3rd brake light randomly comes on

[Mudgopher]

I got an aftermarket LED 3rd brake light for my 98 Silverado. I threw the old original away as it looked like garbage. Now after my truck sits for a minute or so the 3rd brake light randomly comes on. It will stay on until I open a door, at which point it goes out. But it will again come back on if it sits for a bit. People are constantly coming up to me telling me my lights are on.

I thought at first it might be due to a switch in the door, but it does this with both doors. I guess both switches could be bad, but it's odd this just started when I got the LED brake light. Also the LED brake light doesn't have a good seal and water can get through the edges. I'm not sure if that has anything to do with it. I need to get a different one or silicone this one up. Lots of variables here really, but if anyone else has had a similar experience maybe they can narrow it down a bit for me.

Thanks!

 

[Mudgopher]

Also I just installed an aftermarket stereo head unit about a month ago. Everything worked great up until two days ago when I started the truck up and the stereo didn't come on. Took it a part today, the fuse on the stereo looks good, fuse on the fuse panel looks good, wiring looks good; still not working. Not sure what is up, but I can't find my crappy cheapo multimeter so I'm kind of stuck at the moment.

 

[thunderstruck]

Not going to be much help since I'm on mobile and don't have a wiring diagram available, but does the light go out when you open the doors and have the dome light override button pushed in (dome lights off)?


Sent from my Nintendo 64

 

[Mudgopher]

I believe that is what it typically does. I open the door and it goes out. After shutting the door for a while it'll come back on. I have the dash all a part working on the stereo and it's dark out now so I can't make sure at the moment.

 

[1sickcrewcab]

When I installed my led 3rd light it didn't work when I plugged in the harness together. It was acting strange as well. So I cut harness plug off 3rd light and cut 2 wires off truck harness and just connected those 2 wires and now the led brake light works. This is my 2nd 3rd led brake light. First one fit light crap and would leak until I tried tighting the screws and just broke light. 2nd light I got was a lot better and hasn't leaked. Think I connected the yellow and black wires from truck, you just to figure out what wires from your brake light are going to power it up. Heres my light

You must be registered for see images attach

You must be registered for see images attach

 

[IOWNJUNK]

I feel your pain. Only the right side bed lights work and the 3rd brake lights only worked one time when I was following my daughter while she drove.

 

[Mudgopher]

I guess I'll just have to fiddle with the wiring. The stereo issue is the most annoying. Not having any music while driving is pretty boring...just in time for Thanksgiving commutes too .

 

[pewterz71]

Not going to be much help since I'm on mobile and don't have a wiring diagram available, but does the light go out when you open the doors and have the dome light override button pushed in (dome lights off)?


Sent from my Nintendo 64

hey i just got an led 3rd brake light and hooked it up and it did the exact same thing that the first guys did. when the dome lights were on the brake light would be off but as soon as the dome light turns off the brake light turns on. (with override on and off). as far as the functionality of the light goes, it works great and all lights light up, but when the dome light turns off the light stays on with the truck on or off. does anyone have any idea whats going on?

 

[pewterz71]

i figured out this issue, cut or remove the yellow wire from your new light. it takes it away from the hot source in your truck and works with your brakes and cab light just fine

 

[Buddy_flowers]

i figured out this issue, cut or remove the yellow wire from your new light. it takes it away from the hot source in your truck and works with your brakes and cab light just fine

You are my favorite person on earth. Like ever.