This is a general information section and by no means can be used to diagnose your car. ProgRama Inc is not responsible for any damages as a result of the use of this procedure. ProgRama recommends always that a professionally trained technician evaluate car problems.

 

BMW ECU - Car breaks down, intermittent start and no cylinder spark.
It is important to identify whether or not you have the old 35 or 55 PIN computer or the newer 88 PIN computer.

For the 35 or 55 pin computer, follow these steps to see if the problem is the ECU:

1. Check if the fuel pump and injectors are working properly.
2. If all is well, check for very low ignition pulse.
3. If all is well, check all LT and HT coils for defect and exchange if necessary.
4. If all is well, you may have a bad ECU.

For the 88 pin computer:

1. Check coil pack for splits or burn marks. If the coil pack is bad, the ECU WILL fail.
2. Check affected cylinders for severely reduced coil kV. Can be tested using an automotive scope.
3. If all is well, you may have a bad ECU.