BMW Sensors Problems and Faults

Voluntary Emissions Recall Campaign No. 99E-A01

Model:
E36 – BMW 323i and BMW 328i with M52 engine produced June 1995 - December 1998
E36-BMW M3 with S52 engine produced January 1996 – December 1998
E39-BMW 528i with M52 engine produced March 1996 –August 1998
BMW Z3-with M52 engine produced July 1996 – September 1998
BMW Z3-with S52 engine produced January 1998 – January 1999
Complaint:
Vehicles that have a faulty crankshaft position sensor have had a Voluntary Emission-Recall Campaign. This is to check the illumination of the check engine lamp as well as fault code 83 – Crankshaft position sensor, and fault code 244 – Crankshaft segment timing.
Remedy:
The crankshaft position sensor should be replaced with the same sensor used on a M52TU engine. An adaptor harness must also be installed so that it has a 12V operating voltage instead of the 5 volts currently supplied by the DME.

Quality Monitoring M44/M62 Camshaft Sensor

Model:
E36 – BMW 318i/A/ti with M44 engine produced February 1996 to February 1997
E39 – BMW 540i/iA with M62 engine produced February 1996 to February 1997
E38 – BMW 740i/iA/iL with M62 engine produced February 1996 to February 1997
BMW Z3 – with M44 engine produced February 1996 to February 1997
Complaint:
The above listed models need to replaced with a new sensor and the old sensor must be sent back to the Warranty Parts Return Centre with a copy of any of the DME fault codes if they are present.
Based on the results of the Dealer Communications System the following procedure must be followed:
Remedy:
The customer’s permission and signature must be obtained before the procedure begins.
Read and print out DME fault codes if present. Ignore the camshaft sensor fault codes if they are present.
Clear all fault codes stored in the DME
Replace the camshaft sensor as outlined in the repair manual group.

No Start Caused by Faulty Oil Level Switch

Model:
BMW E39 (5series) with M52 engine, BMW E46 (3 series) Vehicles up to November 1998
Complaint:
The vehicle will not start, there is no crank. It may also be noticed that there is no transmission range display in the Instrument Cluster. The charge indicator lamp flickers or is permanently on. The oil level switch is stored in the Instrument Cluster (E46). Fuse 15 or Fuse 30 is blown.
This is due to a faulty oil level switch which causes the fuse to blow so there is a loss of input to EWS from the Transmission Range Switch.
Remedy:

-If Fuse 15 or Fuse 30 is blown then install a new fuse (7.5A), turn the ignition to attempt to start the engine.
-If the fuse blows again, disconnect the Oil Level Switch at the plug connector.
Install a new fuse and start the engine.
-If the engine starts, and the range display is shown in the Instrument Cluster then replace the Oil Level Switch.

In order to confirm a defective switch then use a DVM to check the resistance between the pins of the 3 pin connector. If the switch is good it should measure infinite resistance between any 2 pins in the connector.

Fault Code 227/228

Model:
E36 – BMW 328i with M52 engine
E39 – BMW 528i with M52 engine
Complaint:

The ‘Check Engine’ lamp is illuminated.
FC 227 – Mixture deviation, cylinder 1-3 and/or
FC 228 – Mixture deviation cylinder 4-6

Remedy:

Check the correct Air Mass Meter is installed. If the wrong one is installed then it needs to be replaced as well as the Suction Silencer. The rubber boot may not need replacing as it has a rubber ‘downsizing’ ring which is used for installing the smaller Air Mass Meter on other models. Remove the inner rubber ring from the rubber boot in order to install the larger Air Mass Meter.
If the correct air mass meter is installed then check the adaptation values located in the DME diagnostic status section. These values can provide a further insight into what has made the fault set.
After repairs are made relating to an adaptation related fault, the adaptation values should be cleared. This will allow the vehicle to driven under various load conditions and readapted. If the adaptation values are rechecked an indication of the success of the repair can be obtained.

Multiplicative mixture adaptation (Part Load) Vehicle under load

If the value is greater than 6% there may be an unmeterd air leak and not enough fuel is reaching the system, or an erroneous signal from the air mass meter. Then the oxygen sensor will measure a lean signal, which will cause the DME to compensate for the problem by trying to make the mixture rich.
If the value is less than -7% there could be an air restriction, erroneous signal from the air mass meter, or too much fuel in the system. The oxygen sensor signal will then measure a rich signal which causes the DME to compensate for the problem by making the mixture lean.

