The brake warning light comes on intermittently on my '96 Ram 2500 4x4 truck. Anyone know what typically causes this light to come on and what I might do to troubleshoot this issue? The brakes on the truck are working fine and there is no loss of fluid at the master cylinder. I replaced all of the metal brake lines in the truck with stainless steel lines a while ago, in addition to installing a late model (2000 or 2001) Dana 60 with rear disc brakes in lieu of the original drum brake Dana 60 rear. Thoughts?

 

Is it just the brake light? Or does the ABS lite come on too? Generally, that's a sign of a leak in the system somewhere, or the e-brake pedal is slightly depressed. If the lite only comes on when you actually step on the pedal, check all the joints for signs of leakage, and pull the drums to have a look at the wheel cylinders.

 

So far, no ABS light is on. The ABS light only comes on before I start the truck, then goes off. Only the light that says 'BRAKE' comes on intermittently. The light comes on if the brake pedal is depressed or not. When the light comes back on again, I'll try pressing and releasing the parking brake pedal to see if it has any effect. I hardly ever use the parking brake pedal to set the parking brake, so I thought it wasn't the parking brake, but who knows with an old truck over 25+ years old..

 

I work on three '98s, a '99 and an '02 all with a constant brake light. I think it's the ABS module because everything else checks out.

 

That wouldn't surprise me. The ABS module for my truck is just for the rear wheels and is a block located near my master cylinder with an electrical wiring harness that plugs into the bottom of it. I picked up a couple of those ABS blocks from a pick and pay salvage yard a while ago. I plan to swap one of them onto my truck in the not-too-distant future, as the one on my truck looks like worn from the truck's snow plow years. Seems as though Dodge used the same ABS block module on several different vehicles (Dakota, Durango, RAM, etc.).

 

you can try unplugging the wire to the proportioning valve to see if it is an electrical issue of hydraulic issue. have you also checked your rims to see if there is any obvious leaks at a wheel cylinder or caliper?

 

I will try unplugging the proportioning valve wire to see if that has any effect. There are no leaks at the calipers and all of the flexible brake lines are relatively new and braided.

 

It's an easy test to see if that switch is sticking. It would be my first test.