Brake light issues

[nightman61]

Good day everyone, Has anyone had an issue with brake lights? car: 1980 Dodge Diplomat, 2dr. 46K miles. Was driving the other day, had a friend behind me. When I got home, was told, No brake lights working. Checked fuse, blown. Replaced fuse, worked for a while, blew again. Car has also blown fuses for door locks. replaced that also. One of the previous owners had installed 3rd brake light. I have unplugged it, thinking smart box with it, may have gone bad. Blinkers are being affected also. Anyone have an issue like this? Fix it, works fine for a couple of days, then blows fuse again. I replaced brake light switch, after checking it and found original one bad. Interior lights are working, which is tied to same fuse as stop lights.

 

[Camtron]

Sounds like a wire/terminal connection is intermittently grounding.

 

[nightman61]

Sounds like a wire/terminal connection is intermittently grounding.

I read an older post where someone was having a similar issue. His 3rd brake light was working, but not regular ones. Someone said routing on wiring runs through turn signal switch. I disconnect aftermarket 3rd brake light, thinking maybe little brain box on it went bad, but blinkers are acting up also, blinking fast, but bulbs all work. Replacing flasher, pretty bad, can't get those local at parts stores because computers don't show, and ordered turn signal switch. Original ones are still in car, so can't complain. When it cools down from 1000 degrees outside, I'll do some more digging, but pretty sure this may solve issues. I will update here just for record, In case someone else has the issue.

 

[AMC Diplomat]

Sounds like you need wiring diagrams for 1980. I only have 77, 87 and 88 for service manuals. Maybe someone here has 1980.

 

[nightman61]

Sounds like you need wiring diagrams for 1980. I only have 77, 87 and 88 for service manuals. Maybe someone here has 1980.

Have the wiring diagram for system, located in Haynes 1971-1989 RWD repair manual. It does show some of the wiring. Checking diagrams, I see wiring is shared back to turn signal switch. Turn signal switch works like it should, but as with what appears to be simple things, who knows. Wondering if maybe the Flashers could be part of the issue also. Little more research, I have not seen any issues with wiring, such as grounding (open wire), anywhere. Yes, electrical issues are difficult, if mother nature would just give me a break from 100 plus temps, this would go easier.

 

[AMC Diplomat]

Have the wiring diagram for system, located in Haynes 1971-1989 RWD repair manual. It does show some of the wiring. Checking diagrams, I see wiring is shared back to turn signal switch. Turn signal switch works like it should, but as with what appears to be simple things, who knows. Wondering if maybe the Flashers could be part of the issue also. Little more research, I have not seen any issues with wiring, such as grounding (open wire), anywhere. Yes, electrical issues are difficult, if mother nature would just give me a break from 100 plus temps, this would go easier.

There are slight differences every couple years with the wiring.

Autozone carries the flashers, that's where i got mine

 

[nightman61]

Update: Finally got the car torn apart. Got down to the turn signal, and getting to the right plug for the turn signal switch. Saw a little melting on one end. When I finally got it apart, found 3 wires had melted together. Not sure how, and not sure which ones, yet. I am going to look at wiring diagram to identify them. This would explain the blown fuses over a couple of weeks.

 

[Camtron]

Have you checked OHMS and continuity across the pins on the factory turn signal switch? If you have anything disassembled already, may as well pin the switch out and see if it’s actually good or bad if they’re not readily available.

 

[toolmanmike]

Have the wiring diagram for system, located in Haynes 1971-1989 RWD repair manual. It does show some of the wiring. Checking diagrams, I see wiring is shared back to turn signal switch. Turn signal switch works like it should, but as with what appears to be simple things, who knows. Wondering if maybe the Flashers could be part of the issue also. Little more research, I have not seen any issues with wiring, such as grounding (open wire), anywhere. Yes, electrical issues are difficult, if mother nature would just give me a break from 100 plus temps, this would go easier.

Look on Mymopar.com for factory wiring diagrams or buy a factory service manual. Haynes are bottom shelf manuals. Just saying.

 

[toolmanmike]

Lots of turn signal switch issues nowdays. They are all almost 50 years old and worn out. Sad to say but most of the aftermarket repops don't work out of the box. A NOS one is the best bet.