Circuit/System Testing
- Measure the voltage at the battery terminals and compare it with the Ignition 1 Signal parameter in the ECM data list. Verify that battery and Ignition 1 signal readings do not differ more than 1.0 volts.
- If greater than 1.0 volts test the Ignition 1, ground circuits of the ECM for high resistance or replace the ECM.
- Refer to Charging System Test .