Charging System Indicator Circuit Troubleshooting
Check for continuity between ECM connector terminal B42 and body ground.
Is there continuity?
YES
-
Update the ECM if it does not have the latest software,
or
substitute a known-good ECM,
then recheck. If the symptom/indication goes away with a known-good ECM,
replace the original ECM.
■
NO
-
Repair open in the wire between the alternator and the ECM.■