techniques required. There is a
risk of injury if the airbag is accidentally
triggered.
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.
1Disconnect the battery negative cable,
remove the steering wheel (see Chapter 10)
and steering column shrouds (see Chapter 11).
Direction indicator/headlight
switch
2Where necessary, remove the switch
mounting screws. Depress the tabs and pull
the switch out of the steering column
mounting (see illustration).
3Trace the switch wires down the steering
column to the electrical connector, and
unplug them (see illustration).
4Refitting is the reverse of removal.
Wiper/washer switch
5Where necessary, remove the switch
mounting screws.
6Depress the release clip, and detach the
switch from the steering column mounting
(see illustration). Trace the switch wiring
down the steering column to the electrical
connector, and unplug it.
7Refitting is the reverse of removal.
Cruise control switch
8Remove the wiper/washer switch.
9Where necessary, remove the switch
mounting screw. Squeeze the release tabs,
and withdraw the switch from the mounting
(see illustration).
10Disconnect the switch electrical
connector from the harness at the base of the
steering column.
11Refitting is the reverse of removal.
7 Ignition switch-
removal and refitting
1
Warning: Some later models are
equipped with an airbag or
Supplemental Restraint System
(SRS). To avoid possible damage
to this system, the manufacturer
recommends that, on airbag-equipped
models, the following procedure should be
left to a dealer service department, or
other specialist, because of the specialtools and techniques required. There is a
risk of injury if the airbag is accidentally
triggered.
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 (see Chap-
ter 10).
3Remove the steering column shrouds (see
Chapter 11).
4Where necessary, remove the direction
indicator/headlight control switch (see Sec-
tion 6).
5Detach the clips by inserting a small
screwdriver into the openings on the sides
while pulling out on the switch (see
illustration).
6Unplug the electrical connector from the
harness at the base of the steering column,
and remove the switch.
Refitting
7Refitting is the reverse of removal.
Body electrical systems 12•3
6.3 Follow the wiring down the steering
column to the connector6.2 Squeeze the tabs to release the switch
from the mounting
6.9 Cruise control switch removal6.6 Squeeze the wiper/washer switch tabs
and pull it directly out of the mounting
12
5.1 The direction indicator/hazard warning
flasher unit is located on the steering
column on most models - squeeze the
tabs to detach it

8 Radio- 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.
2The radios on most models are held in place
by internal clips which are usually located at
the sides or corners of the unit faceplate.
Removal requires a special tool which is
inserted into the holes to release the clips so
the radio can be pulled out. These tools can be
fabricated from heavy wire, or are available
from your dealer or a car audio specialist. On
anti-theft radios, the clips are moved in and
out by internal screws which require another
type of tool. Insert the tool into the holes until
the clips release, then withdraw the radio from
the dash panel. Disconnect the wiring from the
radio and remove it.3On some models, the radio is held in place
by screws located beneath the faceplate. The
control knobs must be pulled off before the
faceplate can be withdrawn.
Refitting
4Refitting is the reverse of removal.
9 Aerial- 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.
2Use circlip pliers to unscrew the aerial
mounting nut.
3Open the boot lid/tailgate and remove the
left side trim panel. On some models, the jack
and tail light cluster cover will have to be
removed first.
4Unplug the aerial power and radio lead
connectors (as applicable), remove the
retaining bolts, and remove the aerial and
motor assembly.
Refitting
5Refitting is the reverse of removal.
10 Instrument cluster-
removal and refitting
2
Caution: The instrument cluster
and components are very
susceptible to damage from
static electricity. Make sure you
are earthed and have dischargedany static electricity (by touching an object
such as a metal water pipe) before
touching the cluster or 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.
Removal
1Disconnect the battery negative cable.
2As necessary, remove the steering column
shrouds and lower trim panel (see Chap-
ter 11).
