With - BMW DIAGNOSTIC SYSTEM

SYSTEM DIAGNOSIS

Caution: Remove or install the Motronic Control Unit only when the Ignition Switch is OFF. Probe the Control Unit electronic connections only with the Universal Adapter connected.

- Check that the Starter System is in perfect condition (battery charged, starter and ignition interlock are good).
- Check that the ground connections between the body and the engine wire harness are good.
- Check that engine is within specifications mechanically (timing, compression, etc.).
- Connect the Service Tester and perform the Diagnostic Check.
- If a DME Fault Code is present, print out the DME Codes and continue.
- if a Momentary (intermittent) Fault Code is displayed, the normal diagnosis cannot be followed. Use the following special procedure.

a. Visually inspect all related wiring.
b. Print out conditions recorded by the Service Tester (engine speed, engine temperature, etc.).
c. Try to reproduce the conditions recorded by running the engine or driving the vehicle.

- Use the Service Tester to read the Fault Codes again.
- If the Fault Code is now shown as Actual, go to the Symptom Table.
- If the Fault Code is again listed as Momentary, check the wires. Replace the component related to that Fault Code.
- If the Fault Code is not present, but customer reports a problem, replace the component related to that Fault Code.
- If any of the following DME Fault Codes are present, follow the diagnosis given on the Tester Display.
- DME Fault Codes: 01, 04, 22, 29, 37, 44, 45, 47, 52, and 53.
- If any other DME Fault code is present, refer to the Symptom Table.