Electrical problem

[scott hasko]

I'm not too good with hunting down electrical problems so I thought I'd tap into the experience represented on this board. I just replaced a main under-dash wiring harness on a friend's 1966 roadster. Everything was working OK with the original harness, but there was some damage and the fuse block was broken, so he wanted it replaced. The installation went fine but during testing the operation of all of the electrical functions we discovered that the courtesy lights remain on. We removed and inspected the door jamb switches but that's as far as we have gotten. I plan on revisiting the problem this week, and thought I would ask about where to begin troubleshooting this gremlin.
-Scott

[William C.]

Re: Electrical problem

Have you checked the position of the light switch? It will turn the ctsy lamps on when rotated fully counter-clockwise. When troupblshooting, you are looking for a problem in the ground circuit. The lamps have power to them at all times, and the switches provide a ground path.

[scott hasko]

Re: Electrical problem

Thanks Bill. Yes, first thing I checked was the light switch and dimmer. I will take a look at the grounds. Wondering if the harness ground clip (to the cluster) could have fallen off, and if that would cause the problem.
-Scott

[Stephen L.]

Re: Electrical problem

The wire that you will be tracing is a #18 white wire. Remove it from the door switches (Isolate the wire end from ground) and from the headlamp switch. If the lights remain on then you have a problem in the harness (pinched wire etc.) If the lights go out, then connect the switches, one at a time, until the light problem returns. Also check that a courtesy lamp socket is not grounded and that you have the correct bulbs (2POLE) in all 3 locations.