ABS and Brake Light During Rain

[Cadillacmak]

In our 2001 Yukon, when it rains or we go through a puddle, the ABS and brake light come on. I crawled around under it the other day and checked wiring and connections and I dont see anything wrong. Next I will use a pressure washer attachment to roll under each area to help pin point where the problem is.

Anyone know of a common problem with these ABS systems and water?

 

[stutaeng]

I've never had that on my GMT800s, but on our Express van I once started it up and it had been raining and the stabilitrak light came on, but it went away when I put it reverse...

I'm guessing it's a wheel speed sensor issue? I believe some scanners can pull those codes? I have a Topdon bi-direction dongle and remember it shows information on wheel speed sensors. I haven't plugged in a while. I think it only had like a 1-year subscription?

 

[Cadillacmak]

I put new AC Delco hubs on it so I am really hoping its not the wheel speed sensors. The plugs all look good.

 

[ORVietVet]

I put new AC Delco hubs on it so I am really hoping its not the wheel speed sensors. The plugs all look good.

Your new hubs did not come with new sensors already? When I look up the AC Delco hubs, they have the sensors? Or are you saying you hope it is not the new hubs/sensors?

You said you crawled under and checked wiring and connections. Where? Checked related ground(s)?

 

[Cadillacmak]

The hubs came with new sensors so I checked all the connections again and at the head unit under the truck, and checked wiring for rub/cuts. I should pull and clean grounds next!

 

[ORVietVet]

Any movement on this or did a sudden snow storm come through and you are snowed in?

 

[Cadillacmak]

Any movement on this or did a sudden snow storm come through and you are snowed in?

No, I haven't got back to that one yet. Poured a concrete slab, sold my camper, fixed some stuff on the 89 I am selling, and the job. Its nonstop right now but I will work it in. Its has a squeak too, kinda sounds like an alternator, need to get at that soon.

 

[Tonimus]

If you can, use a scanner to watch the wheel speed values and drive through a puddle. That will narrow down your search I believe the ABS only uses the speedo for the rear and sensors for the front, though. Not a lot to check. Checking the wires and connectors from your front hubs would be prudent.

 

[AuroraGirl]

If you can, use a scanner to watch the wheel speed values and drive through a puddle. That will narrow down your search I believe the ABS only uses the speedo for the rear and sensors for the front, though. Not a lot to check. Checking the wires and connectors from your front hubs would be prudent.

Note the sensors will read 3-4 mph not moving this is normal. They are in accurate below that speed so they don’t go below. But they should equally go up and down above that speed. Possibly a little faster on the rear if you brake hard or accelerate fast or hit some gravel from a stop. That will cause the speed to jump a bit in the rear

Also if your tire size is not adjusted in the ebtcm to a aftermarket speed the values won’t be accurate to actual speed, this is separate to your speedometer.

 

[99Sierra2500]

In our 2001 Yukon, when it rains or we go through a puddle, the ABS and brake light come on. I crawled around under it the other day and checked wiring and connections and I dont see anything wrong. Next I will use a pressure washer attachment to roll under each area to help pin point where the problem is.

Anyone know of a common problem with these ABS systems and water?

Mine likes to come on in the rain too, I think it is the module getting wet, though I don't know for sure.

 

[zachammer85]

I've heard of abs modules having bad solder connections in the case, it's located driver's side frame rail near the front. A new module is about 300+ dollars to replace or if you can solder good, you can take the original off and repair the connections yourself. This is known to cause the abs and brake light to come on as well. Need to do this on mine soon.

 

[ORVietVet]

I've heard of abs modules having bad solder connections in the case, it's located driver's side frame rail near the front. A new module is about 300+ dollars to replace or if you can solder good, you can take the original off and repair the connections yourself. This is known to cause the abs and brake light to come on as well. Need to do this on mine soon.

THIS^^^^. Especially since it is exposed to the wet weather.

 

[Cadillacmak]

I need to look into this soon, but my other trucks are consuming all my time.