## Diesel Engine Management System

#### OBD System Troubleshooting (cont'd)

11-147

No Malfunction Indicator Lamp (MIL)

1. Check the ''On Board Diagnostic (OBD) System Check''.

Was the OBD System Check performed?

YES – Go to step 2.

NO – Go to OBD System Check.

1. Check for the following conditions:

- The meter fuse
- The ignition feed fuse

Is the fuse OK?

YES – Go to step 3.

NO – Replace the fuse.

1. Turn the ignition switch OFF.

1. Disconnect ECM A connector.

1. Connect the ECM A connector terminal No. 15 and body ground with a jumper wire.

1. Turn the ignition switch ON (II).

Is the MIL turn ON?

YES – Substitute a known-good ECM and recheck. If symptom/indication goes away, replace the original ECM.

NO – Go to step 7.

1. Turn the ignition switch OFF.

1. Disconnect meter connector.

1. Check for an open in the wire between the ECM A connector terminal No. 15 and meter connector terminal No. 18.

Is a problem found?

YES – Repair an open in the wire.

NO – Go to step 10.

1. Connect the meter connector terminal No. 8 and body ground with a test light.

METER CONNECTOR 22P CONNECTOR

Wire side of female terminals

1. Turn the ignition switch ON (II).

Is the test light turn ON?

YES – Go to step 12.

NO – Repair an open in the instrument cluster ignition feed circuit.

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