brake lights not working?

Hello,

There is a stop light inhibit control relay (check the wiring diagrams) that goes out, here is a wiring diagram that will show you where it is and a guide on how to test it.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Here are the relay locations (below). Please run this test and get back to us so we can continue helping you.

My brake lights stopped working, I checked the fuse, and replaced it, but they still dont work. All other lights are fine. What might be done about this?

Is the "cyclops" working? High mount brake light? If no then check the stop light switch on the brake pedal arm, if yes, check the multifunction switch(blinker).

I had the exact same problem. If you go to an auto part store and ask for a brake light switch they will have one. Its about 12 bucks. Take to a dealer ship and ask them to put it in. I did and they done it for free. Good luck

You need to test for power and ground arriving before concluding that. Here is a guide

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Please run down this guide and report back.

does it have a "squeezer dealee" connecting the cable to the clamp? clean it too! sometimes you can flip, the top of the squeezer over, and get more pressure on the cable

as for the rear lighting, might not be burned out, lots of problems with the "twisty light holders"---on the holder, sorta bend the brass contact out some more...a little sanding on the circle, of the tail light side, smear on a little "dielectric grease".....presto, your fixed.....might as well do 'em all.....it's only a matter of time!


THE MEDIC

Electrical problem
2000 Jeep Grand Cherokee V8 All Wheel Drive Automatic 158455 miles

Brake light works fine when brakes applied. Tail light works fine when turned on. With lights on and apply brakes, tail light goes out and no brake light. Only on left side, right side works well and middle lbrake light on top of lift gate works fine.

this is a grounding issue, you will want to inspect ground wiring at both taillight assemblies to ensure wiring is connected properly and not dirty or damaged.

I've been told that my brake light doesn't work with the headlights on because of a broken ground wire. How do I repair the ground wire?

You find where it's broken first. That determines how it's repaired. You might install a new terminal, splice a cut wire, or if it's severely corroded, run a new wire. If the wire is corroded off a socket, replacing the entire socket is usually easiest. Some vehicles use printed circuits on the lamp housings and those can develop a hairline crack. Some can be repaired. Some have to be replaced.

no brakes lights.

Could you provide some hints or observations to analyze? Have you checked the fuses? Brake light switch? Do the other lights work correctly? Do you have cruise control? If so, does it work and does it cancel when you tap the brake pedal?

third brake light not working the other ones are ok. plugged in one that works it did not light. is there a separate fuse from the other lights? could there be a broken wire and where?

Have you checked to see if there is power to the light socket? There is no separate fuse, so if there is no power to the socket, there must be a broken wire. The only thing you can do is trace the power supply to locate the break.

There shouldnt be a seperate fuse if there is a broken wire wouldnt know where it was without looking.Also what are missing at the light the power or ground side of it?

The two bottom brake lights work as long as the lights are not on. When the parking lights are on, the two large lights go completely dark. I have checked all the fuses and I have replaced all the bulbs in all three lights. There are a couple of other electrical quirks as well. The tire monitors are off and the seatbelt light stays on all the time. All I really care about is the brake lights.

Please help. Initially, had no rear lights at all. Replaced brake light switch and fixed tail lights.
Fuse was blowing immediately when I put in new fuse. Now, I have tail lights, blinkers and reverse lights, but all three brake lights out and now fuse blows only when I push brake pedal. Then i thought maybe was socket. Replace two of six, still blowing fuses. Now about to recheck each socket one at a time and the third light wires. If that does not work then I am in bad way.
Please, any ideas?

The hot wire that goes to the brakes is shorted to ground. that is the only way for it to blow the fuse.

I think I finally got it right. I realized that I somehow put back two sockets that were bad and kept out the good sockets (I was very tired and aggravated by then and had several interruptions) careless oversight on my part.
All good sockets are in now and so far the fuse is also still good.
Still have nine of the twenty five pack of fuses I bought.

Here is a trick to put in your memory banks for the future:

A simple trick to finding a short is to replace the blown fuse with a pair of spade terminals, then use small jumper wires to connect them to a twelve volt light bulb. A brake light bulb works well. When the circuit is live and the short is present, the bulb will be full brightness and hot so be sure it is not laying on the carpet or against a plastic door panel. Now you can unplug electrical connectors and move things around to see what makes the short go away. When it does, the bulb will get dim or go out.

Right rear and cyclops light not working. Left side is fine. Checked bulb and fuses all okay.

If left side works then check wire leading to right under vehicle it may have broken otherwise it may be a can/bus problem or module problem and will need scanning for codes by a mechanic. See picture.

Tail lights are repeatedly going out. Now they will not come on at all. I have replaced the fuses but they blow every time I use the lights. It is just the rear lights. The front lights work fine. I am truly frustrated and really want this fixed as this is my only vehicle. I need help. I just spent 700 bucks to fix the rear lights and they are doing the same thing all over again. Is it a wire? And if so how do I fix it? I have changed bulbs among other things. I need help.

Did the repair that was done before correct the issue for a while? If so then I would look into that being the same issue.

JohnnyT73

Thank you for responding.

You are correct. The issue was fixed for a while. It was working great, then it just failed once again. It is truly annoying. Shelling out another 700 bucks, isn't something I want to do for temporary work. Then again, it could be this faulty vehicle. I will keep trying though.

Thanks

CJ MEDEVAC

I will try your avenues that you have presented. Once I have tried I will update on my progress. I really hope this solves the issue. I will keep you posted.

RP

I reckon i coulda suggested unplugging both assembles completely, and also doin' the "one at a time thing"

While you have it out, inspect the wires at the connection to see if they have been pinched or rubbed raw and grounding out.

This might eliminate more internal possibilities within the fixture itself, before getting more involved in the rest of the wiring

The medic

Brake lights do not work if Head Lights are on..Head Lights Off-Brake Lights work...Please HELP!~

[quote:401d24e33a="197cole"]Electrical problem
2003 Jeep Grand Cherokee V8 Four Wheel Drive Automatic 94,259 miles

Brake lights do not work if Head Lights are on..Head Lights Off-Brake Lights work...Please HELP!~[/quote:401d24e33a]

my passenger side brake lights work but not the parking lights and its the same bulb, why?

dual filament bulb, different voltage circuit. The black wire with yellow tracer should be voltage for tail lamp, the other one is for the stop lamp.

brake lights keep going out

Check the brake light switch under the dash at the top of the brake pedal. Make sure it is tight and properly adjusted. Also, make sure the wiring plug is tight.