3Remove the screws holding the cluster to
the facia (see illustration). Note the location
of the lower screws to ensure they are refitted
in the same place. On 3-Series models, the
length of the two lower inner screws must not
exceed 9.5 mm.
4Tilt the top of the cluster back, reach
behind it and detach the electrical connectors
by pressing on the levers, then lift the cluster
out of the facia opening (see illustration).
5For access to the cluster components,
release the catches or remove the screws,
and separate the two halves (see
illustration).
Refitting
6Refitting is the reverse of removal.
11 Service Indicator (SI) board-
general information
All models that have service indicator lights
are equipped with a Service Indicator (SI)
board located in the instrument cluster. This
board turns the lights on at the proper mileage
intervals. The lights can only be turned off
using a special tool which plugs into the
engine check connector (see Chapter 1). The
12•4 Body electrical systems
10.5 Turn the plastic knobs to release the
back of the cluster (some models use
screws)10.4 Push on the levers to detach the
cluster electrical connectors10.3 Use a Phillips screwdriver to remove
the instrument cluster retaining screws
7.5 Insert a screwdriver into the openings
(arrowed) on each side of the switch to
release the clip while pulling out

SI board is a self-contained computer which
includes a chip and batteries.
The rechargeable SI board nickel cadmium
(nicad) batteries maintain power to the
computer memory in the event of a power
drop (such as during starting) or complete
power loss (such as a dead or disconnected
battery) (see illustration). This assures power
so the computer can continue to keep track of
mileage and turn the lights on at the proper
interval.
The batteries have a life of approximately
six years, at which time they must be replaced
with new ones. Also, since they are recharged
by the engine charging system, they can run
down prematurely if power is cut off for some
reason (such as a blown fuse, a fault in the
wiring, or extended storage of the vehicle).
Excessive heat or cold can also shorten
battery life, with heat the greatest enemy.
Extreme heat can cause the batteries to
actually split open, allowing acid to drip into
the instrument cluster.
Several instruments controlled by the SI
board can be affected by low or discharged
batteries. Symptoms of low or dead SI board
batteries can include inconsistent tachometer
and temperature gauge readings, background
radio noise, and the inability to turn the
service lights off with the special tool.
Although only complete SI boards are
available from the manufacturer, batteries are
available separately from aftermarket sources.
While it is possible for the home mechanic to
renew the batteries, they are soldered to the
board, so unless you are skilled at this and
have the proper tools, this job should be left
to an experienced electronics technician.
Considerable savings can be realised by
removing the instrument cluster (see
Section 10) and taking it to an electronics
specialist.
Caution: the instrument cluster
and components are very
susceptible to damage from
static electricity. Make sure you
are earthed and have discharged any
static electricity (by touching an object
such as a metal water pipe) before
touching the cluster components.12 Headlights- bulb renewal
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.
1Disconnect the battery negative cable.
Sealed-beam type
2Remove the grille (see Chapter 11).
3Remove the headlight retainer screws,
taking care not to disturb the adjustment
screws.
4Remove the retainer and pull the headlight
out enough to allow the connector to be
unplugged.
5Remove the headlight.
6To refit the headlight, plug the connector in,
place the headlight in position, and refit the
retainer and screws. Tighten the screws
securely.7Refit the grille. Connect the battery negative
cable.
Halogen bulb type
Warning: Halogen gas-filled bulbs
are under pressure, and may
shatter if the surface is scratched
or the bulb is dropped. Wear eye
protection, and handle the bulbs carefully,
grasping only the base whenever possible.
Do not touch the surface of the bulb with
your fingers, because the oil from your
skin could cause it to overheat and fail
prematurely.
8From behind the headlight assembly,
remove the outer cover (see illustration).
9Twist and release the inner cover from the
rear of the headlight (see illustration).
10Disconnect the wire from the rear of the
headlight bulb (see illustration).
11Release the clips, and withdraw the bulb
from the headlight unit (see illustration).
12Fit the new bulb using a reversal of the
removal procedure. Make sure that the clips
engage the bulb correctly.