Additive mixture adaptation (Idle) Vehicle idle

If the value is greater than 0.2 ms then there is an unmeterd air leak where not enough fuel is being supplied to the system or an erroneous signal from the air mass meter. The oxygen sensor signal measures a lean signal which causes the DME to compensate and make the mixture too rich.
If the value is less than -0.2ms then there is an air restriction, and too much fuel is being supplied to the system or an erroneous signal from the air mass meter. The oxygen sensor signal measures a rich signal which causes the DME to compensate for the problem by making the mixture too lean.

Once a certain threshold (ms) value is exceeded the system can no longer offset the problem and a fault is logged.

Seal on 2 and 3 Pin Plug Connectors

Model:
All BMW
Complaint:
When connecting or disconnecting 2 or 3 pin plug connectors it is possible for the rectangular seal to fall out of the plug housing unnoticed. The seal prevents moisture from seeping into the plug as well as ensuring that the two halves of the plug are properly tensioned so that the contacts do not move within the plug. If this movement occurs the contacts can develop corrosion. Corroded or loose contacts could cause problems with the proper functioning of the vehicle, as well as causing difficulty in diagnosis due to the possibly intermittent nature of such problems.
Remedy:
Ensure that when working with 2 or 3 pin plug connectors the seal is in place before the plug connector is connected. If it is missing then it must be replaced.

Oil Pressure Warning Light Comes On

Model:
BMW E38 with M60, M62 and M73 Engines
Complaint:
During production an oil pressure switch wiring harness was installed which could let water into the electrical connector, which in turn will cause corrosion at the oil pressure switch pin connections. As a consequence of this corrosion the engine oil pressure warning light will come on, even if the oil pressure is fine.
Remedy:
The oil pressure switch and the oil pressure switch wiring harness needs to be replaced. This procedure will apply to vehicles produced before January 1996.

M52 Engine Control Module Fault Code 12

Model:
E36–BMW 328i and E39–BMW 528i with M52 Engine
Complaint:
Due to a software error in the DME results an erroneous setting of fault code 12 in the DME will occur. The customer can experience the ASC lamp being illuminated, the ‘check engine’ lamp is illuminated. The vehicle may also show Fault Code 12 (Throttle valve potentiometer in the DME), Fault Code 154 (CAN accelerator pedal setting in the EGS/AGS), and Fault Code 57 (Throttle valve signal from DME in ASC/ABS).
Remedy:
The Engine Control Module (DME) needs to be reprogrammed using the MODIC programming software version P9.0 or higher. Once the DME has been reprogrammed perform “Quick Clear” which will clear any faults that have been set as a result of the reprogramming. Next clear the “Throttle Position adaptation values” under service functions.

Oil Level Sensor

Model:
BMW E31 and E34 with M60 and M62 engines produced from January 1995 – January 1996.
Complaint:
As a result of a porous float in the level sensor assembly the engine oil level sensor may indicate an incorrect oil level.
Remedy:
Utilize the ‘Service Menu’ of the Dealer Communication System, and based upon the response of the system either proceed with corrective action, or take no action at all. If action is necessary then replace the oil level sensor on the affected vehicles.

Engine Control Module Fault Code for Throttle Position Sensor

Model:
BMW E34 and E36 with M50 engines
Complaint:
The ‘check engine’ light is on, and in automatic transmission vehicles the failure indicator for transmission control module is on, and the transmission operates in the failsafe mode.
Remedy:
The idle speed control valve is to be replaced if:

-The engine control module has a fault code 12 (M50), or fault code 73 (M50TU), and transmission control module fault code 105 (only automatic transmission vehicles) is experienced.
-The throttle position sensor and its circuit have tested good, and
-No other outside influence can be found. (These include the floor mat pushed up against the pedal, a misadjusted throttle cable, or a misadjusted cruise control actuator assembly).

