2000 BMW 528i idle control

Downloaded from www.Manualslib.com manuals search engine
--
Fuel Injection I
The PWG potentiometers provide DC voltage signals as in-
put to the ME 7.2 control module for throttle and idle control
functions. Potentiometer signal
1 is the primary signal, poten-
tiometer 2 is used for a plausibility cross-check.
1. Potentiometer 1 ground
2. Potentiometer
1 power
3. Potentiometer 2 ground
4. Potentiometer 2 power
5. Potentiometer 1 signal to ECM
6. Potentiometer 2 signal to ECM
If errors are detected between potentiometer
1 and 2, the
ECM calculates the engine intake air mass (from
MAFsensor
signal) and only utilizes the potentiometer signal that closely
matches the detected
intake air mass. The ECM control mod-
ule uses the air mass signal for a comparative source to pro-
vide fail-safe operation.
If the ECM cannot calculate a
plausible conclusion from the monitored potentiometerthe
EDK motor is switched off and fuel injection cut-out is activat-
ed (no fail-safe operation possible).
EDK is continuously monitored during all phases of engine
operation. If faults are detected, the EDK motor is switched off
and fuel injection cut off is activated. The engine continues to
run extremely roughly at idle speed.
EDK adaptation
When the EDK throttle assembly is replaced, the adaptation
values of the previous EDK must be cleared from the ME 7.2
ECM using the BMW service testeroran equivalentscan tool.
Once the old adaptation values have been cleared, the new
EDK assembly should be installed and adapted as follows:
0 Switch ignition OFF for 10 seconds.
* Switch ignition ON. Afler approximately 30 seconds, the
EDK is briefly activated indicating that the replacement unit
is now adapted to the ME 7.2 system.
NOTE-
This EDK adaptation procedure is also necessary after re-
placing the
ME 7.2 engine control module. However, the ad-
aptation values do not require clearing since they have not
yet been established.
ECM relay, testing
The engine control module (ECM) relay is energized via the
ECM and supplies battery positive
(B+) power to many of the
engine management components and subsystems. If this re-
lay is faulty, the engine will not start.
NOTE-
The ECM relay is also referred to as the DME main relay

Downloaded from www.Manualslib.com manuals search engine
130-74
I Fuel Injection
Evaporative system pressure leak
diagnosis, overview
The M62 TU engine is equipped wlth an evaporative fuel sys-
tem pressure leak diagnosis system. The main component of
this system is the leakdiagnosis pump (LDP). The function of
the LDP is to pressurize the fuel tank and the evaporative
emission system for the purpose of detecting leaks.
This system iscapable of detecting a
lealcas small as0.5 mm.
The LDP, located in the left rear wheel housing, contains the
following:
Vacuum chamber. Pneumatic pump chamber
DME activated vacuum solenoid
Reed switch (provides switched voltage
feedback signal to
DME).
The vacuum supply line is in the wiring harness from the en-
gine compartment and runs down the driver's side of the vehi-
cle.
The canister vent valve is
~ntegrated into the LDP, which IS
electrically controlled by the ECM. The canister vent valve is
opened to provide fresh air entry into the fuel system only dur-
ing purge operation.
- Purge operation characteristics:
Off idle through full throttle: purge valve opened by pulse
width modulated (PWM) control of the ECM. PWM duty cy-
cle varies by engine operating conditions
(e.g. warm idle,
purge valve opened slightly; cold
idleldecel with engine
temp
< 67" C. purge valve always closed).

Downloaded from www.Manualslib.com manuals search engine
130-75
Fuel Injection
Secondary air injection, overview
The secondary air system pumps ambient air into the exhaust
stream afteracoid engine start to reduce the warm-up time of
the catalytic converters and to reduces HC and CO emis-
sions. The ME
7.2 ECM controls and monitors the secondary
air injection system. The secondary air pump operates at a
starttemperature of between 10°C
(50°F) and 40°C (104°F).
and continues to operate for a maximum of
2 minutes at idle
speed.
The electric air pump draws in ambient air and supplies it to
the
checlc valve. The vacuum vent valve (solenoid) switches
vacuum to open the
checlc valve when activated by the ECM.
Once opened, the checlc
valve allows air to be pumped into
the exhaust stream.
4 The secondary air injection system consists of the following
components:
1. Secondary air pump relay
2. Oxygen sensors
3. Catalytic converters
4. Electric air pump
5. Non-return valve
6. Vacuum vent valve

