121-2
BATTERY,
STARTER,
ALTERNATOR
CHARGING
SYSTEM
TROUBLESHOOTING
Static
currentdraw,
checking
Charging
system
diagnostics
requires
special
test
equip-
ment
.
If
the
test
equipment
is
not
available,
charging
system
fault
diagnosis
can
be
performedby
an
authorized
BMW
deal-
eror
other
qualified
repair
shop
.
A
general
troubleshooting
guide
is
given
in
Table
a
.
Charging
System
Quick-Check
As
a
quick-check,
use
a
digital
multimeter
lo
measure
volt-
2
.
Disconnect
battery
negative
(-)
cable
.
age
across
the
battery
terminals
with
the
key
off
and
then
again
with
the
engine
running
.
The
battery
voltage
should
be
CAUTION-
about12
.6
volts
with
key
off
and
approximately
14
.0
volts
with
Prior
to
disconnecting
the
battery,
read
the
battery
the
engine
running
.
If
the
voltage
does
not
increase
when
the
disconnection
cautions
given
at
the
front
of
this
engine
is
running,there
is
a
fault
in
the
charging
system
.
manual
onpaga
viii
.
NOTE
-
The
regulated
voltage
(engine
running)
should
be
be-
tween
13
.5
and
14
.5,
depending
on
temperatura
and
operating
conditions
.
If
the
voltage
is
higher
than
14
.8,
the
voltage
regulator
is
most
Mely
faulty
.
Check
for
clean
and
tight
battery
cables
.
Check
the
ground
cable
running
from
the
negative
(-)
battery
terminal
lo
the
chassis
and
the
ground
cable
running
from
the
engine
lo
the
chassis
.
Check
the
alternator
drive
belt
condition
and
tension
.
If
the
battery
discharges
over
time,
there
may
be
a
constant
drain
or
current
draw
on
the
battery
.
A
small
static
drain
on
the
battery
is
normal,
but
a
largedrain
will
cause
the
battery
lo
quickly
discharge
.
Make
a
static
current
draw
test
asthe
first
step
when
experiencing
battery
discharge
.
1
.
Make
sure
ignition
and
al¡
electrical
accessories
are
switched
off
.
3
.
Connect
a
digital
ammeter
between
negative
battery
post
and
negative
battery
cable
lo
measure
current
.
See
Fig
.
1
.
Wait
at
least
one
minuta
lo
get
an
accurate
reading
.
A
range
of
about
0
lo
100
milliamps
is
normal,
dependingon
the
number
of
accessories
that
need
constant
power
.
A
current
of
400
milliamps
(0.4
amp)
or
more
may
indicate
a
problem
.
Table
a
.
Battery,
Starter
and
Charging
System
Troubleshooting
Symptom
1
Probable
Cause
1
Correctiva
Action
1
.
Engine
cranks
slowlyor
not
a
.
Battery
cables
loose,
dirty
orcor-
a
.
Clean
or
replace
cables
.
See020
Maintenance
Program
.
a
tall,
solenoíd
clicks
when
roded
.
starter
is
operated
.
b
.
Battery
discharged
.
b
.
Charge
battery,
test
and
replace
if
necessary
.
c
.
Body
ground
straploose,
dirty
or
c
.
Inspect
ground
strap,
clean,
tighten
or
replace
if
necessary
.
corroded
.
d
.
Poor
connection
at
starter
motor
d
.
Check
connections,
test
for
voltage
at
starter
.
Test
for
voltage
at
terminal
30
.
neutral
safety
or
clutch
interlock
switch
.
e
.
Starter
motor
or
solenoid
faulty
.
e
.
Test
starter
.
2
.
Battery
will
not
stay
a
.
Short
circuit
draining
the
battery
.
a
.
Test
for
excessive
current
drainwith
everything
electrical
in
the
charged
more
than
a
few
vehicle
off
.
days
.
b
.
Short
driving
trips
and
high
elec-
b
.
Evaluate
driving
style
.
Where
possible,
reduce
electrical
con
trical
drain
on
charging
system
sumption
when
making
short
trips
.
does
not
allow
battery
to
re-
charge
.
c
.