13Connect the battery negative cable.
Body electrical systems 12•5
12.9 Twist and release the headlight inner
cover12.8 Removing the headlight rear outer
cover (3-Series shown)11.2 These batteries (arrowed) power the
Service Indicator (SI) board
12.11 Removing the headlight bulb (do not
touch the surface of the bulb with your
fingers)12.10 Disconnecting the wire from the rear
of the headlight bulb
12
If you do touch the headlamp
bulb surface, clean it with
methylated spirit.

REF•13
REF
Fault Finding
Automatic transmission
Note:Due to the complexity of the automatic transmission, it is
difficult for the home mechanic to properly diagnose and service this
unit. For problems other than the following, the vehicle should be
taken to a dealer or transmission specialist.
Fluid leakage
m mAutomatic transmission fluid is a deep red colour. Fluid leaks
should not be confused with engine oil, which can easily be blown
by airflow onto the transmission.
m mTo pinpoint a leak, first remove all built-up dirt and grime from the
transmission housing with degreasing agents and/or by steam-
cleaning. Then drive the vehicle at low speed, so airflow will not
blow the leak far from its source. Raise the vehicle and determine
where the leak is coming from. Common areas of leakage are:
a) Transmission sump (Chapters 1 and 7B)
b) Filler pipe (Chapter 7B)
c) Transmission fluid cooler lines (Chapter 7B)
d) Speedometer sensor (Chapter 7B)
Transmission fluid brown, or has a burned smell
m mTransmission fluid burned; fluid should be changed. May indicate
transmission internal fault (Chapters 1 and 7B).
Transmission will not kickdown with accelerator
pedal pressed to the floor
m mKickdown cable out of adjustment (Chapter 7B).
General shift mechanism problems
m
mChapter 7B deals with checking and adjusting the shift linkage on
automatic transmissions. Common problems which may be
attributed to poorly-adjusted linkage are:
a) Engine starting in gears other than Park or Neutral.
b) Indicator on selector lever pointing to a gear other than the one
actually being used.
c) Vehicle moves when in Park.
m mRefer to Chapter 7B for the shift linkage adjustment procedure.
Engine will start in gears other than Park or Neutral
m
mInhibitor switch malfunctioning (Chapter 7B).
Transmission slips, shifts roughly, is noisy, or has
no drive in forward or reverse gears
m mThere are many probable causes for the above problems, but the
home mechanic should be concerned with only one possibility -
fluid level. Before taking the vehicle to an automatic transmission
specialist, check the level and condition of the fluid as described in
Chapter 1. Correct the fluid level as necessary, or change the fluid
if needed. If the problem persists, have a professional diagnose the
probable cause.
Manual transmission
Vibration
m mDamaged propeller shaft (Chapter 8).
m mOut-of-round tyres (Chapter 1).
m mTyre out-of-balance (Chapters 1 and 10).
m mWorn propeller shaft universal joint (Chapter 8).
Noisy in neutral with engine running
m
mWorn clutch release bearing (Chapter 8).
m mWorn transmission input shaft bearing (Chapter 7A).
Noisy in one particular gear
m
mDamaged or worn constant-mesh gears.
m mDamaged or worn synchronisers.
Noisy in all gears
m
mInsufficient lubricant (Chapter 1).
m mDamaged or worn bearings.
m mWorn or damaged input gear shaft and/or output gear shaft.
Slips out of gear
m
mWorn or incorrectly-adjusted linkage (Chapter 7A).
m mTransmission-to-engine mounting bolts loose (Chapter 7A).
m mShift linkage binding (Chapter 7A).
m mWorn shift fork (Chapter 7A).
Leaks lubricant
m
mExcessive amount of lubricant in transmission (Chapters 1 and 7A).
m mLoose or broken input shaft bearing retainer (Chapter 7A).
m mInput shaft bearing retainer O-ring and/or lip seal damaged
(Chapter 7A).

