T-Rex of America

Gary · Posted: Sat Mar 17, 2012 5:10 pm Post subject: Brake failure light always on

Has anyone had an issue with the brake failure light? Mine is on constantly, but the fluid level switches and the brake pressure switch do not seem to be the reason and the brakes are working correctly.

Does anyone have a wiring diagram of this circuit?

mellowcmb · Posted: Sat Mar 17, 2012 9:22 pm Post subject:

I'm curious to know the answer as well. I'm having the same issue

twn454 · Posted: Sun Mar 18, 2012 12:27 am Post subject:

While parked, pump the brake pedal as HARD as you can a couple times! that should fix it

Gary · Posted: Sun Mar 18, 2012 9:10 pm Post subject:

Problem is solved.

Undid wiring harness and found the circuit also splits off and goes to one of the headlight relays. (Still not sure why)

Turns out, this is where the ground fault was. Apparently water had gotten into the relay on the left side (looking from the front with the nose removed) When I removed that relay the light went out. If you look at the pinout of each relay, they are wired differently. The problem pin is not used on the other relay, so I swapped the relays over and solved the problem.

mellowcmb. I would start by removing the relays. If that turns the light off, try swapping the relays. You should be able to try that without removing the nose. I hope this saves you undoing the wiring harness like I had to. That is a bear!

Gary