Drive
belt(s)
worn
or
damaged
.
c
.
Inspect
or
replace
multi-ribbed
belt(s)
.
See
020
Maintenance
Program
.
d
.
Battery
faulty
.
d
.
Test
battery
and
replace
íf
necessary
.
e
.
Battery
cables
loose,
dirty
orcor-
e
.
Clean
or
replace
cables
.
See
020
Maintenance
Program
.
rodad
.
f
.
Alternatoror
voltage
regulator
f
.
Test
alternator
and
voltage
regulator
.
faulty
.
3
.
Battery
losing
water
.
1
a
.
Battery
overcharging
.
1
a
.
Test
voltage
regulator
for
proper
operation
.
4
.
Lights
dim,
light
intensity
a
.
Drive
belt(s)
worn
or
damaged
.
a
.
Inspect
or
replace
multi-ribbed
belt(s)
.
See
020
Maintenance
varies
with
engine
speed
.
Program
.
b
.
Alternatoror
voltage
regulator
b
.
Test
alternator
and
voltage
regulator
.
faulty
.
c
.
Body
ground
straps
loose,
dirty
or
c
.
Inspect
ground
straps,
clean,
tighten
or
replace
as
necessary
.
corroded
.
CHARGING
SYSTEM
TROUBLESHOOTING
Alternator
brushes,
STARTER
SERVICE
inspecting
and
replacing
Regulator
brushesarenot
available
as
replacement
parts
from
BMW
.
Replacement
brushes
may
be
available
from
af-
termarket
sources,
however
.
1
.
Remove
voltage
regulator
as
described
above
.
2
.
Clean
brush
contact
sürfaces
and
measure
brush
pro-trusion
.
See
Fig
.
7
.
Check
for
battery
voltage
at
terminal
50
of
the
starter
motor
Fig
.
7
.
Regulator
brush
protrusion
(A)
.
with
the
key
in
the
start
position
.
See
Fig
.
8
.
If
voltage
is
not
present,
check
the
wiring
between
the
ignition
switch
and
the
starter
terminal
.
If
voltage
is
present
and
no
other
visible
wir
Voltage
Regulator
ing
faults
can
be
found,
the
problem
is
most
likely
interna¡in
"
Brush
protrusion
(minimum)
.......
.
..
5
mm
(
1
/4
in
.)
the
starter
motor
.
3
.
To
replace
brushes,
carefully
and
as
quickly
as
possi-
ble,
unsolder
brush
lead
from
brush
holder
termina¡,
withdrawing
brush
from
holder
at
same
time
.
4
.
Remove
any
traces
of
solder
frombrush
holder
termi-
nal
using
solder
wick
.
5
.
Fit
spring
into
brush
holder
and
inserí
new
brush
.
6
.
Guide
brush
lead
into
terminal
and
solder
into
place
.
Check
for
free
movement
of
brushes
when
solder
cools
.
7
.
Check
brush
slip
rings
in
alternator
for
wear
.
Lightly
clean
slip
rings
using
fine
abrasive
cloth
.
BATTERY,
STARTER,
ALTERNATOR
121-
7
Starter
Troubleshooting
If
the
starter
tucos
the
engine
slowlyor
fails
to
operate
when
the
ignition
isin
the
start
position,
check
the
battery
first
.
In-
spect
the
starter
wires,
terminals,
and
ground
connections
for
good
contact
.
In
particular,
make
sure
the
ground
connections
between
the
battery,
the
body
and
the
engine
are
completely
clean
and
tight
.
If
no
faults
can
be
found,
the
starter
may
be
faulty
and
should
be
replaced
.
NOTE
-
"
Starting
in1194,
a
factory-installed
drive-away
protec-
tion
system,
alsoreferred
to
as
EWS
or
EWS
11,
was
used
on
all
E36
cars
.
This
system
prevenís
operation
of
the
starter
when
the
system
is
engaged
.
See
515
Central
Locking
and
Anti-theft
.
