Won't start with foot on brake when it's wet

[ejholmgren]

An odd thing happened the other day. Came out from REI in a downpour and the truck would not start (a few weak clicks, but no cranking). I cursed profusely for a few minutes and finally it came to life. Yesterday, it happened a second time in the driveway where I had the piece of mind to do a little more analysis. My driveway is rather steep, so I always push the clutch in, then the brake, and then pop the e-brake. I noticed that every time I pushed the brake in, the CD player would reset and display the welcome message again. Decided that was odd, so I left the e-brake on and it started fine with just the clutch depressed. It would not start with the foot brake depressed.

Can anyone surmise what's going on here? Obviously it has something to do with the lights for the braking system.

 

[RobbieD]

Wow; this one sounds like it might be a pain. The first thing I'd start looking for is weak, and corroded or discolored, wiring connections. Both on the positive side and the ground side of the wiring; especially the grounds, and be sure to check the battery connections too. A good wiring diagram of the truck is going to be your best friend, if you don't hit on an obvious problem early in the troubleshooting. Good luck!

 

[Earl43P]

Easy place to rule out the tail lights, right in the center, under the tailgate. That plug will rule out a tail light problem. Disconnect it. If problem remains, look at the Brake pedal switch wiring for something rubbing or shorting.

 

[ejholmgren]

Wow; this one sounds like it might be a pain.

That's what I was thinking.