I recently bought a '96 Eddie Bauer Bronco that seems to have been pretty well taken care of. Everything works great except for the brake lights. Sometimes they work, sometimes they don't.
The center brake light above the rear window works fine every time, but the main brake lights quit. Turnsignals work fine, 4 way flashers and tail lights work fine

Today I was checking all the wires under the rear of the Bronco and all is fine as far as I can tell, including the trailer plug. The tail light bulbs are new. I removed the left tail light assembly, pulled it away from the body, and low and behold, the brake lights started working. I replaced the assembly and the brake lights are working fine now, but they will quit again at any time.

Any guesses or Ideas as to what the problem might be? I can see no bare wires behind the tail light and the light socket looks good as far as I can tell.

One more note, it's both main brake lights that quit and started working again. I only removed the one assembly.

TIA
Jim
'96 Bronco Eddie Bauer 5.8 AT
'03 Ranger XLT 4.0 AT 2x4
'02 Merc Grand Marquis
'01 GL1800 Goldwing

 

I believe it may be your turnsignal switch. Ford calls it a "multi-function switch". Click on the link below and look at the diagram. On the top left you will see the brake switch. Power flows down through the brake switch to the light green wire. You will notice it splits direction, with the center high mount brake lamp being fed directly by the brake switch. The other direction goes into the turnsignal switch. It flows through the switch, and then to the rear brake/turn signal lamps. It has to flow through the switch because the brake function and the turn signal function actually use the same filament in the rear bulbs. Since you said the high mount bulb always works, then a good assumption is there is something wrong with the turnsignal switch.

http://www1.autozone.com/images/cds/...3d800a3a5f.gif

 

I would also check to see if you have a short in the brown wire coming off the "main light switch" and the two bulbs.

 

Brown wire is for the marker/tail lamp circuit.

 

Another look at the diagram suggests another possibility. The light green wire from the brake on/off switch to the multiswitch could be shorted.

Franklin2

Yes, but it's also the only other commonality for both tail lights. The probability of that being the cause is low however...as it would have to be shorted in two different places. I should've looked a little more at the diag, but hey it was a long day

 

Thanks guys. Right now they're working again and all I did was unbolt and pull the left tail light houseing away from the body. They started working. I replaced the tail light and all is alright for now.

I appreciate the suggestions. If I don't get this thing figured out soon, I'll just take it to the dealer and let them figure it out.

Thanks again
Jim

 

where is the turn signal switch "multi function switch" you refered to located. every light but main rear brake light works

 

All Brakes lights are on the REAR.


The Multi-function switch is that lever switch on the left side of the steering column.

 

bigblue85
If your truck is an '85, you don't have a MFS - just a turn signal & hazard switch inside the column.

 

Well everyone. I posted on June 1 that the brake lights were working and all I did was pull the left tail light assembly away from the body. Well, here it is a month and a half later and they are still working. I guess I won't worrie about it till they quit again. So far, so good.

Thanks again everyone.

Jim