CHECK HARNESS BETWEEN ECM AND DATA LINK CONNECTOR.

Measure the resistance between data link connector and chassis ground.

Connector & terminal

(B40) No. 7 — Chassis ground:

QUESTION

Is the resistance 1 MΩ or more?

Yes No

Repair the poor contact of the ECM or data link connector.

Repair the ground short circuit of harness between ECM and data link connector.