Brake Light Issues

[305ian]

Hi all-
New to the forum and I apologize if this has already been discussed, but I couldn't find threads like my issue and was hoping to be pointed in the right direction...
My 2000 Sahara's main brake lights (third light works fine) don't work unless the the running light /headlight switch is turned on. Hazards work, no obvious fuses blown and all other lights, turn signals etc. function as they should.
Any suggestions on where to start?
Thanks!

 

[P man]

Hi all-
New to the forum and I apologize if this has already been discussed, but I couldn't find threads like my issue and was hoping to be pointed in the right direction...
My 2000 Sahara's main brake lights (third light works fine) don't work unless the the running light /headlight switch is turned on. Hazards work, no obvious fuses blown and all other lights, turn signals etc. function as they should.
Any suggestions on where to start?
Thanks!

Welcome to the forum.

May I assume both bulbs are good?

 

[TJ4Jim]

Hi all-
New to the forum and I apologize if this has already been discussed, but I couldn't find threads like my issue and was hoping to be pointed in the right direction...
My 2000 Sahara's main brake lights (third light works fine) don't work unless the the running light /headlight switch is turned on. Hazards work, no obvious fuses blown and all other lights, turn signals etc. function as they should.
Any suggestions on where to start?
Thanks!

One of the more common with the rear lights is a bad ground so remove the housing from the tub and clean any corrosion on the tub, mounting bolts and inside the fixture where the bolts are seated.

 

[305ian]

Welcome to the forum.

May I assume both bulbs are good?

Yes.

 

[305ian]

One of the more common with the rear lights is a bad ground so remove the housing from the tub and clean any corrosion on the tub, mounting bolts and inside the fixture where the bolts are seated.

Wouldn't a bad ground affect the brake lights in any position?

 

[B1Toad]

At the brake pedal switch there is a white/tan wire that leaves with the brake light signal. It passes thru connector C108 then to C322 where it then splits and one side goes to the turn signal switch and the other goes to splice 315 which is up under the fender lining by the right brake light. Since your high mount brake light works we know the signal makes it that far so I suggest you check splice 315 near the right brake light. If there is no signal there go back to connector C322 which is the black one in the stack of colored connectors up in your left kick panel and check to see that both white/tan wires have a signal when the pedal is depressed. It is also possible there is a problem in the turn signal switch which normally cancels the brake light on the side you are signaling on. As far as grounds, each tail/brake light assembly is individually grounded.

 

[SomeMidwesternGuy]

I had a similar issue, albeit my right turn signal was a bit wonky, and it ended up being the turn signal switch. I also replaced the brake light switch behind the pedal just for peace of mind. Both parts are incredibly easy to replace.

 

[B1Toad]

Here's a diagram showing how the brake light signal passes thru the turn signal switch, I am thinking there is a good chance your problem is in the switch.

 

[B1Toad]

SomeMidwesternGuy beat me to it!

 

[SomeMidwesternGuy]

SomeMidwesternGuy beat me to it!

Haha only because I fixed that headache about a week ago!

 

[TJ4Jim]

Wouldn't a bad ground affect the brake lights in any position?

When troubleshooting anything its best to start with the simple things and cleaning grounds is easy and then you'll know for sure they are good.