First off i have an 86 jeep MJ, Ive been searching this site and many others to try to figure this out. My lights turn on when i turn them on, head and tails, the hazards work, the blinkers work, the switch is fine, but still no brighter lights when i apply the brake. Can anyone please steer me in the right direction before more cops around ne know me by name? Plz, and thank you.

 

Run a continuity test

 

bulbs????

 

either the switch activated by the brake pedal, or there is a fuse blown, or both of the filaments in both of the brake lights (they are dual filament, one for running lights, one for brakes) are both shot.

 

How do i go about doing a continuity test? I have the probe thing with a light, the tester, but what do i test? The wires themselves or where the bulb touches? Im not too great with electrical but i can do it if im told what to do.

 

I'd check the brake switch first.. contort yourself into the driver side footwell so you can see it. When you press the brake you'll see the plunger drop away from the pedal lever. Make sure there is a small amount of space between the lever and the plunger. If the plunger can't protrude far enough, adjust it til there's a little space, or hopefully til your lights come on. If it's good or that didn't fix it, at least you've ruled out the switch. Next, I'd check the bulbs themselves.. pull 'em out and put 12v to 'em, both filaments. If they're good, use a volt meter(not a continuity tester) and put the probe in the socket touching each of the two connections.(got your lights on?) You'll need someone to press the brake pedal for the brake side, but the running light side should show 12v. I don't know what to do next if there's no volts to the brake lights. Maybe make sure the grounds are good.

 

You should check the switch for continuity per the factory service manual. If the switch seems to be the problem you can pop the back of the case off and more than likely the first contact behind the switch isnt making contact when you push the brakes. I bent mine with a pair of pliers so that it would make contact again. Saved 25.00!

 

So... what'd you find out, anything?

 

I ran through everything, wires, switch, fuses, connection to the fuse box, the lights themselves, the sockets and etc.. I finally came to the conclusion that i hate wires. Also i found that the mount that the switch is on was loose. Thank you all for your help.

 

So, did that fix your issue?

 

Yes it did, after I positioned it at a few different angles. I found the one angle that worked, tightened it up, then drove through a bumpy field to road test it, and it still works.

 

Well, congrats. Glad to hear it.