"
On
cars
with
automatic
transmission,
a
starter
relay
and
a
neutral
safetyswitchare
used
to
present
theen-
ginefrom
starting
in
gear
positions
other
than
park
or
neutral
.
ff
voltage
is
not
present
atterminal
50
with
the
key
in
the
startposition,
check
these
components
To
make
the
most
accurate
check
of
the
battery
cables
and
starterwiring,
make
a
voltage
drop
test
on
the
cables
and
wir-
ing
as
described
in
600
Electrical
System-General
.
Terminal
30
'
\
/
Terminal
30h
0012518
8
.
Reinstall
regulator
and
alternator
.
Fig
.
8
.
Typical
starterwiring
terminal
identification
.
Large
wireat
ter-
minal
30
is
direct
battery
voltage
.
Smaller
wire
at
terminal
50
operates
starter
solenoid
via
ignition
switch
.
STARTER
SERVICE
Table
j.
ECM
Pin
Assignment-Bosch
DME
M3
.3
.1
Pin
~
Signal
1
Componentffunction
1
signal
FUEL
INJECTION
130-
33
45
ground
Ignition
circuit
shield
Ground
shieldfor
ignition
circuit
monitoring
46
output
Fuel
consumption
(KVA
signal)
To
instrument
cluster
47
output
Crankshaft
rpm
Engine
speed
(TD)
signal
to
instrument
cluster
48
output
A/C
compressor
control
A/C
compressor
relay
terminal
85
49
vacant
-
-
50
output
Ignition
coil
control,
cyl
.
1
Primary
signal,
ignition
coil
1
51
output
Ignition
coil
control,
cyl
.
2
Primary
signal,
ignition
coil
2
52
output
Ignition
coil
control,
cyl
.
3
Primary
signal,
ignition
coil
3
53
vacant
-
-
54
input
Power
supply
Battery
voltagefrom
main
relay
(terminal
87a)
55
ground
Ground
Ground
for
ignition
control
56
input
Power
supply
(terminal15)
Batteryvoltage
with
key
on
or
engine
running
57
input
Ignition
timing
intervention
From
A/T
control
module
58
vacant
-
-
59
output
Throttleposition
sensor
(TPS)
Voltage
supply
to
TPS
(5
VDC)
60
input
Programming
voltage
Data
link
connector
61
vacant
-
-
62
vacant
-
-
63
vacant
-
-
64
input
A/C
on
signal
From
integrated
climate
control
module
65
input
A/C
pressure
signal
From
integrated
climate
control
module
via
A/C
pressure
switch
66
input
On-board
computer
Drive-away
protection
enable
(starter
immobilization
relay)
67
vacant
-
-
68
vacant
-
-
69
input
Knock
sensor
#2
(cyl
.
4,5,
6)
Knock
sensor
#2
signal
70
input
Knock
sensor
#1
(cyl
.
1,2,
3)
Knock
sensor
#1
signal
71
ground
Ground
Ground
for
knock
sensors
and
shields
72
vacant
-
-
73
input
Throttleposition
sensor
(TPS)
Throttleposition
signal
74
vacant
-
75
vacant
-
-
76
vacant
-
77
input
Intakeair
temperatura
Intakeair
temperatura
sensor
(0-5
VDC)
78
input
Engine
coolant
temperature
Engine
coolant
temperature
sensor
(0-5
VDC)
79
vacant
-
80
vacant
-
-
81
input
Automatic
transmission
gear
positionlneutral
A/T
parkor
neutral
position
signal
safetyswitch
82
vacant
-
-
83
vacant
-
-
84
vacant
-
-
85
vacant
-
-
86
vacant
-
-
87
input
Diagnostic
connector
(RxD)
Diagnostic
RxD
(receive)
signal
to
pin
15
in
Data
link
connector
88
input/output
Diagnostic
connector
(TxD)
Diagnostic
TxD
(transmit)
signal
to
pin
20
in
Data
link
connector
ECM
PIN
ASSIGNMENTS
GENERAL
.
.
.
.
.
.
.
.
.
................
.
.
.
