CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from front oxygen (A/F) sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between ECM and chassis ground.

Connector & terminal

(B135) No. 9 (+) — Chassis ground (−):

(B135) No. 8 (+) — Chassis ground (−):

QUESTION

Is the voltage 8 V or more?

Yes No

Repair the short circuit to power in the harness between the ECM and front oxygen (A/F) sensor connector.

Replace the front oxygen (A/F) sensor.