Downloaded from www.Manualslib.com manuals search engine
300-1 0
/Suspension, Steering and Brakes - General
The steering system features variable power assist provided
by an engine-driven hydraulic pump.
Rack and pinion steering
6-cylinder models
(525i, 5281, 5300
Two types of steering systems are used in E39 models. 6-
cylinder (525i, 5281, 530i) models are equipped with a steer-
ing rack system. V-8
(540i) models are equipped with a re-
circulating ball and nut steering gearbox.
Rack-and-pinion steering
Steering components in 6-cylinder models consist of a rack-
and-pinion type steering gear and connecting linltage to the
road wheels.
The steering linkage connects the rack-and-pinion unit
through tie rods to the steering knucltles. The tie rod ends al-
low the wheels to pivot and react to suspension travel.
Recirculating ball and nut steering
V-8 models
(540i)
I
Recirculating ball and nut steering
Recirculating ball and nut steering in V-8 models consists of a
steering box with integrated hydraulic control valve and con-
necting linkage to the road wheels.
Thesteering linkageconnects the steering gearbox through a
pitman arm to the wheels. An idler arm maintains correct toe
angle. The tie rod allow the wheels to pivot and react to sus-
pension travel.
E39 cars are equipped with power disc brakes with integral
antilock brakes (ABS). The parking bralte is a dual-drum sys-
tem integrated with the rear brake rotors.
Power assist is provided by a vacuum booster when the en-
gine is running. The brake pedal
pushrod is connected direct-
ly to the master cylinder, so failure of the vacuum booster
does not normally result in total
bralte failure.
Each disc bralte uses a caliper with a single hydraulic cylin-
der. Brake pads in the left front and right rear contain wear
sensors. When brake pads need replacement, the sensors il-
luminate a light on the dashboard.

Downloaded from www.Manualslib.com manuals search engine
31 0-4
I Front Suspension
6-cylinder models
12 3 4 5
V-8 models
16 7 4
Front suspension
variations
1. Steering knuckle
2. Tension strut (thrust arm)
3. Steering rack
4. Front suspension
subframe
5. Outer tie rod
6. Control arm
7. Steering box
8. Idler arm
9. Center tie rod
The front suspension
shoclc absorbers on E39 cars are
MacPherson struts. The strut is a major component of the
front suspension and supports the spring. Most strut assem-
bly components are available as replacement parts. Always
replace struts and springs in pairs.
Front strut, upper strut mount or spring replacement is a two-
step procedure:
Removal of strut assembly from vehicle
Disassembly and replacement of component on
work
bench

Downloaded from www.Manualslib.com manuals search engine
I Steering and Wheel Alignment
I I 4 Gap A = 0.5 - 8.5 mm (0.02 - 0.33 in)
- Reinstall inner control arm bolts
Tightening torques
Control arm to
subframe 78 Nm (58 it-lb)
(tighten with wheel on ground)
Pitman arm pinch bolt (note direction of threads) 61 Nm (45 ft-lb)
Steering idler arm, removing and installing
The idler arm is bolted to the subframe through a bushing.
The bushing is subject to wear and is available as a replace-
ment part.
- Raise front of car. Remove splash shield from under engine.
WARNING -
Male sure the car is firmly supported on jaclc stands de-
signed for the purpose. Place jack stands beneath structural
chassis points. Do not place jack stands under suspension
parts.
4 Remove center tie rod fastener and press tie rod out of idler
arm with
BMW special tool 32 1 190.
- Remove idler arm mounting bolt through opening in sub-
frame and remove idler arm from car.
- Installation is reverse of removal.
Make sure all thread bores, bolts, nuts and mating surfac-
es are clean.
Use new self
loclting nuts to mount idler arm to subframe
and center tie rod to idler arm.
If idler arm or idler arm bushing is replaced, adjust
pitman
arm as described earlier.
Have car professionally aligned.
Tightening torques
Center tie rod to idler arm 65 Nm (48 ft-ib)
(replace self-locking nut)
Idler arm to front subirame
(replace self-locking nut) 62
Nm (46 it-lb)

