Wiring Diagram:

Fig 1: Wiring Diagram - Control Module Performance

Courtesy of SAAB-SCANIA OF AMERICA, INC.

CHECK INPUT VOLTAGE OF ECM

Turn the ignition switch to ON.

Measure the voltage between ECM connector and ground.

Connector & terminal

(B135) No. 5 (+) - Chassis ground (- ):

(B135) No. 6 (+) - Chassis ground (- ):

Is the measured value 10 - 13 V?

YES. Go to next step.

Repair the open circuit or ground short of power supply circuit.

CHECK INPUT VOLTAGE OF ECM

Start the engine.

Measure the voltage between ECM connector and ground.

Connector & terminal

(B135) No. 5 (+) - Chassis ground (- ):

(B135) No. 6 (+) - Chassis ground (- ):

Is the measured value 13 - 15 V?

YES. Go to next step.

Repair the open circuit or ground short of power supply circuit.

CHECK GROUND HARNESS OF ECM

Measure the voltage between ECM connector and ground.

Connector & terminal

(B137) No. 7 (+) - Chassis ground (- ):

Is the measured value less than 1 V?

YES

Repair poor contact of ECM connector. If poor contact occur, replace the ECM.

Retighten the engine ground terminal.