Brake light and ABS warning

Mine did that and GM told me it was the wheel speed sensor,and I should just wait for the hub to go bad because it is built into the hub.So six months later guess what,the hub was making noise in the turns and 600 dollars later ABS light off and hub fixed.

Hope it turns out to be a simple solution. If you find you need to repair / replace the ABS unit there are some outfits you can find on the web that rebuild them.

Good luck,
Stu

drcook wrote:
Sometimes with Duramaxes (or any GM product using the same parts) you can get some corrosion under the sensor where it attaches to the hub. It will lift it up a bit. This can cause the system to trigger a warning.

Or the sensor itself went bad. We had a sensor go bad and it allowed the brakes to pulsate when coming to a stop and jump forward a couple feet after stopping. This was on our 2004.5 not too long after we bought it.

I am having an intermittent ghost like that myself. When I pull the summer tires and put the winter/storage tires and wheels back on, I am going to check the wheel sensors.

Now I realize you live in the land of no rust, but that would be the first place I would check as all it involves is some time on your part.

These trucks can also get false messages from the ground under the driver if it gets enough dirt/corrosion to interfere with the ground.

Just as an aside (and not suggesting this is the issue), how long has it been since your brakes have been bled? With the GM ABS units, if you ever work on the brakes and get air into the ABS unit, it will have to be bled out at the dealership. It takes a Tech2 unit to open and close the 6 valves in the ABS to get all the air out of it.

X2

tuna fisher wrote:
Driving home yesterday from the coast my ABS light and brake light on my dash both came on, anyone experienced this before? If so what was the problem?

Mine is a Dodge and 2001. So electronics in same time era at least in pick up. My brake controller is from our first trailer 1983? My best guess after having this problem a couple times.

Being it cooled off during the night...

If warning lights STILL on even after cooling down overnight... check for ABS wiring being disconnected somewhere. With mine a wire got disconnected just above differential cover. Disconnect caused by road debris.


If warning lights NOT on...warning light did there job to give warning about warmed up brakes. Adjust brake controller so RV does more stopping. Easy to overheat in town with RV doing very little stopping power. Or brake controller is not putting enough elec to RV.

after more research, there is a ground on the ABS unit also that gets "ungrounded" if the ABS electronics are bad, here is a write up

http://www.duramaxforum.com/forum/2001-2007-5-gmt800-non-powertrain/155892-lb7-ebcm-replacement-how.html

Does your cruise control work? If not, could be the brake light switch.

Sometimes with Duramaxes (or any GM product using the same parts) you can get some corrosion under the sensor where it attaches to the hub. It will lift it up a bit. This can cause the system to trigger a warning.

Or the sensor itself went bad. We had a sensor go bad and it allowed the brakes to pulsate when coming to a stop and jump forward a couple feet after stopping. This was on our 2004.5 not too long after we bought it.

I am having an intermittent ghost like that myself. When I pull the summer tires and put the winter/storage tires and wheels back on, I am going to check the wheel sensors.

Now I realize you live in the land of no rust, but that would be the first place I would check as all it involves is some time on your part.

These trucks can also get false messages from the ground under the driver if it gets enough dirt/corrosion to interfere with the ground.

Just as an aside (and not suggesting this is the issue), how long has it been since your brakes have been bled? With the GM ABS units, if you ever work on the brakes and get air into the ABS unit, it will have to be bled out at the dealership. It takes a Tech2 unit to open and close the 6 valves in the ABS to get all the air out of it.

Could be ABS module $$$$$$, OR if lucky like me, a bad brake light switch! $12.99 fix and 10 minutes of my time.
Just an FYI have the ABS codes read at local parts house for a good idea of the cause.
I did find this sight for module rebuilds.

http://modulemaster.com/rebuilds/

It could be the hub bearings on the front , once they get too far out of wear limits they can set off an abs light, there is a sensor in them for the abs

I stuck my toe under the brake petal and pulled up slightly and that told me it was a brake light switch needing adjustment. Give it a try.