250-1
AUTOMATIC
TRANSMISSION
GEARSHIFT
...
.
.........
.
.
.
.
.
.
.
.
.
.
.
.
.
.
250-3
MANUAL
TRANSMISSION
Gearshift
mechanism,
adjusting
GEARSHIFT
.
.
.
.
.
.
.
.....
.
..........
.
.
.
250-1
(automatictransmission)
..
.
.
.
.
.
.
.
.
.
...
.
.
250-3
Gearshift
lever,
removing
Gear
position/neutral
safety
switch,
replacing
(manual
transmission)
.
.
.
.
...
.
.
.
.......
250-1
(automatic
transmission)
..
.
.
.
.........
.
.
250-4
Gearshift
lever,
installing
Automatic
shiftlock,
checking
function
(manual
transmission)
.
.
.
.
.
.
.
.
.
.
.......
250-2
(automatic
transmission)
..
..
...
.
.
.
....
..
250-5
Shiftinterlock,
checking
function
(automatic
transmission)
.......
.
.
.
.....
.250-6
GENERAL
This
repair
group
covers
transmission
gearshift
and
linkage
service
.
Special
service
tools
are
required
for
some
of
the
proce-
dures
given
here
.
To
gain
access
to
the
complete
gearshift
mechanism
ít
is
necessary
to
remove
the
exhaust
system
and
the
driveshaft
as
described
in
180
Exhaust
System
and260
Driveshaft
.
MANUAL
TRANSMISSION
GEARSHIFT
Gearshift
lever,
removing
(manual
transmission)
The
manual
transmission
gearshift
linkage
is
shown
in
Fig
.1
.
Use
thisillustration
asaguide
when
removing
and
installing
the
linkage
.
1
.
Pull
straight
upon
shift
knob
lo
remove
it
from
shift
lever
.
NOTE
-
Removal
of
the
shift
knob
will
require
about
90
lbs
.
of
force
.
2
.
Pry
upon
rear
of
shift
boot
tounclip,
then
remove
boot
from
front
retainers
.
3
.
Raise
vehicle
togain
access
to
underside
of
vehicle
.
WARNING
-
Make
sure
thecar
is
stable
and
well
supported
at
afl
times
.
Use
a
professional
automotive
lift
orjackstands
designed
for
the
purpose
.
A
floor
jack
is
not
adequate
support
.
250
Gearshift
Linkage
GEARSHIFT
LINKAGE
250-1
Fig
.1
.
Manual
transmission
gearshift
linkage
.
4
.
Disconnect
oxygen
sensorharness
connectors
.
Re-
move
completeexhaust
system
.
See
180
Exhaust
System
.
MANUAL
TRANSMISSION
GEARSHIFT
2
.
Install
rubber
grommet
with
arrow
pointing
forward
.
In-
AUTOMATic
TRANSMISSION
stall
shift
rod
and
shift
boot
.
GEARSHIFT
NOTE-
Install
rubbergrommet
correctly
so
that
is
seals
outwa-
ter
.
4
.
Install
driveshaft
and
heat
shield
.
See
260
Driveshaft
.
Manual
valveleven
(at
transmission)
Fig
.
6
.
Automatic
transmission
gearshift
assembfy
.
Shift
cable
GEARSHIFT
LINKAGE
250-
3
The
automatic
transmission
shift
mechanism
is
shown
in
Fig
.
6
.
Use
the
illustration
as
a
guide
when
servícing
the
gear-
shift
mechanism,
including
shift
cable
replacement
.
3
.
Connect
shift
rod
to
shift
lever
.
Install
transmission
crossmember
.
Lift
transmission
and
tighten
crossmem-
Gearshift
mechanism,
adjusting
ber
bolts
.
(automatictransmission)
NOTE-
1
.
Position
selector
lever
in
Park
.
Beforeconnecting
the
shift
rod
to
the
lever,
be
sure
the
2
.
Raise
vehicle
to
gain
access
to
shift
linkage
.
gearshift
leven
is
facing
the
correct
way
as
illustrated
in
Fig
.
1
.
