BMW X5 2001 E53 M54 Engine User Guide

11
M54engMS43/ST036/6/20000
MS 43 NEW FUNCTIONS
ACCELERATOR PEDAL SENSOR
The accelerator pedal sensor is similar to the PWG used on the ME 7.2 system. It is inte-
grated into the accelerator pedal housing. Two hall sensors are used to provide the driver’s
input request for power.
The hall sensors receive power (5 volts) and ground from the MS 43 control module and
produce linear voltage signals as the pedal is pressed from LL to VL.
PWG SENSOR 1 = 0.5 to 4.5 V
PWG SENSOR 2 = 0.5 to 2.0 V
The MS 43 control module uses the
signal from sensor 1 as the driver’s
request and the signal from sensor 2
as plausibility checking.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
HS
12 3 4 5
MS 43.0
HS
SIGNAL 1
SIGNAL 2
HALL SENSOR
POWER
61460015

12
M54engMS43/ST036/6/2000
MS 43 NEW FUNCTIONS
ACCELERATOR PEDAL SENSOR
PWG SIGNAL MONITORING & PWG FAILSAFE OPERATION:
• As a redundant safety feature the PWG provides two separate signals from two integral
angle hall sensors (HS #1 and HS #2) representing the driver’s request for throttle acti-
vation.
• If the monitored PWG signals are not plausible, MS 43.0 will only use the lower of the
two signals as the driver’s pedal request input providing failsafe operation. Throttle
response will be slower and maximum throttle position will be reduced.
• When in PWG failsafe operation, MS 43.0 sets the EDK throttle plate and injection time
to idle (LL) whenever the brake pedal is depressed.
• When the system is in PWG failsafe operation, the instrument cluster matrix display will
post “Engine Emergency Program” and PWG specific fault(s) will be stored in memory.
_____________________________________________________________________________
_____________________________________________________________________________
E46ICPOT-SIG.

13
M54engMS43/ST036/6/20000
MS 43 NEW FUNCTIONS
EDK THROTTLE POSITION FEEDBACK SIGNALS
The EDK throttle plate is monitored by two integrated potentiometers. The potentiometers
provide linear voltage feedback signals to the control module as the throttle plate is opened
and closed.
Feedback signal 1 provides a signal from 0.5 V (LL) to 4.5 V (VL).
Feedback signal 2 provides a signal from 4.5 V (LL) to 0.5 V (VL)
Potentiometer signal 1 is the primary feedback signal of throttle plate position and signal 2
is the plausibility cross check through the complete throttle plate movement.
ART-EDK.EPS1
ART-E46ICPWG2.

14
M54engMS43/ST036/6/2000
MS 43 NEW FUNCTIONS
EDK THROTTLE POSITION FEEDBACK SIGNALS
EDK FEEDBACK SIGNAL MONITORING & EDK FAILSAFE OPERATION:
• The EDK provides two separate signals from two integral potentiometers (Pot 1 and Pot
2) representing the exact position of the throttle plate.
• EDK Pot 1 provides the primary throttle plate position feedback. As a redundant safe-
ty feature, Pot 2 is continuously cross checked with Pot 1 for signal plausibility.
• If plausibility errors are detected between Pot 1 and Pot 2, MS 43.0 will calculate the
inducted engine air mass (from HFM signal) and only utilize the potentiometer signal that
closely matches the detected intake air mass.
- The MS 43.0 uses the air mass signalling as a “virtual potentiometer” (pot 3) for a
comparative source to provide failsafe operation.
- If MS 43.0 cannot calculate a plausible conclusion from the monitored pots (1 or 2
and virtual 3) the EDK motor is switched off and fuel injection cut out is activated
(no failsafe operation possible).
• The EDK is continuously monitored during all phases of engine operation. It is also
briefly activated when KL 15 is initially switched on as a “pre-flight check” to verify it’s
mechanical integrity (no binding, appropriate return spring tension, etc). This is accom-
plished by monitoring both the motor control amperage and the reaction speed of the
EDK feedback potentiometers. If faults are detected the EDK motor is switched off and
fuel injection cut off is activated (no failsafe operation possible). The engine does how-
ever continue to run extremely rough at idle speed.
• When a replacement EDK is installed, the MS 43.0 adapts to the new component
(required amperage draw for motor control, feedback pot tolerance differences, etc).
This occurs immediately after the next cycle of KL 15 for approximately 30 seconds.
During this period of adaptation, the maximum opening of the throttle plate is 25%.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________

