Over head lights suck

[bigblack'74]

For 1984 Wag.....ok courtesy lights work with all door sensors, with the cargo switch and the light switch turned on. all door sensors have been tested and isolated to rule them out as a problem. the problem is that the over head lights have constant power to both wires on each unit when all doors are closed and all switches off. when you either open a door, or switch the lights on, both wires lose all power. another point to note is when the doors are closed and switches are off the map lights will work only one at a time.( not both at the same time, or they will both shut off) when you open the door those maps lights go out and then the filament in the overhead lights turns faint red. so it so it is like somrwhere there is backfeed or else there is some type of cross over...I am Extremely exprienced with 12v ground side switching but this crazy, it doesnt even make sense


As i understand this system there is one constant wire (brown) that is hot going to the over head light, and there is the ground wire (black). the power is always on so that the constant lights, ie: map lights and vanity light will take the 12v thru thier respective switches and then ground out to the body, where are the over headlight used the 12v thru it then the ground is attained by either opening the door, switching the cargo switch, or switching the interior lights on this ground is conected thru the black wire back to those switching devices.... so someone tell me why the heat is in both wires????

[letank]

i think that you nailed it, you have a short on the overhead creating a feedback... disco one overhead bulb at a time, either bulb or socket base

and i agree the system is insane

[bigblack'74]

another thing to note, is I tested the wires at the connector on the floor before they go out accross the floorboard, up the pillar and into the overheadlites. what I found was that the brown wire(suposedly constanT) was hot all the time at the connector, no matter what you did with the door switches or the other interior light switches. the black wire on the other hand would turn off when the door were opened or you turned on the interior lights, just like it does at the overhead light. The brown wire also turns on and off with the black wire at the over head light. So my guess is, since the brown wire ( constant heat) is ok at the spade conector on the floor, but not ok at the over head light, the brown wire is somehow contacting the black wire somewhere after the spade connector but before the overhead light. this is how come the black wire, which is a ground, is backfeeding to the brown wire, or visaversa......if anyone can shed anymore light on the subject that would be great...i am racking my brain to figure it out..I know it is trivial, but it is the only thing that doesnt work right so it makes it that much more annoying... thanks

[letank]

the backtracking is called finding the path of least resistance.... of course in your case this path, has a strong resistance for the voltage, but still manage to go thru.

this is the same issue w weak blinkers or dash lites that dim when you put the blinkers on. I had the problem w front right blinker, i was ready to rewire, but after i cut off the wire.... realized that i had a spare blinker assy. so i connected the newer/better shape blinker assy. and the blinker was bright, so was the parking lights and so was the blinker indicator

do a search for "ground" or the electrician specialist "gilbeau" or "junkyardgenius" they have covered this topic

[bigblack'74]

black and brown wires busted and touching on the floorboard under carpet, cut out the bad wires and overhead lights work now...thanks