Tips for Tracking Down Wiring Issue that Causes Vehicle Lights to Stop Working

Question:

I have a 78 skylark and recently my inside and outside lights no longer work but turn signals still work fine. Im thinking its a ground but have no idea where to start or look

asked by: Aaron W

Expert Reply:

I'd first test to see if power is making it to the wiring of the lights that aren't working. If so, then like you suspected it's a ground issue. If not, then you'll have to find the power issue. On a vehicle as old as yours it really could be a lot of things but first check fuses and use a circuit tester like part # PTW2993 to find out where the circuit is active and if possible trace it back to the lights to see where it stops. This will narrow down finding the issue.

A coworker of mine saw this and told me to add this, "If it has the brights switch on the floor then it could be that. I had a 78 GM product that did the same thing and it was because of that switch."

expert reply by: Jameson C