Instrument Cluster - False Check Display Light
88BMW04GROUP 62 Instruments
Bulletin Number 62 05 88 (1689) Page 1 of 5
Montvale, NJ July 1988 Technical Dept.
SUBJECT: Active Check Control
MODELS M3
Customer
Complaint: The "CHECK" display light in the instrument cluster continues to flash after stepping on the brake pedal and no faults are displayed on the Active Check Control.
The button on the Active Check Control must be pressed to turn off the light.
Situation: Due to the construction of the oil pan found on the S14 engine, it was not possible to mount an oil level sensor in the proper position to monitor the oil level.
A basic Active Check Control module is used with the ENGINE OIL inscription and LED removed. However, the engine oil level monitoring circuitry is retained.
For this reason the Active Check Control module must be given a simulated proper oil level signal. If this signal is not supplied the "CHECK" display will be illuminated as mentioned previously.
Different methods of simulating this signal have been used in production. These are also shown on the attached schematics.
Method A: An oil level sensor was placed on the bottom of the oil pan in an "upside-down" position thereby giving the Active Check Control module a constant "full" signal.
Method B: An adaptor harness P/N 12 61 1 311 511 was installed in place of the oil level sensor. It consists of a ground wire and a 1000 ohm resistor.
Method C: A 1000 ohm resistor was placed across pins 2 and 10 of C101 on the engine harness side. Pin 2 is also grounded via G103. The resistor is found under the rubber boot on the connector.
Troubleshooting
Procedure: Perform the following measurements:
Use the attached schematics to determine location of fault.
If it is determined that the oil level sensor is defective, do not replace. Install adaptor harness P/N 12 61 1 311 511. Cut off connector on oil level sensor.
6216-2 ACTIVE CHECK CONTROL