Harness BMW 540i 1997 E39 Repair Manual

Downloaded from www.Manualslib.com manuals search engine
.-
ignition System
Disabling ignition system
The ignition system operates in a lethal voltage range and
should be disabled any time engine service or repair work is
being done that requires the ignition to be switched on.
The engine management system can be disabled by remov-
ing the DME main relay. The relay is located in the electronics
box (E-box) in the left rear of the engine
compartment, be.
neath the interior microfilter housing.
CAUTION- Relay locations may
vary. Use care when identifying relays.
See
610 Electrical Component Locations.
Checking for spark
CAUTION-
If
a spark test is done incorrecth damage to the Engine Con-
trol Module
(ECM) or the ignition coils may result.
NOTE-
Spark plug replacement is covered in 020 Maintenance.
Check~ng for spark is d~fflcult on englnes wlth d~str~butorless
ignition systems.
Try removing the spark plugs and inspecting for differences between them.
A poor-firing plug may be wet with fuel and/or ~. - ~
black and sooty, but not always. If a coil is not operating, the
engine management system will electrically disable the fuel
injector to that cylinder. The key is to look for differences be-
tween cylinders.
Ignition coil assembly, testing and
replacing
C4 UTION-
Use a digital multimeter for the following tests. I
- Remove plastic engine cover from top of valve cover by pry-
ing off bolt covers and removing cover mounting bolts.
- Raise car slowly while constantly checking position of jack
and car.
- Disconnect harness connector from coil. Connect multimeter
between terminal 15
(+) in connector and ground.
4 Terminal identification are typically molded into connector. In
photo, terminals are from left to right: 1,
4a, 15.

Downloaded from www.Manualslib.com manuals search engine
120-1 2
ignition System
Crankshaftspeedsensor
Crankshaft speed sensor, replacing (M52, M52 TU and
M54 engines)
4 Crankshaft speed sensor for 6-cylinder engine is mounted in
the left rear side of the cylinder block below the starter (ar-
row). The sensor reads a toothed pulse wheel mounted to
the end of the crankshaft.
- if the Engine Control Module (ECM) does not receive a signal
from the crankshaft speed sensor during cranking, the en-
gine will not start.
- If the OBD II svstem misfire detection ~rotocol detects a cat- - - ~~
alysr oarnagin; faLlt oJe to a ma I-nclion in crandshafi speeo
sensor components. Ine Check Engine
lignr (Malfuncrion In-
dicator Light or MIL) will be illuminated.
NOTE-
If the crankshaft speed sensor pulse wheel is damaged, the
engine will have to be disassembled down to the crankshaft
to
reolace the wheel.
- Make certain ignition has been turned off.
- Raise car and support in a safe manner.
WARNING -
Make sure the car is stable and well supported at all times.
Use a professional automotive lift orjacltstands designed for
the ouroose.
A floor iaclc is not adequate support.
- Remove under engine splash guard
4 Working underneath starter:
Cut off wire tie securing crankshaft speed sensor harness
connector (arrow) to sensor.
* Disconnect harness connector.
4 Remove sensor mounting fastener (arrow) and remove sen-
sor from cylinder block.
- Installation is reverse of removal, noting the following:
Use a new O-ring when installing sensor.
Be sure wiring is routed in same orientation.
Secure sensor using new wire ties.
Use scan tool to read out and clear ECM fault memory.

Downloaded from www.Manualslib.com manuals search engine
ignition System
Crankshaft speed sensor, replacing (M62 and M62TU
engines)
The crankshaft speed sensor reads a toothed pulse wheel
mounted on the flywheel.
If the Engine Control Module(ECM)
does not receive an impulse signal from the crankshaft speed
sensor during
cranking, the engine will not start. If the OBD II
system misfire detection protocol detects a catalyst damag-
ing fault due to a malfunction in the crankshaft speed sensor
components, the Check Engine light (Malfunction
Indicator
Light or MIL) will be Illuminated.
4 The crankshaft speed sensor (arrow) is mounted in the right
lower side of the bell housing.
- Remove speed sensor by disconnecting electrical harness
connector and unbolting sensor from bell housing. Do not
discard shims, if present.
- Installation is the reverse of removal. Clean mounting surface
before installing new sensor, and install shims, if present.
< If the flywheel was replaced, the speed sensor must be
checked for correct installation depth.
* Crank engine in direction of rotation using crankshaft bolt
until a full pulse tooth is centered in the opening for the re-
moved speed sensor.
Measure depth ro top of tooth from speed sensor p~lse
generator mounting s~rface on transmission.
4 Measure length of pulse generator from mounting surface to
end (A).
- Subtract length of pulse generator (A) from distance to pulse
tooth from mounting area on transmission. This measure-
ment is the gap between the pulse sensor and flywheel. Use
shims available from BMW to increase gap as needed to
reach specification.
Pulse sensor
gap
End of sensor to flywheel teeth 0.55 + 0.2 rnrn
(0.0217 t 0.008 in)

