Electrical
How to chase an intermittent electrical fault
Intermittents are found with live data and a wiggle test, not with parts. Make the fault happen while you are watching it.
The answer
Method
- Record the inactive fault codes and their counts before you touch anything.
- Put the suspect circuit on live data and wiggle each connector and harness section while watching for a dropout.
- Inspect connector pins for green corrosion, spread terminals and pushed-back pins.
- Check every ground stud in that circuit — clean metal, correct torque, no paint under the ring terminal.
- Flex the harness where it crosses a frame rail or a moving component. That is where chafe happens.
Document it
Note the fault count and the mileage each time. If the count stops rising after a repair, you actually fixed it — that is your proof.