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

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

2) Turn the ignition switch to ON.

3) Measure the voltage of harness between ECM connector and chassis ground.

Connector & terminal

(B134) No. 18 (+) — Chassis ground (−):

(B134) No. 28 (+) — Chassis ground (−):

QUESTION

Is the voltage 8 V or more?

Yes No

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

Replace the front oxygen (A/F) sensor.