no brake lights

[FranceJohnson]

Did you every find the solution to this puzzle? I have the same issue going on now, also a '92.

Tail lights work
1157 NEW Bulbs
New 10A Fuse
Tested/Confirmed 12V at BRAKE fuse
No power at rear plug
Does have trailer converter box piggy backed but turn signals marker lights work (on car and trailer plug). Good continuity from splices to the pin inside the light ballast.

So, I dont have power somewhere between the fuse and harness in the back.

 

[MTrun]

Trying to resolve this one myself now. Tail lights work, no brake lights however. Bulb replacement check. Fuse verified check. +12V at STOP fuse, but drops to +0V when I press the brake pedal. I think I checked the ID2 pin 2, and has 0V there. Tried disconnected every connector I could find in the quarter panel and still had the fuse drop to 0v when I pressed the brake pedal.

UPDATE - pulled the stop switch verified functionality & replaced...no issue there.

 

[jonheld]

Trying to resolve this one myself now. Tail lights work, no brake lights however. Bulb replacement check. Fuse verified check. +12V at STOP fuse, but drops to +0V when I press the brake pedal. I think I checked the ID2 pin 2, and has 0V there. Tried disconnected every connector I could find in the quarter panel and still had the fuse drop to 0v when I pressed the brake pedal.

UPDATE - pulled the stop switch verified functionality & replaced...no issue there.

Have you downloaded the EWD for your vehicle?
Otherwise you're walking around in the dark without a flashlight. The stop light circuit is pretty simple.

 

[MTrun]

Have you downloaded the EWD for your vehicle?
Otherwise you're walking around in the dark without a flashlight. The stop light circuit is pretty simple.

Thanks Jonheld, fair point, will start there. I have it and was hoping I would stumble on something easy but to be honest was pretty much doing exactly what you warned -- walking around in the dark last night for way too long...

There are a few abandoned wires as well that don't give me confidence (i.e. old subwoofer wires, old car phone wires and a security bypass switch a PO put in).

Will start with the EWD and post what I find out...

 

[MTrun]

Thanks Jonheld, fair point, will start there. I have it and was hoping I would stumble on something easy but to be honest was pretty much doing exactly what you warned -- walking around in the dark last night for way too long...

There are a few abandoned wires as well that don't give me confidence (i.e. old subwoofer wires, old car phone wires and a security bypass switch a PO put in).

Will start with the EWD and post what I find out...

FOUND IT!!! After 3-4 hours of troubleshooting it was the fuse! Head against brick wall emoji here. Fuse was still good (had checked it 2-3 times already), but seems it had a bad connection in its slot on drivers left knee fusebox. Cleaned it up with emery paper, wiggled it and problem solved. The only indication was a small black spot on one leg where it was shorting, and with some wiggling found the brake lights came on briefly. May be time to replace all the fuses, or even the box? Working now though.