Brake light on a '90?

Hi,
On my 1990 XJ, the brake light does not seem too sensitive. When I was hooking up my trailer, I was testing the lights, and the brakes light didn't seem to work. So, I unhooked the trailer, and pushed on the pedal with the key on, and nothing. When I pushed really hard, the lights on the back of the Jeep came on, but if I just put my foot on the pedal with a bit of pressure, nothing!!
It got dark, so I didn't go into it.

So, does this sound like a bad ground or a bad switch? How much pressure should be needed to apply for the light to come on?

Thanks in advance for our thoughts!
Bob:wave1:

the pedal on a cherokee travel about half pedal before the brake will actually start to grab. without the engine running you didnt have the boost from the engine vacuum making the pedal easier to press so more then likely you just werent getting enough pedal travel to actually activate the brake light switch. the easiest way to check this would be to stick your head under the dash and press the pedal down and see how far it actually travels before the switch will activate.

Ive got this same problem with my 90... The brake lights only come on when pressing on the brakes hard. With properly adjusted brake shoes, and good pads / rotors, the amount of pedal travel needed to brake is minimal... How can this be fixed?

The brake light works off of a switch contacting the pedal, not on pressure. Check the switch bracket and adjustment.

Muad'Dib said:

Ive got this same problem with my 90... The brake lights only come on when pressing on the brakes hard. With properly adjusted brake shoes, and good pads / rotors, the amount of pedal travel needed to brake is minimal... How can this be fixed?

Click to expand...

Hallo, The pressure on the brakepedal has nothing to do with the brakelights
It is just an adjustment of the brakelightswitch.
The pedal have to move forward to release the pin in the switch.
I produced myself a metal strip with adjustments bolts to make the right distance. Look under the dash and you wil see the idiot construction with the clip and the plastic screw. good luck:wave1:

I think you guys are confusing my 90 RENIX with a 91+ HO.

The Renix has a switch that is bolted through the pedal and the booster cable.

The HO's have a stationary switch that is "pressed" when the brakes are not being used. Once the brakes are pressed, the pedal's shaft moves away from this switch activating the brake lights.

Muad'Dib said:

I think you guys are confusing my 90 RENIX with a 91+ HO.

The Renix has a switch that is bolted through the pedal and the booster cable.

The HO's have a stationary switch that is "pressed" when the brakes are not being used. Once the brakes are pressed, the pedal's shaft moves away from this switch activating the brake lights.

Click to expand...

:doh:

From the FSM
Installation:
1) Install brake switch in retainer. Reconnect brake switch electrical connector.

2) To check brake switch adjustment, slightly depress brakepedal and note operation of brake switch plunger. Brake switch plunger should fully extend when brake pedal free play is taken up and brake application begins.

3) Clearance between brake switch plunger and brake pedal should be approximately 1/8". If clearance is not within specification, pull brake pedal rearward as far as possible.

4) Brake pedal should contact brake switch plunger, pushing brake switch backward in retainer to provide proper adjustment. Ensure brake lights operate.

5) Recheck clearance between brake switch plunger and brake pedal with brake pedal depressed and free play taken up. Reinstall lower steering column cover or trim panels.

The diagram and procedure above is from a 91+ not a 87-90 RENIX...:doh: :gee:


Anyway, my problem is solved. As i said in my first post in this thread, i had the same problem as the original poster. The brake lights would only come on if the brakes were pressed all the way down. I just replaced the switch with a new one, and i knew right away it would fix my problem. As soon as i pressed the brakes even 1/8th of an inch down, i could hear the switch "click" just as it should activating the brake lights.
Replacing switch = fixed problem.

BTW here is a pic of the stop light switch (aka brake light switch) for the 87-90 RENIX:

Glad you got it fixed. Where did you get the pic?

However, the text and figure above was from the 88 FSM. I have an 88 myself. I'd take a picture but it's pretty buried behind a few harnesses and other cables.

Hmm .. makes me wonder if it was different for an 88 compared to 90?? Or different for a manual? Ill scan my FSM (when i get home) and post a pic here just to add to the content.
I know its a slightly different switch for my Automatic if i had cruise control.. but i dont. I believe they look the same, just have two additional leads for the cruise circuit...
I got the pic off of partsamerica.com ... CSK (checker schucks kragen murray etc..)

I do know that the 91 plus have like a push button switch that has its own seperate bracket kind of similar to your pic that you posted.

There are certainly different part numbers for cruise vs no cruise. I have cruise with the AW4. Got no clue why the FSM says one thing and you CLEARLY have something different. The FSM didn't really state any difference I could see. Maybe I just clipped the wrong section.

But you are right, you should hear the click as soon as you push the pedal and the w/cruise has 2 extra connectors.