TNutcher

I know this topic has been beat to hell but i can't find what I'm looking for. My lights have been on for a few hundred miles and I replaced the rear speed sensor a week after the lights came on. Well the lights are still on and its been about two and a half weeks since i changed the sensor. It isn't a 4wheel ABS truck as far as i can tell (no wires to the front wheels) and from what I've read that kind of leaves me with two other options. Transmission speed sensor and ABS control unit or something that supposedly costs 500-700 bucks. Has anyone had problems like this where it wasn't the rear speed sensor? Everything on the truck works fine save the two idiot lights are on; speedo, tach, all other gauges, 4x4, parking brake - everything. I've been debating selling it and need to get this fixed properly to get a decent price. I appreciate any advise or hints. Thank you
TNutcher

fschiola

Replace the stoplight switch. It runs about $13.00 at Auto Zone.

TNutcher

where's the stop light switch and what does it do? I'd be happy if it was only that cheap part!! Thanks
TNutcher

fschiola

Follow the brake pedal up toward the pivot point, you'll see a switch facing the firewall with a plug with 6 wires coming from it. It controls the ABS, Cruise control cut out and of course the brake lights. The new switch will have instructions on how to replace it as well as how to adjust it.

Busboy

Yeh try the brake lite sw but first make sure that you have NO pedal droop on the brake and park brake.

winkle

CHECK THE FUSE FOR THE BRAKE LIGHT!

I won't tell you how I found that one out, its to embarrassing.

TNutcher

How do you get rid of pedal droop? I put in a new stoplight switch and it did nothing. My brake pedal can be pulled back about 1/8th of an inch from its resting position. Thanks
TNutcher

winkle

Tnutcher:

Do your brake lights come on when you press down the brake pedal.

bandit408

Check the fuse for your trailer lights and abs. Seen many at the dealer that when you drag the trailer pigtail on the ground it will pop the fuse and turn on the abs and brake light on the dash.

TNutcher

winkle - yes the do at the correct interval. I ruined one stoplight switch and had to replace it. When I installed the first one, I did it wrong and the lights/cruise wouldn't come on/ disengage till halfway down the stroke, now it works like it should - cruise comes off with just a faint tap.

I'll check all my fuses but I'm pretty sure I looked over all having to do with brakes/abs but i'll check trailer and the others again. . . grr this is annoying!

I checked my truck with my friends smarty and it had one dtc 1693 and said companion for JTEC or something. I know this code appears often for others as a companion code but never heard about the JTEC. Does that have anything to do with the abs, speed sensing or brake system?? or just left over from an old code like my past 0216 or something??

Thanks
TNutcher

Busboy

1/8 inch droop is ok I've seen some that make contact with the sw. JTEC I think refers to the PCM (made by JTEC). So you have a code stored in the PCM (power train control module) and you need to read it.

TNutcher

Well checked all the fuses and still nothing. wiggled the plug wires on the differential and took them out and cleaned the plug. I already changed the sensor there. Isn't the PCM read through the obd2 port which the smarty would have shown?? I'm at a loss. . .

Also sometimes both the abs and brake lights go out as they should at startup and come on maybe 2 or 3 seconds after they go off. . . Is this any indication as to what part of the system its in? or something?! haha maybe i'm just wishful thinking. . . well anyway. . . any thoughts on the abs control module up by the fuse box?? I've read that sometimes it is this that is the problem though i've also read that it runs 5-700 dollars. Any thoughts?? Thanks and appreciate the responses keep helping me out please!!!
TNutcher

Hercules

This happened to our Olds Bravada several times. Granted, different truck, and it's 4 wheel ABS, but, the theory still applies. Trace, or check for continuity, all the wires that are involved with the ABS. Your looking to rule out a break in one of the wires. Yes, I did say a break. In our case, it was the pigtail lead to the left front wheel. The only thing I was able to determine as the cause of the breaking was one fo the wires must have been pulled tighter than the other when the casing/insulation was applied around them. In each case, the same wire would break...until I repaired it enough times I effectively lengthened the wire. Anyways, when one of the wires breaks, it doesn't short out, blow a fuse, or anything else. It simply throws the ABS idiot light on, causes the ABS to not function, and saves a code in the computer. I can't remember the exact wording of the code in our case, but, I remember it indicated the left front sensor. Obviously, it was usless with the exception of directing me toward the left front wheel ABS as the area of the problem. I believe it would be worth looking into the condition of the wires, since you appear to be running into dead ends.

fschiola

I think Hercules is on the right track. A while ago Shovelhead posted that he found the wire to the sensor rubbed through on a frame member. Worth a check anyway.

Busboy

The park barke sw would give you the same effect. Even if theres no pedal droop on the PARK brake, (to make the sw contact) try disconnecting the wires temporarily to see if that fixes.