REF•27
REF
Index
R
Radiator - 3•3, 11•4
Radio - 12•4
Receiver-drier - 3•9
Regulator (voltage) - 5•10
Regulator (window) - 11•8
Relays - 12•2
Repair procedures - REF•8
Respraying - 11•3
Reversing light switch - 7B•4
Rocker arms - 2B•11
Rotor - 1•18
Routine maintenance and servicing- 1•1
et seq
Routine maintenance - air conditioning
system - 3•8
Routine maintenance - bodywork and
underframe - 11•1
Routine maintenance - hinges and locks -
11•4
Routine maintenance - interior trim - 11•2
Routine maintenance - upholstery and
carpets - 11•2
Rust holes in bodywork - 11•2
S
Safety first! - 0•5
Scalding - 0•5
Scratches in bodywork - 11•2
Screw threads and fastenings - REF•8
Seat belt - 11•9, REF•2
Seats - 11•9, REF•2
Selector lever - 7B•3, 7B•5
Selector shaft - 7A•2
Service Indicator (SI) board - 12•4
Service indicator light - 1•26
Servo - 9•2, 9•10, 9•11
Shock absorber - 1•21, 10•7, 10•8, 10•9,
REF•2, REF•3
Shoes - 9•7
Short-circuit - 12•2Silencer - 4•20
Slave cylinder - 8•3
Spares - REF•19
Spark plug - 1•17, 1•18
Speed sensors - 5•8
Springs - 10•7, 10•9, REF•3
Starter inhibitor - 7B•4
Starter motor - 5•12
Starter motor fault - REF•10
Starting system - 5•11
Steering box - 10•15
Steering column - 11•9, 12•3, REF•1
Steering gear - 10•12, 10•13, REF•3
Steering linkage - 10•14
Steering wheel - 10•16, REF•1
Stop-light switch - 9•13
Struts - 1•21, 10•6, 10•7
Sump - 2A•15
Supplemental Restraint System (SRS) -
12•8
Suspension and steering systems- 1•21,
1•22, 10•1et seq, REF•2, REF•3
Suspension and steering fault finding -
REF•15
Switches - 7B•4, 9•13, 12•3
T
Tailgate - 11•6
Tappets - 2B•11
Thermostat - 3•2
Thermotime switch - 4•17, 4•18
Throttle body - 4•16
Throttle linkage - 1•20
Throttle Position Sensor (TPS) - 6•3
Throttle positioner - 4•13, 4•14
Thrust arm - 10•5
Timing - 5•4
Timing belt - 1•26, 2A•8, 2A•9
Timing chain - 2A•6, 2A•8
Timing sensors - 6•4
Tools - REF•5, REF•7, REF•8
Top Dead Centre (TDC) for No 1 piston -
2A•3Torque converter - 7B•5
Towing - 0•8
Track rod ends - 10•13
Trailing arms - 10•10
Transmission - SeeManual transmission or
Automatic transmission
Trim - 11•2, 11•6
Tyres - 1•9, 1•14, 10•16, REF•4, REF•15
U
Underframe - 11•1
Universal joints - 8•8
Upholstery - 11•2
V
Vacuum hoses - 1•14
Vacuum servo - 9•10
Valve clearances - 1•19
Valve cover - 2A•4
Valves - 2B•10, 2B•11
Vehicle identification - REF•2, REF•19
Voltage checks - 12•1
Voltage regulator - 5•10
W
Washer fluid - 1•9
Water pump - 3•5
Weekly checks- 1•7et seq
Wheel alignment - 10•17
Wheel bearings - 10•8, 10•11, REF•3
Wheel changing - 0•8
Wheels - 10•16, REF•4
Windows - 11•8, 12•9
Windscreen - REF•1
Wiper blades - 1•23
Wiper motor - 12•7
Wiring diagrams- 12•9et seq
Working faclities - REF•7