My right rear door courtesy light has two wires- a solid red and a black w/ white stripe. What puzzles me is that both wires have voltage across them when the key is turned to the left or right. To me the red is the feed and black would go to the door jamb switch. I currently do not have a bulb in the socket- there never was one in place. None of the courtesy lights in the door pull handles worked in any of the doors when I bought it. I got the right front fixed after splicing the red and blk w/white wires which were severed in the door jamb. The right front now comes on when I open either of the front doors, telling me the front door jamb switches are good. I still have to splice those two wires in the left front door jamb which are severed, but not shorted. I have a '63 Sedan DeVille, 6339. The schematics in the manual are somewhat helpful, but the color coding doesn't match with what I have( pages 12-93, 16-104, 16-118 ). I should state that my wiring is still encased in the cloth tape so I know it's stock, also, the wires are not damaged in the rear right door jamb.Why do I have power (12V) on BOTH the red and black? I'm not putting a bulb in there until I fix it right. This is driving me up the wall.
Robert- thanks- I will be sure to check in that location.
Andy, everything you need to know is already at hand. If you ground the black wire with a bulb in place, the bulb lights. So you have no ground at the jamb switches or the seat switch. You should start by repairing what you know is broken (seat switch and left front door), and then check out your jamb switches on the back doors. Jason already made a nice video about here:
JASON'S DOOR JAMB VIDEO
On most Cadillacs of the Sixties, the grounds would be spliced at the door jamb switches. You should take one out and test for continuity between there and the black wire. If there isn't any, you know you have a broken wire, start digging. If everything lights up when you ground the wires to the switch, then you're done, clean or replace the switch.
Thanks Mark- already started doing just that and I'll deal with the other issue later. Just for the heck of it, I checked the rear left side for comparison. It's bulb was good,yet wouldn't illuminate. When I took the bulb out, so as to see what I had for voltage it checked out good- only on one side of the bulb socket. Here's the kicker... while the bulb was pulled out on the left rear, I checked the right rear- the voltage on the black/white wire was gone. So when the left rear bulb is in place, that's when 12V will show up on the blk/white wire on the right rear bulb holder. This is gonna be a fun fix. And thanks for the heads up on the video.
The voltage you see on the ground side when the circuit isn't on is normal; the voltage on the right side is "leeching" through the filament of the bulb on the left side, because they are all connected. This is very good news, it means there is an unbroken circuit on the ground side, and all you need to fix is the final ground points. Getting there. If you install the bulb on either side and ground the black wire on the other side do they light up?
Thanks for everyone’s input. It all helped. My problem ended up being caused by a loss of ground on both rear door jamb switches. The car had seen a lot of gravel roads prior to my purchase and acquired road dust in the switches and within the doors themselves. Cleaned the switches with brake cleaner followed with electronic spray. They work fine now. Am including pics of the rats nest of broken wires found in the front door jamb. Someone had tried fixing the electric seat wiring, but the broken window wires were still encased in the cloth tape.