Downloaded from www.Manualslib.com manuals search engine
OBD-8
I On-Board Diagnostics
DTC digit interpretation
1st digit
P powertrain
B body
C chassis
2nd digit
0 SAE
1 BMW
3rd digit
0
1
2
3
4
5
6
7
4th - 5th digits total
system
airlfuei induction
fuel injection
ignition system or misfire
auxiliary emission control
vehicle speed
& idle control
ECM
inputs/outputs
transmission
individual circuits or
components
DTC example: P 0 3 0 6
P: A powertrain problem
0: SAE sanctioned or 'generic'
a 3: Related to an ignition system / misfire
06 Misfire detected at cylinder #6
DTCs provide a freeze frame or snap-shot of a vehicle
performance or emissions fault at the moment that the fault
first occurs. This information is accessible through generic
OED I1 scan tools.
Freeze frame data contains, but is not limited to, the following
information:
Engine load (calculated)
Engine rpm
Short and
long term fuel trim
Vehicle speed
Coolant temperature Intake manifold pressure
Open/closed loop operation
Fuel pressure (if available)
DTC

Downloaded from www.Manualslib.com manuals search engine
OBD-15
On-Board ~iagnosticsl
Engine diagnostic trouble codes: M52 engine (continued)
P-code
PO340
PO412
PO420
PO430
PO440
PO441
PO442
PO443
PO500
PO505
PO600
PO601
PO601
I PO601
~1132
~1133
BMW-FC
65
62
233
234
250 144
-
145
68
214
i I
DTC Definition
Camshalt Position Sensor 'A' Circuit (Bank 1 or Single Sensor)
Secondary Air Injection System Switching Valve A Circuit
Catalyst System Efficiency Below Threshold
(Bank 1)
Catalyst System Efficiency Below Threshold (Bank 2)
Evaporative Emission System
Eva~orative Emission Svstem Incorrect Purge Flow .
Evaporative Emission System Leak Detected (small leak)
Evaporative Emission System Purge Control Valve Circuit
Vehicle Speed Sensor 'A'
204
21 7
100
170
171
188
189
PI161
PI180
PI181
PI184
PI185
PI178
02 Sensor Heater Control Circuit (Bank 2 Sensor 2) I
idle Air Control System
Serial Communication
Link
Internal Control Module Memory Check Sum Error
Internal Control Module Memory
Check Sum Error
Internal Control Module Memory
Check Sum Error
02 Sensor Heater Control Circuit (Bank 1 Sensor
1)
02 Sensor Heater Control Circuit (Bank 2 Sensor 1)
Mass or Volume Air Flow Circuit RangeIPerlormance Problem PI140
I
I I
P1188 1227 I Fuel Control (Bank 1 Sensor 1)
PI145 150 /Solenoid Valve Running Losses Control Circuit Electrical
149
122
223
224
220 221
231
I I
P1189 1228 I Fuel Control (Banlc 2 Sensor 1)
Fuel Trim Adaptation Additive High (Bank 2) (M52: Engine Oil Temperature Sensor Circuit)
02 Sensor Signal Circuit Slow Switching from Rich to Lean
(Bank 1 Sensor 2)
02 Sensor Signal Circuit Slow Switching from Rich to Lean
(Bank 2 Sensor 2)
H02S Sensor Voltage Excursion Electrical (Banlc 1 Sensor 1)
HO2S Sensor Voltage Excursion Electrical (Banlc 2 Sensor 1)
02 Sensor Sianai Circuit Slow Switchina from Rich to Lean (Bank 1 Sensor 1)
02 Sensor Signal Circuit Slow Switching from Rich to Lean (Bank 2 Sensor 1) PI179
I I
PI190 1235 I Pre Catalyst Fuel Trim System (Banlc 1)
PI186 1190 102 Sensor Heater Control Circuit (Banlc 1 Sensor 2)
232
I I
PI191 1236 I Pre
Catalyst Fuel Trim System (Banlc 2)
PI192
. . -- - i Pi193 1226 I Post Catalvst Fuel Trim Svstem (Bank 2)
225
PI397
I I
Post Catalyst Fuel Trim System (Bank 1)
PI421 1246 /Secondarv Air System (Bank 2)
18
Secondary Air System (Bank
1) PI423
Camshaft Position Sensor '0' Circuit (Bank 1)
I 245