CHECK ECM GROUND HARNESS.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B135) No. 3 (+) — Chassis ground (−):

(B135) No. 4 (+) — Chassis ground (−):

QUESTION

Is the voltage less than 1 V?

Yes No

Repair the poor contact of ECM connector. Replace the ECM if defective.

Repair the following item.

Further tighten the engine ground terminal.

Poor contact in ECM connector

Poor contact of coupling connector