DME System 2

Injection Electronics (Motronic Control Unit II). Wiring Diagram:

1. With the ignition switch in the OFF position, disconnect the coolant temperature sensor connector X1622 (located at the rear of the right cylinder bank).

Coolant Temperature Sensor Location:

Fig. 25 Coolant Temperature Sensor Location:

2. Turn the ignition switch to the run (ON) position, and make the following voltage measurements at connector X1622 (female side).

^ Brown/red wire (terminal 3) and ground = approx. 5 volts If not check wire to terminal 45 of the DME control unit X1601 for an open or short to voltage or ground. If wire is OK, the DME control unit is defective.
^ Brown/red (terminal 3) and brown wire (terminal 2) = approx. 5 volts If not check wire to ground for an open.

^ If all voltages are correct continue with step 3.

3. With the ignition switch in the OFF position, clear the DME control unit memory by disconnecting the DME control unit harness connector X1601. Reconnect the control unit harness connector.
4. Replace the coolant temperature sensor.
5. Start the engine and warm it up to normal operating temperature, varying the load conditions.

^ If the check engine light remains off, retain the new coolant temperature sensor. End of test.

^ If the "Check Engine" light illuminates repeat the "SELF-DIAGNOSTIC PROCEDURES". If a code 2223 is present the DME control unit is defective.