GRR! brake lights not working!

[e_racer1999]

well.... i don't know what happened, but all of a sudden my brake lights quit working. it's not the bulbs and there aren't any obvious problems. coincidentally (or not) when i turn on my lights the left connector of the "tail" fuse gets hot and has since melted the plastic (GRRRR).... HELP! this is my daily driver and only car, and before anyone tells me to search i already have to no avail.... anyway, thanks

[Inf]

If the fuse is getting hot without breaking the connection, I would guess that the problem(or at least part of it) is with the fuse block itself. Often the connections get corroded and as a result create resistance which makes the pieces act like heating elements. There are some threads about taking care of a corroded fuse block. I remember reading someone suggesting soaking the entire unit in vinegar for a number of hours as the acetic acid reacts with the oxidation.

[e_racer1999]

cool thanks! ya, i read a bunch of different threads and pages about the problem, just not how to fix it! anyway, would that help my problem w/ my brake lights? b/c as of now i have no car....

[Inf]

It might, sometimes when the fuse block melts it can cause the connectors to have intermittent connections. I had this problem with my parking lights/taillight fuse. It melted the black lower part out around the connection so that when the car vibrated (i.e. engine running, moving, etc) it will break the connection every so often. It is only held together by a rivet, which sometimes isnt tight at all after all these years.

I failed my first inspection because of this. Luckily a club member managed to help me out with a good fuse block back then.

Another thing to check would be the brake light switch which is mounted under the dash on a bracket that sits in front of the brake pedal arm. It should be easy to locate once you get down there. A wiring diagram would be helpful. I haven't looked but i'm guessing the switch operates in series with the whole circuit, so you would want to check if it goes to ~0 resistance when the brake pedal is pressed.

[Ed]

The brake light switch is located on the brake pedal under the steering column. I'm no electrician but that's where I would start. Use a voltmeter or tester and follow the wires until you find a drop in voltage. And like Inf mentioned check and clean your connections. Also check your wires to make sure there isn't a short somewhere. You can purchase this stuff called "dielectric grease (sp?)". It's used for ignition wires to prevent corrosion and to aid in conducting electricity. Try putting some of that on the connectors after you clean them.

[e_racer1999]

thanks guys... i looked at the switch earlier and it APPEARED fine, but appearances are sometimes misleading. the only thing that kinda tossed me was that the brake lights stopped working and the fuse box got hot at the same time. this is what is leading me to believe that there's a stupid short in some hard to get to area at a common junction. anyway, i'll get out my multimeter when i get home from work and check la resistance...

[Alfadog]

Don't want to appear a simpleton, but if your fuse is melting the fusebox you might also want to check it's the right kind of fuse once you fix the problem. I'd guess your problem is what Inf said -"sometimes when the fuse block melts it can cause the connectors to have intermittent connections."

[e_racer1999]

okay cleaned and fixed my fuse block. check. now for the toughie.. the brake lights. they STILL don't work. tested the brake switch: operating perfectly. it appears that somehow the green/yellow wire that runs from the fuse block (+) turns into a negative (-) wire at the combination switch and brake switch. does anyone know if this is how it's supposed to be? i used a test light between the fuse block and the green/yellow combo wire and it lit up. if this is how it's supposed to be PLEASE let me know so i know where to look for the short. also, does the hazard switch do that or could it be burned out? the hazards still work which is throwing me off... anyway, thanks!

[Inf]

I would check to make sure the circuit is grounding properly as it is drawn in the wiring diagram. I think a lot of electrical problems eventually get traced to a bad ground. (or a ground in the wrong place, i.e. a short)

I can't seem to find the file section, so I guess i'll upload the wiring diagram that used to be there here in case you don't already have one.

A good place to check would be the turn signal switch and the hazard switch. From glancing at the wiring diagram, the circuit runs through both of those parts. I would make sure continuity is right for the different switch positions like is shown in the diagram. Sometimes the internals of the switch will totally flake out on you and cause trouble. I ended up having problems with my dash/parking lights because of a burned out rubber part inside the combination switch : the lights would flicker and sometimes just turn off when going over bumps! scary! I did a temporary fix with some epoxy, but i'm still not too confident about it. I am thinking about just biting the bullet and buying a new combo switch (if I can find one that is).

You could try jiggling the switch when you are testing it, sometimes continuity is intermittent only when some loose piece is in a certain position. This was the case with my combo switch. I haven't ever gone over the turn signal switch, but I am guessing it is suscepitible to the same kind of failure.

[e_racer1999]

thanks for the file, but i've already been perplexed my FSM AND my chiltons.... this is getting so annoying! it sucks having to work all the time and not fixing my car... anyway, thanks for all of the help!

[gundee]

The brake light circuit and the hazard circuit use the same fuse. If the hazards work then that fuse is good.

You did not say how you tested the brake switch. You used an ohm meter I assume?

The other way to test it is to pull both wires off brake switch and take a short piece of wire and jumper those two wires together. If the brake lights go on then you have a bad brake sw.

[e_racer1999]

yes, i used an ohm meter.... AND i tried jumper....ing.... the wires but to no avail. tomorrow i get half a day off so i'm going to continue troubleshooting this... the time and experience is worth saving the hundreds of dollars....