Downloaded from www.Manualslib.com manuals search engine
I Ignition System
Camshaft position sensors
The camshaft position sensors are used by the englne man-
agement system for VANOS control, sequential fuel injection
and knock control.
Intake camshaft position sensor, replacing
(M52,M52 TU
and M54 engines)
- Make certain ignition has been turned off.
- Remove plastic cover from above fuel injectors by prying off
bolt covers and removing cover mounting bolts.
Remove complete air filter housing:
Disconnect electrical harness connector on mass air flow
sensor
(A).
Detach vacuum line at intake boot (B).
Loosen hose clamp at intake boot and detach air duct con-
nections
(C).
* Disconnect cold air duct tube (D).
Remove filter housing mounting screws (E).
- Disconnect harness connector from VANOS solenoid and
unscrew solenoid from VANOS control unit. Be prepared with
shop rags to catch oil released from VANOS unit.
Remove camshaft sensor (arrow) from
left front of cyl~nder
head, next to top of oil filter housing.
Disconnect camshaft sensor harness from under intake
manifold. Prior to removal, attach a stiff piece of wire to the
harness connector end to preserve proper routing of harness
for reinstallation.
Installation is reverse of removal, noting the following:
Use new O-rings when installing sensor and solenoid.
Be sure wiring is rerouted in same orientation.
Use scan tool to read out and clear
ECM fault memory
Tightening torques
-
Intake camshaft sensor to cylinder head 10 Nrn (7 ft-lb)
VANOS solenoid to VANOS control unit 30 Nm (22 ft-lb)

Downloaded from www.Manualslib.com manuals search engine
120-15
Ignition system1
Exhaust camshaft position sensor, replacing
(M52 TU and M54 engines)
- Make sure ignition has been turned off.
4 Working at front of engine on exhaust (right) side, detach ex-
haust camshaft position sensor electrical harness connector
(arrow) and remove sensor.
- Installation is reverse of removal, noting the following:
Use a new O-ring when installing sensor.
- Use scan tool to read out and clear ECM fault memory.
Tightening torque
Exhaust camshaft sensor
to cylinder head 10 Nm (7 ft-lb)
Intake camshaft position sensor, replacing
(M62 and M62 TU engines)
- Make sure ignition has been turned off
4 Remove top engine cover by releasing quick release fasten-
ers (arrows) by pressing down.
4 Remove air filter housing and mass air flow sensor:
Disconnect mass air flow sensor and
intalte air tempera-
ture sensor electrical harnesses
(A and B).
Remove air filter housing mounting fastener (arrow).
Loosen hose clamps
(C and D).
Remove hose at idle air stabilizer.
Remove air filter housing with mass air flow sensor.
- Remove intalte hose from throttle body.

Downloaded from www.Manualslib.com manuals search engine
120-1 6
Ignition System
Remove camshaft sensor (arrow) from front of right cylinder
head.
Disconnect camshaft sensor harness from cable duct above
right cylinder head.
Installation is reverse of removal, noting the following:
Use new O-ring when installing sensor.
Be sure wiring is rerouted in same orientation.
Use scan tool to read out and clear ECM fault memory.
Tightening torque Intake camshaft sensor to timing chain 5 Nm
(3.5 ft-lb)
cover
Knock sensors
Knock sensors, replacing (M52, M52 TU and M54
engines)
The knock sensors are bolted to the left side of the cylinder
block under the intake manifold.
- Remove intalte manifold as described in 113 Cylinder Head
Removal and Installation.
D~sconnect knock sensor electrical harness connector (A) on
left side of engine cylinder block.
Remove knock sensor
mount~ng bolts (arrows) on side of
cyllnder block. Remove sensors.
Note the installed angle of the
lnocl~ sensor on the bloc/( be-
fore removing it. Reinstall the sensor
in the same position. Be
sure to use a torque wrench when tightening the sensor
mounting bolt.
< Clean lknock sensor contact surface on engine bloclc and
sensor (arrows) before installing
ltnock sensor.
Tightening torque
Knock sensor to head 20 Nm (15 ft-lb)
- Use scan tool to read out and clear ECM fault memory.
Knock sensors, replacing
(M62 and M62 TU engines)
The
knock sensors are bolted to the side of the cylinder block
under the
intake manifold.

Downloaded from www.Manualslib.com manuals search engine
121-10
I Battery, Starter, Alternator
- Strip approximately 15 rnm (0.6 in) of insulation from cable
end.
terminal harness
Shrink insulation
Terminal connector
4 Push terminal connector of new cable over stripped end of
old cable. Tighten clamp.
- Slip shrink-fit insulation over positive cable. Attach new safe-
ty harness to end of positive cable. Shrink insulation with hot
air blower.
- Reinstall cable in cable bracket and attach to battery.
- Reattach negative battery cable. Reinstall luggage cornpart-
rnent trim pieces.
- Use BMW scan tool DlSplus or equivalent to read out airbag
control module fault memory. Correct faults, then clear mem-
ory.
1 1 4 Various versions of alternators have been used in E39
vehicles. See Table e.
Table e. Alternator application chart
Model Alternator type
Air cooled, 90 amp or 120 amp
Air cooled, with multi-function control
(MFR), 120 amp or 140 amp
Air cooled with multi-function control
(MFR), 120 amp or 140 amp
540i 1997 Air
cooled. 120
amp or 140amp sazrz~orsl 1998 ~~~ ~ .~ . ...~ ~ ~-~~~~ Air cooled; with integrated mu~ii-
function control (MFR). 120 amp 140
amp 1999-2002 Water
cooled, with integrated multi-
function control (MFR), 90-150 amp
(variable output)