Coolant Temperature Sensor (NTC)

Model:
BMW E34 (M5) produced from October 1992 to December 1992
Complaint:
During production of the S38 engines the incorrect NTC coolant temperature sensors with a blue connector housing and tin plated electrical contacts may have been installed. Due to the vehicles’ wiring harness which connects to the NTC have gold plated connectors the two metals can corrode which will cause implausible signals to be transmitted to the DME control module, and adversely affect the driving characteristics.
Remedy:
Utilize the ‘Service Menu’ of the Dealer Communication System, enter the chassis number of the vehicle involved and based upon the response of the system either proceed with corrective action, or take no action at all. If action is necessary then:

-Remove the NTC coolant temperature sensor plug which is mounted in the coolant pipe above the exhaust manifold–blue connector.
-If the contacts on the NTC coolant temperature sensor are tin-plated then replace with a new NTC sensor with gold-plated contacts.
-Top off coolant level if necessary.
-If the sensors on the NTC are gold-plated the sensor does not need to be replaced.

Incorrect Fuel Gauge Reading

Model:
BMW E36 (3 series) including BMW 318ti produced from January 1995
Complaint:
Due to the formation of a non-conducting deposit on the conductor surface of the fuel level sensor, the fuel gauge does not read full after re-fuelling, or the fuel gauge is erratic.
Remedy:
Remove and replace both fuel level sensors with “Gold system” sensors.

Fuel Gauge Stays Empty after Refuelling/Fuel Gauge Erratic

Model:
BMW Z3 Roadster/coupe, BMW M roadster/coupe (E36/7). Vehicles produced before December 15 2000
Complaint:
After refuelling the fuel gauge will stay on empty or the fuel gauge is erratic. This is caused by a non-conducting deposit being formed on the conductor surface of the fuel level sensor. For the Z3 from September 1998 and the M roadster/coupe FC 2 (Fuel sensor voltage plausibility) will be set in the Instrument Cluster.
Remedy:
Remove and replace the fuel level sensor with a ‘Gold system’ sensor referring to repair instructions 16 12 000.

Incorrect Fuel Gauge Reading

Model:
BMW E53 (X5) vehicles produced before August 17 th 2000.
Complaint:
After the tank has been filled the fuel gauge will either not read “full”, or the correct reading will only be shown once the ignition has been switched OFF and ON again. These faults will be stored in the Instrument Cluster:

- Fault Code 8 – Fuel tank sensor 1 (fuel –pump side) and/or
-Fault Code 9 – Fuel tank sensor 2 (without fuel pump)

These errors are caused by a non-conducting deposit being formed on the conductor surface of the fuel level sensor.
Remedy:
Using the DIS or MoDiC:
-Select diagnosis
-Select Function Selection/Complete Vehicle/Body/Displays and Information/Instrument Cluster.
-Select Test Plan
-Select 4 – Expert Mode/ Read Fault Memory to confirm fault codes 8 and/or 9 are set.
-Select 3 Service Functions/ 1 – Test Code
-Press ‘Test Code’ button to save test code.
-Print Diagnosis Report
-Remove and replace the right hand delivery unit and the left hand fuel level sensor. Refer to repair instructions 16 12 000 and 16 12 001.
-Also to ensure a correct installation of the left side sensor use the following procedure:
-Lubricate the small o-ring for the fuel transfer pipe to ensure the o-ring does not push out of position when the fuel transfer pipe is being installed.
-Lubricate the inside edge of the large o-ring seal, so that the fuel level sensor will slide easily into position.
-The fuel level sensor must be installed keeping the top flange square to the tank at all times. Rotate the sensor so that the lug is located above it’s recess, then push the sensor vertically down into position. It must NOT be installed at an angle.
-Using the DIS or MoDiC select 4 – Expert Mode/ Clear Fault Memory to clear the fault code memory.

Fuel Gauge Reads ¼ when Tank Is Full

Model:
BMW Z3 (E36/7) produced from September 1998 to April 1999
Complaint:
After refuelling the fuel gauge reads ¼ full, and will then move extremely slowly to read full. This is due to a software error in the Instrument Cluster.
Remedy:
Re-code the instrument cluster using DIS CD Version 18.0 or later:

-Select Coding/Programming/ZCS Coding/E36/Recoding/Kombi and then follow the on-screen instructions to complete the coding process.
-Recoding the instrument cluster will start an internal day counter. If the test3.1 contains a value greater than 0 indicates the instrument cluster will already contain the fix.

