Kid1823

I have a 1991 jeep cherokee automatic 4.0L; as the title states my brake lights and reverse lights are not working. But all other lights work (turn, headlights, tail lights, interior lights, dash, console).

Have checked and replaced all fuses

Replaced the bulbs

Replaced the brake switch

After all this the brake lights and reverse lights are still not working. Any ideas would be appreciated

jeepsurfer1

100% the nss, let me find the link...

jeepsurfer1

http://go.jeep-xj.info/HowtoNSSrebuild.htm
hear you go, take your time and read it twice. best of luck!

Kid1823

Thank you for the information; Is that a fix for just the reverse lights or does it fix the brake lights issue too?

jeepsurfer1

o wow i should have read the whole thing i would see if they have come un plugged,

these are the wires you will find behind the panel in the rear area, if they are all plugged in and secure then i would say you have some wiring gremlins to work out, keep me posted and i'll help in any way i can

jeepsurfer1

but the nss is known to kill the reverse lights, but also when you push your foot down on the brake you push a switch so my point is maybe you have TWO problems nss and brake lights due to a bad switch, im really hopeing its nothing to big like one of the wires coming unpluged but sadly i don't think thats it...

but like i said keep me in the loop

Kid1823

I replaced the brake switch and checked the connections and everything appears to be plugged in

CPLSeraphim

Maybe check your grounds. I just replsced my NSS so i had reverse lights. Take a voltometer to the light sockets and see if there is any power. Could just be the wrong bulb. I bought turn signal bulbs that were the right number, but they didn't work til I bought the orange ones. If you got power, check to see that it is not mis-shapen somehow. If there is no power... kill the gremlins, that check where the plug ins are at, then follow.

Kid1823

And now have found that my 7.5 fuse is burning out instantly after replacement not sure completely what it is for at the moment

Kid1823

Now found a wire label left turn/stop going across the rear of the jeep but not connected to anything and cannot tell where it was originally

Caish

For testing, use a wire plugged into the fuse block in the ACC hole that is empty.
Use the other end with key on, to touch a wire on the brake light switch plug.
Do they come on?
If so find that wire and where its broke, or do like I did and just run a new wire to the brake light switch.
Someone butchered the wiring in mine at some time in the past. AMC was never known for great wiring in the first place.

Kid1823

at this point I would just like to rewire it to get post this headache but not sure how to go about it

Caish

Borrowed this from elsewhere in this forum.

See the slot at the upper left corner with the ACC beside it.
USe a spade connector and plug it in there.
Assuming your not getting power to the switch.
Put a female on the other end of the wire and plug it on to the brake light switch.
On mine it was the top connector, I never did see where the OEM wire disappeared to though.
Plus I hate working under the dash so I just wanted it done asap.
Not the correct fix, but they work now.

Kid1823

So bring power from the acc access to the top connection above the brake switch connector? Have any photos by chance for reference?

Kid1823

my loss of brake lights and reverse lights ended up being a loss of power (wire had been poorly connected together by previous owner) before the relay (that controls the rear lights) in the fuse box, that is under the hood. fixed my brake and reverse lights. But ended up not touching the NSS.