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MALFUNCTION INDICATOR LIGHT DOES NOT COME ON

MALFUNCTION INDICATOR LIGHT DOES NOT COME ON

DIAGNOSIS:

The malfunction indicator light circuit is shorted.

TROUBLE SYMPTOM:

When the ignition switch is turned to ON (engine OFF), malfunction indicator light does not come on.

WIRING DIAGRAM:


CHECK OUTPUT SIGNAL FROM ECM.

Turn the ignition switch to ON.

Measure the voltage between ECM connector and chassis ground.

Connector & terminal

(B84) No. 15 (+) — Chassis ground (−):

Is the voltage less than 1 V?

Yes


No


CHECK POOR CONTACT.

Does the malfunction indicator light come on when shaking or pulling ECM connector and harness?

Yes

Repair the poor contact in ECM connector.


No


CHECK ECM CONNECTOR.

Is the ECM connector correctly connected?

Yes

Replace the ECM.


No

Repair the connection of ECM connector.


CHECK HARNESS BETWEEN COMBINATION METER AND ECM CONNECTOR.

Turn the ignition switch to OFF.

Remove the combination meter.

Disconnect the connector from ECM and combination meter.

Measure the resistance of harness between ECM and combination meter connector.

Connector & terminal

(B84) No. 15 — (i11) No. 6:

Is the resistance less than 1 Ω?

Yes


No

Repair the harness and connector.

Note

In this case, repair the following:

Open circuit in harness between ECM and combination meter connector

Poor contact in coupling connector



CHECK POOR CONTACT.

Check poor contact in combination meter connector.

Is there poor contact in combination meter connector?

Yes

Repair the poor contact in combination meter connector.


No


CHECK HARNESS BETWEEN COMBINATION METER AND IGNITION SWITCH CONNECTOR.

Turn the ignition switch to ON.

Measure the voltage between combination meter connector and chassis ground.

Connector & terminal

(i12) No. 7 (+) — Chassis ground (−):

Is the voltage more than 10 V?

Yes

Replace the combination meter circuit board.


No

Check the following and repair if necessary.

Note
Blown out fuse (No. 13)

Open or short circuit in harness between fuse (No. 13) and battery terminal

Poor contact in ignition switch connector