WARNING
-
Make
sure
thecan
is
stable
and
well
supported
at
all
times
.
Use
a
professional
automotive
lift
or
jack
stands
designed
for
the
purpose
.
5
.
Reinstall
exhaust
system
.
See
180
Exhaust
System
.
Connect
oxygen
sensor
harness
connectors
.
3
.
Loosen
selector
cable
clamping
nut
.
See
Fig
.
7
.
6
.
Lower
vehicle
.
Insta¡¡
shift
boot
cover
.
Push
shift
knob
4
.
Push
shift
lever
forwardtoward
engine(Park
position)
onto
lever
.
while
applying
light
pressure
on
cable
end
.
Tighten
ca-
ble
clamping
nut
.
Tightening
Torques
NOTE-
"
Driveshaft
to
final
drive
Do
not
overtighten
the
nut
so
that
it
twists
the
cable
.
flange
(with
U-joint)
.
..
.
.....
.
.
See
250
Driveshaft
"
Flex-disc
to
driveshaft
or
transmission
flange
...
.
.......
See
250
Driveshaft
Tightening
Torque
"
Transmission
crossmember
"
Shift
cable
clamping
nut
.......
10-12
Nm
(75-9
ft-Ib)
to
body
(M8)
.
.
.
...
..............
21
Nm
(16
ft-Ib)
/S
r\
1
1
Gear
position/
neutral
safetyswitch
Automatic
shilo
solenoid
id
AUTOMATIC
TRANSMISSION
GEARSHIFT
250-
4
GEARSHIFT
LINKAGE
r%
;
5
(((((C
"
~
;
Fig
.
7
.
Selector
lever
cable
clamping
nut
(A)
.
Counterhold
clamping
bolt
when
loosening
nut
.
Gear
position/neutral
safety
switch,
replacing
(automatic
transmission)
NOTE-
The
gear-positionlneutral
safetyswitch
is
also
some-
times
referred
to
as
the
automatic
transmission
range
switch
.
Failure
of
the
gear
positionlneutral
safetyswitch
can
cause
a
no-start
condition
.
In
acidition,
since
it
signals
gearshift
posi-
tion
tothe
transmission
control
unit,
a
faulty
switch
can
cause
erratic
transmission
operation
.
1
.
Remove
hex-head
screw
(3mm
allen
key)
from
shift
le-
ver
handle
and
remove
handle
.
Carefully
pry
up
cover
from
gearshift
lever
console
.
2
.
Disconnect
harness
connector
from
gear
positionlneu-
tral
safety
switch
andremove
mounting
screws
.
See
Fig
.
8
.
3
.
Remove
gear
positionlneutral
safety
switch
by
moving
selector
until
pin
on
lever
aligns
with
slot
on
switch
.
Pull
switch
straight
up
and
off
.
See
Fig
.
9
.
4
.
Installation
is
reverse
of
removal,
noting
the
following
:
"
Before
installing
switch,
align
plastic
contact
slide
in-
sideswitch
with
slot
in
switch
.
See
Fig
.
10
.
"
Instan
switch
so
that
contact
slide
on
switch
aligns
with
slot
on
switch
.
Then
position
gearshift
lever
pin
to
slot
on
switch
and
install
switch
.
"
When
installing
shift
lever
handle,
engage
pín
on
re
leasebutton
to
hole
in
pulí
rod
.
See
Fig
.
11
.
Fig
.
9
.
Contact
slide
in
switch
aligns
toslot
on
switch
and
pin
on
le-
ver
.
Tightening
Torques
"
Console
to
body
..............
...
.
7
Nm
(62
in-lb)
"
Gear
positionlneutral
safety
switch
to
shift
console
.................
.
4
.5
Nm
(40
in-lb)
AUTOMATIC
TRANSMISSION
GEARSHIFT
Fig
.
8
.
Disconnect
harness
connector
to
gear
position/neutral
safety
switch
by
pressing
connector
retaining
clips
together
(ar-
rows)
.
Switch
mountingscrews
shown
at
1
.
Fig
.
10
.
