Different take on the brake light / turn signal problem

1991 Cherokee Sport...

I've done some research on this and see where there is some correlation between the brake lights and turn signals not working.

However with mine - the problem is that they are all working - just at the wrong time. When I hit the brakes, my rear turn signals light up (as well). My turn signals still operate as they should, but everything on the back the Jeep lights up each time I stop.

I've checked, and it does not seem to matter if the rest of the lights are on or off - I get the same problem each way.

Any thoughts?

Trailer tow wiring problem? Check to see if there is something wrong with the tail lamp converter, maybe even corrosion in the trailer plug causing a problem.

I'll take a look at that tonight. I've had this Jeep for years, and it's had the same the towbar and wiring harness down there since I bought it.

I don't know if this would have anything to do with it, but the Jeep sat in my garage for a little over two months while I was in the process of moving from GA to OH. I followed my wife up here just a few days ago when we went home to retrieve this Jeep and everything worked fine. This seems to have just started two nights ago.

Maybe it just does not like snow...

I had a simular problem on one that I sold, but mine would turn the flashers on if you braked, then turned the right turn signal on while braking... Never could fiqure it out.

Re:brake light / turn signal problem

Hey Two Jeeps,

Did you ever figure out your problem? I have exactly the same problem; brake activates all 4 rear lamps (not reverse). Additional symptom is right turn signal (or hazards) on with brakes goes dim and stops flashing. That makes me think bad ground.

Been poring over wiring diagram from Haynes book, but no good ideas. Trailer wiring relay (Curt) goes from 5 wire to 4 wire. Voltmeter on the trailer connectors shows 0.4 V across left turn to ground, with all lights off. My connectors are pretty corroded, all bulbs are good. Fuse has to be OK, or no lights at all.

Any electrical wizards out there got any ideas?

ScottB KY

Re: brake light / turn signal problem

scottbky said:

Hey Two Jeeps,

Did you ever figure out your problem? I have exactly the same problem; brake activates all 4 rear lamps (not reverse). Additional symptom is right turn signal (or hazards) on with brakes goes dim and stops flashing. That makes me think bad ground.

Any electrical wizards out there got any ideas?

Click to expand...

Thats my idea

Didn't need to. It seemed to fix itself.

A little detour if you will....as my name states, I have two Jeeps: My 91 Sport and a 97 Grand Cherokee. The GC has an interesting little problem with the dash lights - they only work below freezing! Silly as that sounds, I've put 150K miles on this thing and that's the real deal. Since I just moved from GA to OH, I was lucky enough to have functioning lights for most of the winter this year.

Not to be outdone - the Sport has decided to play along as well. This brake light problem only seems to be there when it's below freezing. As soon as it warmed up, the problem went away.

Sorry to offer a more scientific answer, but that seems to be the case. I should be able to verify it this winter.

Dang! My problem just went away, too!

I had the cold weather = no dash lights problem on an old Chevy Celebrity. The problem was corrosion on the wiring harness connector to the meter cluster. I took the meter cluster out and cleaned the contacts to fix. I guess there was enough expansion of the connector to make contact when it warmed up.

OT: I grew up just down the road in Newark, OH. Make sure to go to the July 4th street fair! It's a great small town carnival and parade. Lotta fond memories...

ScottB