Brake Light Switch

[WahooSteeler]

Took truck in for inspection a couple weeks ago, shop called and said brake lights not working. When I picked it up, the owner, who usually is the one that works on my truck, said he was tied up doing other work so he had another guy do it. Only thing it needed was a new brake light switch. A few days later I was behind my son while he was driving it and the brake lights were not working. Stopped in the shop at the end of the day and the guy who worked on got under the dash and said a wire was loose, sure enough they worked. A couple days later I was driving it at night and noticed in my side view mirror they were not working again. 

 

As I looked up under there tonight, I find 2 new wires hanging I don't recall disconnected before. The brake switch only has 1 red wire connected to it. There are 4 prongs, 2 pointing towards the driver and 2 pointing to the passenger side. The red wire is on the top prong of the pair facing the passenger side. I know in this picture the brown connector is supposed to go to the brake switch, but as you can see it only has 1 red wire. What wires go to the 4 prongs? I have cruise but it does not work fyi. I plan to take it back to the shop tomorrow but if this is a 2 minute fix I will do it myself. I stopped in Friday and the owner said bring it this week and he would spend some time with it to see what the other guy did. 

The wire on the left is actually a short piece of black wire spliced in to blue wire, but they is very likely from the PO who was the king of splice and tap all over the truck. 

 

*Also.......all other lights work, turn, running lights, hazards, fuse is good. Edit original post that single red wire is attached to BOTTOM prong facing passenger side. And while I'm at it, where is the ground for the tail light harness supposed to be? Manuals seem to indicate it being somewhere on the driver's side frame but I have never been able to locate it. 

 

[Ωhm]

1 hour ago, WahooSteeler said:

And while I'm at it, where is the ground for the tail light harness supposed to be? Manuals seem to indicate it being somewhere on the driver's side frame but I have never been able to locate it.

Remove LH taillamp assembly.

 

[WahooSteeler]

6 minutes ago, Ωhm said:

Remove LH taillamp assembly.

 

 

And this is separate from the fuel pump ground, correct?

[Ωhm]

1 minute ago, WahooSteeler said:

 

And this is separate from the fuel pump ground, correct?

No. G107 same ground point.

[WahooSteeler]

9 minutes ago, Ωhm said:

No. G107 same ground point.

 

Ok, thanks. I'll check it, but I'm confident it is good as I refreshed it when I put in a rebuilt fuel pump last fall.

[Ωhm]

I'll take a stab at this. Connect brown connector to one of the two switch. Using the connector with the elbow, connect that to the other switch. One pin should work with brake switch, while the other pin will leave brake lights on all the time.

[WahooSteeler]

2 hours ago, Ωhm said:

I'll take a stab at this. Connect brown connector to one of the two switch. Using the connector with the elbow, connect that to the other switch. One pin should work with brake switch, while the other pin will leave brake lights on all the time.

 

Thanks Ohm. I just came in from messing around with it. Of the 3 wires shown, which excludes the pink wire that was connected to the bottom prong, I did not try to use the brown connector yet, the one on the left with the black wire that was spliced to a blue wire with black stripe does not fit any of the prongs, the spade on it is too narrow. The blue wire with white stripe and elbow connector I tried in all 4 positions while doing the same with the existing connected red wire but no joy. I HAVE determined that it was installed upside down, which may affect the angle and/or contact points of the switch completing the circuit. Since one pair of prongs is to activate the brake lights and the other pair is to deactivate cruise, I am assuming it does not matter which prongs you use for each function. FWIW, the side with the "half circle" should be closest to the brake pedal with the open part facing down, and it is also slightly longer than the side with the hole. While researching I came across a thread on Cherokee forum indicating trouble with getting the switch in the right position. I'm gonna let the shop twist themselves up under the dash instead of me since I've already paid for the repair, fortunately the owner is really good about standing behind their work and will get it right.  

 

Picture of 4 prong (switch for MJ/XJ with CC).....

[WahooSteeler]

Switch was indeed installed incorrectly with longer "half moon" or open side facing outward instead of up against the brake pedal arm. Another wire had slipped off but the incorrect mounting was affecting the angle of the switch with the pedal stroke. Glad it was fairly simple. 

[cruiser54]

[WahooSteeler]

Cruiser, I found that photo from another thread you posted it on and took it to the shop owner when I dropped it off, plus some pictures of actual switches mounted that I found on cherokeeforum. Thanks!