 Evaporative Emission Control – On Board Diagnostic System

Model:
E36 – BMW 318i and BMW Z3 with M44 produced from January 1997
E36 – BMW 328i produced from October 1995
E36 – BMW M3 produced from March 1996
E38 – BMW 740i/iL and BMW 750iL produced from May 1997
Complaint:
The ‘check engine lamp is illuminated, and one or more of the following faults are set in the Engine Control Module (DME):

-In the M52 Engine the complaints include the tank venting system, minor leak (Code 251), Tank ventilation (Code 252), Shut-off valve, activated charcoal filter, jammed shut (Code 253) or Tank venting system, major leak (Code 254).
-In the M44, M62 or M73 Engine the complaints include the tank venting system, major leak (Code 94), Shut –off valve, activated charcoal filter, jammed shut (Code 96) or Tank venting system, minor leak (Code 97).

Remedy:
The check engine lamp will only be illuminated if the fault is present during two consecutive drive cycles. To complete a check of these systems the vehicle needs to run in a way that allows these functions to work fully. Any attempt to duplicate the specific driving condition will be unsuccessful, thus it is recommended that the test modules through BMW specific test tools are utilized. One driving cycle includes engine start up - drive - engine shutoff and will test the:

-Evaporative system – component functional check
-Evaporative system leak detection
-Tank venting/shutoff valve operation
-Monitoring catalytic converter efficiency
-Secondary air induction operation

If a fault occurs due to a major leak or a minor leak being present then check if the fuel filler cap has been installed correctly. This can be easily detected if the cap can be easily pulled off. To clear the fault properly install the cap, printout the fault information, clear the fault, select service functions, select DME system test, select 3- Leakage diagnosis, tank venting system.
If the fault returns the system needs to be checked for further leaks using the Evaporative System Leak Test Pool with an A/C leak detector.
If NO leak is detected the following component checks need to be carried out:

-Check the fuel filler gasket has not been damaged.
-Check operation of purge valve.
-Check purge valve using a hand held vacuum pump to check the valve can hold a vacuum.
-Check the o-ring is properly installed.
-Check for any broken hose fittings in the expansion tank.
-Check the operation of the shut-off valve.
-Check the shut-off valve has been correctly installed into the charcoal canister.
-Check routing of hose going to the fuel tank pressure sensor. If the hose is pinched it should be rerouted or shortened.

If the fault occurs through the shut-off valve the following must be checked:

-The routing of the hose going to the fuel tank pressure sensor. If the hose is pinched it should be rerouted or shortened.
-The operation of the Shut-off Valve, Purge Valve and Fuel Tank Pressure Sensor should be tested.
-Remove the shut-off valve from the charcoal canister and look for obstructions which do not allow the valve to shut correctly.

Stabilant 22A Electrical Contact Enhancer

Model:
All BMW
Complaint:
Connectors which carry low current are more likely to form deposits which affect the resistance of the circuit through the plug connector. Depending upon the particular circuit these deposits can cause malfunctions and consequently activate warning lamps and check control indicators.
Remedy:
Part replacement can temporarily stop the problem.
If the connector is the problem then without disconnecting the connector measure the resistance of the circuit running through the connector to make sure the connector has a high resistance. A good resistor will have close to 0 ohms resistance.
Visually examine the male and female terminals in the connector housing by removing them. Look at the integrity of the wire crimps, and in some male terminals the integrity of the weld of the male pin to the terminal. Then reinstall.
With a zero residue electrical contact cleaner liberally spray the male and female connectors, and allow the air to dry.
Apply Stabilant 22A to both male and female terminals so they are saturated, and reconnect the connectors while they are still wet. When the Stabilant 22A dries it will leave a thin coating of polymer film which is conductive between mating surfaces, and is non-conductive between adjacent pins. It can also prevent the formation of more harmful deposits.

Service Action to Recode Instrument Cluster

Model:
BMW Z3 (E36/7) produced between August 1998 to May 1999
Complaint:
After filling with fuel the fuel gauge can show a low reading, then while driving can move to correct position.
Remedy:
Utilize the ‘Service Menu’ of the Dealer Communication System, enter the chassis number of the vehicle involved and based upon the response of the system either proceed with corrective action, or take no action at all. If action is necessary then:
Recode the instrument cluster using DIS CD Version 18.0 by
Connect the DIS or MoDiC III to the diagnostic connector, switch on the engine, select ‘Encoding ZCS (‘3’)’, select Series E36 (‘4’), Select recoding (‘1’), select Kombi (‘10’), follow the on screen instructions to complete.

