HarryK

So the effort continues on fixing all the probelms on the new to me 2004 Supercab 4WD 5.4 183K.

Next on the list is the parking brake lamp which is always on. While I was still diagnosing why my driver's control won't work my passenger window, I pulled the trim panels around the parking brake to get a look at where the wires are going from the driver's door. I think it's a distraction defense mechanism because I don't want to deal with the electrical problem with the windows.

Anyway, found the plunger switch on top of the bracket which is forced in when you release the parking brake (so plunger in equals light off). figured it was bad but after pushing it up and down, it didn't seem to correlate with the light shutting off. In fact, when I removed the connector, the switch remained on so I figured it was some king of ground completion circuit if the switch was operating properly.

But, I tested the switch off the truck (I think I did it right because the contacts are so small). and I think the ohm meter results indicated the switch was working.

So then I drive to go get my first fuel since buying the truck and the light flickers on and off while I driving at different times. So now it points to the switch is good and something else is giving power to the lamp.

Can any techs tell me what else activates the lamp? I will go from there.

Thanks!

nrivera04

Low brake fluid is the easiest thing to check that would turn the light on. A loose wire in your instrument cluster is a more involved issue but common with this generation.

xMUDKINGx

I had a similar issue with my parking brake light, I literally got under the truck and gave a good swift yank on the parking brake line that goes from the cab to the rear axle and it magically turned off. Got that tip from someone else on this forum some time ago. Worth a shot and it's free

techrep

iTrader: (1)

The parking brake release levers on the rear hubs get corroded and do not release correctly.. This could be your hang up ..

tradosaurus

Bringing this thread back to life. I have the dreaded parking brake light that stays on.

I tried pulling up on the parking brake pedal while disengaging the parking brake, pulling the parking brake cable underneath the truck, replacing the brake reservoir switch. All to no avail.

My last option will be to look at the gauge cluster but I was hoping it was something easy.

Also when I unplugged the sensor under the brake reservoir the light still stayed lit.

techrep

iTrader: (1)

What did the parking brakes look like ?

tradosaurus

As I was changing the rear brake rotors and pads I noticed that the passenger side parking brakes (emergency brakes) were coated with gunk from, what I guess, is a bad axle seal on that side.

I cleaned the parking brakes and brake hardware with brake cleaner before assembling the new rotors.

techrep

iTrader: (1)

Did you exercise them to ensure they were working properly?

powerranger262

Smack the upper left side of the dash, above the cluster, light should go off. It will come back on, but you now know it's in the cluster.

Mod (Ret.)

The switch completes ground to the light, and not "power". This is done to prevent sparking when a switch such as this is operated.