Medium and Heavy Trucks
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Hi my name is***** will be glad to try to help. What year chassis is this?
6891 4 CHM power feedVBAT1 — low voltageThe output circuits that are powered by VBAT1 will all beinoperative. Other fault codes may be present, but troubleshootfor this first. The fuse in the main PDM powering this circuit maybe open. The root cause could be excessive loads on anoutput, or a short to ground in the VBAT1 supply to the CHM
Test all fuses for power on both sides with the key on. Replace any with power on only one side. Thoroughly inspect the wiring harness and connector pins for damage and corrosion and the lighting circuit for faulty bulbs, grounds, etc. Let me know.