Grand Cherokee 2000 (tail and brake lights)

Neither the brake nor the tail lights are working on my grand cherokee. It start by not working when it is cold, but when the temperature warms up, everything start working. Now, cold or worm, nothing works. Please help. What do you thing the problem (s) is (or are)?

I am sorry , I wanted to say turning lights(signals), not tail lights. It is my brake lights and my turning signals that are not working.

Start with the fuse and the bulbs (both sides could be out). When changing the bulbs, check the sockets for corrosion. If there is any, clean it ouot as best you can. I’ve used a pencil eraser successfully.

Thes are super cheap and easy things to change. Post back with the results.

it was the fuse for the brake lights. Turning light signals still not working. I put new bulbs(clean everything) and a new fuse, but nothing seems to work.

The brake lights and turning signals share the same filament. One possibilty since the brake lights work is that the flasher unit for the turning signals is defective. Do your emeegency blinkers work? I think that they share the same flasher unit. The flasher is probably a plug in unit on the fuse panel.

Like Triedaq was talking about, those lights may run through the emergency flasher switch. Try cycling the switch and see if that makes a difference. You may have to replace the switch if that doesn’t help. You should first verify that it is the switch causing the trouble before you replace it.

Neither the emergency nor the turning signal lights work. Nothing (green indicators) is show on the panel.

The problem might be with the combination flasher unit. This is located in the juction box, under the dash to the left. The combo flasher is located at the top of the junction box, third component to the right.


Does your Jeep have a trailor connector in the back? Trailor connectors fill with debris or the wiring where they are spliced into the harness corrode. Causing a short, blowing fuses, and some crazy lighting issues.

No, I have no trailor connection. I will try to replace the combination flasher this coming Monday.

Thank you everyboby. It was the combination flasher. I bought a new one this morning and it is working fine.
Thank you again.