Downloaded from www.Manualslib.com manuals search engine
Battery, Starter, ~lternatorl
Charging system quick-check
Use a digital multimeter to measure voltage across the bat-
tery terminals with key off and then again with engine running.
Battery voltage should be about 12.6 volts with key off and be-
tween 13.5 and 14.5 volts with engine running.
NOTE-
The regulated voltage (engine running) should be between
13.2 and 14.5, depending on temperature andoperating con-
ditions.
If the voltage is higher than 14.8, the voltage regula-
tor or
mulitfunction controller is most likely faulty
Check for clean and tight battery cables. Check ground cable
running from negative
(-) battery terminal to chassis and
ground cable running from engine to chassis. Check alterna-
tor drive belt condition and tension.
Charging system, checking
CAUTIOI\C
* Do not disconnect the battery while the engine is running.
Damage to the alternator and/or engine electronic systems
may result.
Only use a digital multimeter when testing charging
system components.
--7
4 Turn ignition key on. Check that battery warning light comes
on.
NOTE-
If the warning light does not come on, repair bulb or wiring
faults before continuing to checlc the charging system.
/ Charge indicator
502820805
4 6-cylinder engines only, remove complete air filter housing:
Loosen
intake duct hose clamp (A) at throttle assembly.
Loosen clamp and remove idle control hose from intake
duct
(B) and disconnect idle speed control valve electrical
harness connector.
Disconnect electrical harness connector
(C) from mass air
flow sensor.
Remove air filter housing mounting screw
(D).
Disconnect vent tube (E).
Loosen air intake duct clamp (F).
Carefully lift air filter housing out of engine bay.

Downloaded from www.Manualslib.com manuals search engine
- -
/Battery, Starter, Alternator -- - -. - --I
< Check for battery voltage at alternator terminal 30 (B+) (ar-
row):
Pull back rubber insulating cover at terminal 30 at rear of
alternator.
Connect voltmeter between terminal 30 and ground and
check for battery voltage.
If voltage is not present, check
wiring for faults.
NOTE-
On V-8 engines, access to the rear of the alternator is limited.
Check for battery voltage between the jump start post on the
left cylinder head and ground.
r Disconnect harness connector from alternator. Turn ianition
on and check for battery voltage between terminal
lgand
ground. If voltage is not present, check wiring and fuses for
faults.
Reconnect connector to alternator.
Locate the blue wire coming from terminal
61E of the alter-
nator connector. Carefully connect the positive
(+) test lead
to the wire using a piercing test lead end.
Turn ignition key on and check for voltage. Voltage should be
less than 1.5 VDC and charge indicator lamp should light.
- Making sure all test equipment and tools are clear, start en-
gine. Voltage should increase to
8.0 VDC or higher. The
charge indicator light should go out.
If voltage does not increase and system is not charging,
the fault is in alternator.
- If voltage does not increase, but system is charging, inter- - roaate svstem for faults usina an appropriate BMW scan - .. . tool and'reset fault memory.
- If a load tester is not available, a quick alternator output test
can be done by running engine at about 2000 rpm and turn-
- -
ing on electrical loads (fans, lights, rear window defroster, -
- and wipers). With all accessories on, battery voltage should
be above 12.6
V.

Downloaded from www.Manualslib.com manuals search engine
Battery, Starter, ~lternatorl
Alternator, removing and installing
(6-cylinder engine)
A replacement alternator should have the same rating as the
original. Alternator manufacturer and ampere rating are nor-
mally marked on the alternator housing.
- Disconnect negative (-) battery cable.
CAUTION-
Prior to disconnecting the batteg read the battery discon-
nection cautions given
in 001 General Warnings and Cau-
I tions.
Remove complete air filter housing:
Loosen intake duct hose clamp
(A) at throttle assembly.
Loosen clamp and remove idle control hose from intake
duct
(B) and disconnect idle speed control valve electrical
harness connector.
Disconnect electrical harness connector
(C) from mass air
flow sensor.
* Remove air filter housing mounting screw (D),
Disconnect vent tube (E).
Loosen air intake duct clamp (F).
Carefully lifl air filter housing out of engine bay.
Remove alternator drive belt. See belt removal procedures in
020 Maintenance.
- Remove radiator cooling fan and fan shroud. See 170 Radi-
ator and Cooling System.
NOTE-
The radiator cooling fan nut (32 mm wrench) has left-hand
threads.
- Unbolt power steering fluid reservoir and bracket. Suspend to
one side without detaching fluid hoses.
- Disconnect alternator air cooling tube.
- Disconnect wiring from rear of alternator.
'4 Remove upper and lower mounting bolts (arrows) and lift
alternator.
If idler pulley for belt interferes, remove pulley cover and
retaining bolt to remove pulley. out