15
M54engMS43/ST036/6/20000
MS 43 NEW FUNCTIONS
MAIN RELAY MONITOR
The MS 43.0 system incorporates a new monitoring feature for terminal 87 (KL 87) of the
main relay. The relay is monitored internally for the voltage level at KL 87. Five seconds after
the ignition key is switched on, and the voltage at the KL 15 input is greater than 9 volts,
the control module checks the voltage at KL 87.
If the voltage difference between the two terminals is greater than 3 volts, a fault will be
stored in the ECM.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
ART-E46ICMS43RELAY

16
M54engMS43/ST036/6/2000
MS 43 NEW FUNCTIONS
EMISSION OPTIMIZED - IGNITION KEY OFF
“Emission Optimized Ignition Key Off” is a programmed feature of the MS 43 control mod-
ule.
After the ECM detects KL 15 being switched OFF, the ignition stays active for two more
individual coil firings. This means that just two cylinders are fired - not two revolutions.
This feature allows residual fuel injected into the cylinders, as the ignition key is switched
off, to be burned as the engine runs down.
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
ART-E46ICEMIOPT

17
M54engms43/STO36/6/2000
MS 43 NEW FUNCTIONS
DM-TL (DIAGNOSIS MODULE - TANK LEAKAGE)
The M54 engine with the Siemens MS43.0 engine control system uses the DMTL system
for fuel system leakage monitoring. The pump is manufactured by Bosch for use with the
Siemen’s control system.

18
M54engms43/STO36/6/00
123
DM-TL (DIAGNOSIS MODULE - TANK LEAKAGE)
FUNCTIONAL OVERVIEW:
The DM-TL is located in the drivers side rear wheel well in the X5 and next to the charcoal
canister on the E46 - M54.
1. In it’s inactive state, filtered fresh air enters the evaporative system through the sprung
open valve of the DM-TL.
2. When the DME activates the DM-TL for leak testing, it first activates only the pump
motor. This pumps air through a restrictor orifice (1.0 or 0.5 mm) which causes the elec-
tric motor to draw a specific amperage value. This value is equivalent to the size of the
restrictor.
3. The solenoid valve is then energized which seals the evap system and directs the pump
output to pressurize the evap system.
The evap system is detected as having a large leak if the amperage value is not realized, a
small leak if the same reference amperage is realized or no leak if the amperage value is
higher than the reference amperage.

19
M54engMS43/ST039/3/17/00
DM-TL (DIAGNOSIS MODULE - TANK LEAKAGE)
FUNCTION
The DC Motor LDP ensures accurate fuel system leak detection for leaks as small as
0.5mm (.020”). The pump contains an integral DC motor which is activated directly by the
engine control module. The ECM monitors the pump motor operating current as the mea-
surement for detecting leaks.
The pump also contains an ECM controlled change over valve that is energized closed dur-
ing a Leak Diagnosis test. The change over valve is open during all other periods of oper-
ation allowing the fuel system to “breath” through the inlet filter (similar to the full down
stroke of the current vacuum operated LDP).

20
M54engMS43/ST039/3/17/00
LEAK DIAGNOSIS TEST PRECONDITIONS
The ECM only initiates a leak diagnosis test every second time the criteria are met. The cri-
teria is as follows:
• Engine OFF with ignition switched OFF.
• Engine Control Module still in active state or what is known as “follow up mode” (Main
Relay energized, control module and DME components online for extended period after
key off).
• Prior to Engine/Ignition switch OFF condition, vehicle must have been driven for a min-
imum of 20 minutes.
• Prior to minimum 20 minute drive, the vehicle must have been OFF for a minimum of 5
hours.
• Fuel Tank Capacity must be between 15 and 85%(safe approximation between 1/4 -
3/4 of a tank).
• Ambient Air Temperature between -7
OC & 35OC(20OF & 95OF )
• Altitude < 2500m(8,202 feet).
• Battery Voltage between 11.5 and 14.5 Volts
When these criteria are satisfied every second time, the ECM will start the Fuel System Leak
Diagnosis Test. The test will typically be carried out once a day i.e. once after driving to
work in the morning, when driving home in the evening, the criteria are once again met but
the test is not initiated. The following morning, the test will run again.