CHECK INPUT SIGNAL OF ECM.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM and chassis ground.

Connector & terminal

Euro 4 model

(B137) No. 17 (+) — Chassis ground (−):

Euro 5 model

(B134) No. 9 (+) — Chassis ground (−):

QUESTION
Is the voltage 2 V or more?
Yes	No
Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.	Repair the poor contact of ECM connector.