CHECK HARNESS BETWEEN ECM AND REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between rear oxygen sensor connector and chassis ground.

Connector & terminal

(E22) No. 4 (+) — Chassis ground (−):

QUESTION
Is the voltage 0.2 — 0.5 V?
Yes	No
	Repair the harness and connector. NOTE: In this case, repair the following item: • Open circuit in harness between ECM and rear oxygen sensor • Poor contact of ECM connector • Poor contact of coupling connector