Weird electrical problem

i dont know how long its been doing this but i just noticed it today. i parked by truck pulled the key out of ignition and with my foot still on the brake opened my door. i heard the buzzing indicating my lights were still on, so i went to switch them off only to find they were already off. when i lifted my foot off the brake the buzzing went away, so i pressed the brake again and the buzzing started again. late to class i thought nothing of it. when i got home it did the same but this time i noticed with the reflection of the garage door that my right corner lamp was lighting up with the brake. is this some kind of relay malfunction? where should i begin. 1998 2.7L 4WD

 

I've got 1st gen wiring diagrams at home, can peek at them and see if we can figure it out. But it won't be until later today, gotta get kid off to school then have an interview.

 

my question did you splice in trailer wires??
if so thats ur proulblem you wired the brake lights with the lights that come on with the head lights (i dont rember the name of them but they are the th lights that come on when you turn the head light on)

 

wow i forgot all about this. i did look at the wiring diagrams for the 1st gens. The tails and brake light circuits don't even share the same fuse, so this makes no sense.

higherlux has a good suggestion, did you do any wiring somewhere?

(btw welcome higherlux good start)

 

thanx hernameislucy
i have had the same experence with this proulblem not to long ago (when i had to redo my trailer wires for ripping a wire out of the harnnes from being pulld out) and i wired the brake light with the tail light which caused every time i hit the brakes the headlights would turn on

 

The original poster's issues are probably the result of a wiring fault in the taillight units or the lines leading to / from them.

The front corner lamps are powered off the taillight circuit in the 1998 - 2000 generation. This circuit is fed through the 10A Tail fuse. This same fuse is the power source for the light reminder features.

However, no fault in the taillight or light reminder circuit alone would explain why the behavior seems to be controlled by the brake pedal. The only place where the brake light and taillight circuits interact is at the tail lamps (and / or wiring in the rear of the truck).

The most common causes for this sort of weirdness are:

- wiring in aftermarket or transplanted tail lamp units with an incompatible grounding scheme
- foul-ups in wiring up a trailer / towing harness

A basic short in the tail lamp unit could also explain it.