## Diesel Engine Management System

#### DTC Troubleshooting (cont'd)

11-80

1. Measure voltage between the ECM A connector terminals No. 5 and No. 2.

Is there battery voltage?

YES – Go to step 16.

NO – Repair open in the wire between the main relay and the ECM. If a problem is not found, replace the main relay.

1. Go to the Starting/Charging System.

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

NOTICE

The battery power supply short circuit to 5 V power supply damages the ECM.

a a a