Align
contact
slide
(1)
with
slot
in
switch
housing
(2)
before
in-
stalling
gear
position/neutral
safety
switch
.
Fig
.
11
.
Engage
release
button
pin
to
hole
in
pull
rod
before
installing
The
automatic
shiftlock
uses
an
electríc
solenoid
to
lock
the
selector
lever
in
P
or
N
.
Depressing
the
foot
brake
withthe
ig-
nition
on
energizes
the
solenoid,
allowingthe
lever
to
be
moved
into
a
drive
gear
.
The
solenoid
is
energized
only
when
the
engine
speed
is
below
2,500
rpmand
thevehicle
speed
is
below
3
mph
.
The
solenoid
ís
mounted
in
the
right-hand
side
of
theselector
lever
housing
.
See
Fig
.
12
.
1
.
With
engine
running
and
car
stopped,
place
selector
le-
ver
in
P
or
N
.
2
.
Without
depressing
brake
pedal,
check
that
selector
le-
ver
is
locked
in
position
P
or
N
.
3
.
Depress
brakepedal
firmly
.
Solenoid
should
be
heard
to
energize
.
GEARSHIFT
LINKAGE
250-
5
Fig
.
12
.
Automatic
shiftlock
prevents
drive
gear
selection
until
the
brakepedal
is
depressed
.
4
.
Check
thatselector
lever
can
now
be
moved
out
of
P
or
N
.
NOTE
-
The
next
test
should
be
performed
in
anopen
area
with
the
parking
brake
on
and
with
extreme
caution
.
5
.
With
selector
lever
in
P
or
N
and
brake
pedal
de-
pressed,
raise
engine
above
2,500
rpm
.
Check
that
se-
lector
lever
cannotbe
moved
outof
P
or
N
.
shift
lever
handle
.
If
any
faults
are
found
check
the
electrical
operation
of
the
shiftlock
solenoid
and
check
for
wiring
faultsto
or
from
the
Automatic
shiftiock,
checking
function
transmission
control
module(TCM)
.
See610
Electrical
(automatic
transmission)
Component
Locations
and
Electrical
Wiring
Diagrams
.
NOTE
-
The
solenoid
is
controlled
viathe
TCM,
using
brakepedal
position,
engine
speed,
and
road
speed
as
con-
trolling
inputs
.
AUTOMATIC
TRANSMISSION
GEARSHIFT
Fig
.
5
.
Splice
panel
under
left
side
of
dash
.
SplicePanel,
Right
ir1!
1,
111lí~lll
.
'
ELECTRICAL
COMPONENT
LOCATIONS
610-3
0013091
1
.
Unloader
relay
4
.
Starter
immobilization
2
.
Wiper
relay
relay
(1994
only)
3
.
Wiper
motor
relay
F47
&
F50
Fuses47
and
50
The
right
splice
panel
contains
three
relay
positions
.
It
is
lo-
cated
under
the
right
side
of
the
dashboard
.
To
access
the
panel,
remove
theglove
compartment
as
de-
scribed
in
513
Interior
Trim
.
See
Fig
.
6
.
Fig
.
6
.
Splice
panel
under
right
side
of
dash
(arrow)
.
Glove
compart-
ment
and
right
side
vents
shown
removed
.
COMPONENT
LOCATIONS
On
the
following
pages
are
illustrations
and
photos
showing
the
location
of
major
electrical
components
in
E36
vehicles
.
NOTE-
-
Every
component
is
not
installed
in
everycar
.
"
Due
to
changes
in
production,
component
locations
may
vary
from
what
is
illustrated
.
Consult
your
BMW
dealer
for
the
latest
information
.
"
The
gear-position/neutral
safety
switch
ís
also
some-
times
referred
to
as
the
automatic
transmission
range
switch
.
"
The
EWS
11
system
is
also
sometimes
referred
to
as
the
Driveaway
Protection
System
or
the
electronic
im-
mobilization
system
.
"
All-Season
Traction
(AST)
is
also
sometimes
referred
to
as
ASC
or
ASC+T
.
COMPONENT
LOCATIONS