Coolant Temperature Gauge Reads High Under Normal Operating Conditions

Model:
BMW M roadster (E36/7) All vehicles produced until June 1998
Complaint:
Under normal operating conditions the pointer on the coolant temperature gauge reads between the mid-way point and the mark above the mid-way point. This is due to a coding error during the vehicle assembly.
Remedy:
Do not replace any components instead:
Recode the instrument cluster using DIS CD Version 18.0 by
Connect the DIS or MoDiC III to the diagnostic connector, switch on the engine, select ‘Encoding ZCS (‘3’)’, select Series E36 (‘4’), Select recoding (‘1’), select Kombi (‘10’), follow the on screen instructions to complete.

Oxygen Sensor

Oxygen Sensor Update and DME Reprogramming

Model:
BMW E36 with M44 engine
Complaint:
Over time the oxygen sensors on these vehicles can develop poor internal electrical connections which will illuminate the check engine light. When this occurs possible fault codes set in the DME are:
Fault Code 10, Oxygen Sensor Pre Catalyst and/or
Fault Code 12, Oxygen Sensor Post Catalyst.
Remedy:
Utilize the ‘Service Menu’ of the Dealer Communication System, enter the chassis number of the vehicle involved and based upon the response of the system either proceed with corrective action, or take no action at all. If action is necessary then:
Replace both oxygen sensors (pre cat regulating sensor and post cat monitoring sensor) and using the DIS or MODIC P14.0 programming software and reprogram the Engine Control Module.

Quality Monitoring M60 Oxygen Sensors

Model:
BMW E34 and BMW E38 with M60 B40 engines produced from September 1994 to August 1995
Complaint:
The oxygen sensors of the listed vehicles need to be replaced with new sensors as a quality monitoring gauge. The old sensors should be returned to the Warranty Parts return Centre with a copy of any DME fault codes if present.
Remedy:
Utilize the ‘Service Menu’ of the Dealer Communication System, enter the chassis number of the vehicle involved and based upon the response of the system either proceed with corrective action, or take no action at all. If action is necessary then:

-Obtain customer permission and signature to authorize the extraction of both left and right oxygen sensors.
-Read and print out DME faults.

Test/hex code printout procedure:
Select ‘3 service functions’ and right arrow button.
Select ‘1 test code’ and right arrow button.
Select ‘test code R’
Select print ‘diagnosis report’

-Ignore any oxygen sensor fault codes if present.
-Clear all fault codes stored in the DME
-Replace both oxygen sensors referring to the repair manual group 11 section.

Oxygen Sensor Wiring Harness Voluntary Recall Campaign No. 98E A02

Model:
BMW E36 with M42 engine (manual transmission only)
Complaint:
A voluntary campaign from BMW in North America is recalling the oxygen sensor wiring harness of the above vehicles. The oxygen sensor harness may have been routed incorrectly during production. One possible solution could be the oxygen sensor harness has been accidentally secured with clips to the exhaust heat shield and/or to a bracket on the transmission housing. The oxygen sensor harness could stretch and eventually break with the movement between the vehicle body, transmission and exhaust system causing the check engine light to illuminate and the fault code 70 – oxygen sensor disconnected to set in the DME.
Remedy:
Utilize the ‘Service Menu’ of the Dealer Communication System, enter the chassis number of the vehicle involved and based upon the response of the system either proceed with corrective action, or take no action at all. If action is necessary then:

-Read and print out the DME faults.
-Troubleshoot and repair DME fault codes other than fault code 70 using the DIS tester instructions as necessary.
-Check the oxygen sensor harness for hold down clips or any signs (crimped or pinched areas in the sheathing) where a clip or other hold down device may have been installed in the past.
-Remove all clips and other oxygen sensor wiring harness hold down devices from the exhaust heat shield, transmission bracket.
-If installed, bend the transmission bracket using a pair of up over the bolt head.
- The oxygen sensor must only be replaced if the oxygen sensor harness had any fastener holding it in place, or the oxygen sensor shows any signs of it being fastened previously, or Fault Code 70 is stored in the DME.