i know this topic has been covered a few times, and I have searched for an answer, but I’m still not sure what’s going on. So it’s a 63 coupe with a bench seat and I had to replace the door jam switches ,with the newer style that’s just the two wires  and added a ground to the body .

But , when I do that , (add the third body ground ) the front  courtesy lights and the map light stay on with the door closed. The door jam switch just turns the rear courtesy lights on/off.

If I take off the added ground off  and the door is closed, the map light turns the front lights on/off.

the rear switch on the back of the seat , turns the rear lights on/ off.

With the door open , the switch doesn’t do anything, but the map light switch will turn all the lights on/off.

I thought maybe it was the headlight switch dimmer knob , but that seem to be working fine, it turns the lights on/off  

Sorry if that sounds confusing, But what am I overlooking?

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Which body style coupe? Series 62 or Coupe de Ville? How many wires originally to switch? 1,2 or 3? 

Its the 6357 body style , I believe that’s the coupe De Ville , and the original switches were 3 wires 

There are many combinations of courtesy lights and there is no one answer that fits all, however, some basic info can help figure out courtesy light issues:
The Coupe and Front Sedan doors may have 1, 2 or 3 contacts due to difference is coupes vs sedans and Series 62 vs de Villes/Fleetwoods

For example:
- a 1963/64 Coupe de Ville has 3 contact switches in the doors since it triggers 3 lights: dash courtesy/map, door courtesy, rear passenger. 

- a 1963/64 Sedan de Ville has 3 contact switches in the doors since it triggers 3 lights: dash courtesy/map, door courtesy but does not trigger the rear passenger courtesy light, since it is triggered by the rear door pin switches.

- Since the Series 62 body styles (except 1963 convertible 6267) does not have the door panel courtesy lights then you subtract one contact giving 2 for Coupes and 1 for Sedan for those body styles.

Now for the tricky part. When you use a door jamb switch with an override switch such as the 1963 center dash map light, or the rear of front seat rear passenger courtesy light switch, if you splice one of the other "to ground" wires into the same circuit with these override switches you will also take them to ground when you turn that light on via the override switch. The bottom line is you want to keep the courtesy light switch circuits with an override switch (i.e. 63 map light, 63/64 rear passenger switch) on an isolated circuit and not spliced into with the other wires.

Finally, I have never used an aftermarket courtesy light switch where you have to run a separate wire to ground. The switches push into the body opening metal where you have a ground and all the after market switches I have used simply ground through the switch body to car body where they push into the hole.

One final note: Determining which wire controls which light circuits is easy. Just pop the switch out (if connected), removed the wires from the switch and touch the male connector on the end of the black wire to the metal rim of the switch hole. These simply take circuits to ground and is an easy way to ID the lights each wire controls. If it is a 63 and is the map circuit, connect it to a separate switch contact; if the back of seat switch, same thing.

Hope that helps.

Yes I think that helps , thank you.  I have a idea of what’s maybe wrong, I’ll try it when I get home tonight and see what happens . 

On the new door jamb switches, one of the wires is for an external ground.  

Here’s a diagram of what I did , the blue box is how I wired it for the 2 terminal switch ,I’m guessing I wired it wrong....

I am unfamiliar with these newer after market switches where you have to use one connector to make ground since the factory light switches and all the aftermarket types I have used simply ground through the body.  For such a switch one contact needs to go to ground and not be spliced with anything else, and the other "feed" contacts need to go to the other connector. Again, the problem is splicing the map light feed and/or the back of switch feed to any other wire is going to mean when you turn that specific switch you, you are taking the other wire you have spliced to it to ground and it will also light up.

I figured it out last night, I had I wired wrong. My mistake was not connecting the red wire to the two black in one terminal,. They work now , not completely like it was originally , but it works . Thanks for the help and info.

Main thing is to get some light in there, even if extra lights come on with auxiliary light (map/courtesy) turned on.  With the new wiring, with doors closed and headlight courtesy light switch in off position, do other lights come on when you turn the map light on, or the back of seat light? 

Yes, the map light switch and the seat switch turn all the lights on instead of being independent, but that’s fine, I can live with that for now . 

Yup, they take anything spliced in with those wires to ground and will come on. For years I had seen aftermarket switches grounded via the switch body with 2 contacts, and they were 2 independent switch contacts. If you can at least find one of those, you could isolate the dash map light to one of the 2 contacts. 



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