ABS acting up

ionmaker · June 18, 2003

My ABS started activating under 5MPH ANyone else have this and what should be done to fix it ? Thanks.

Jersey Tahoe LT · June 18, 2003

There is a TSB out for this. I doctored this one up to delete all other vehicles as I have friends with Tahoes just like mine. It is the same for a lot of them. I tried it myself but couldn't because I don't feel like taking the hub and bearings off. Here it is.

TSB #02-05-25-006A - (11/26/2002) and there's another that haven't been able to find text: 99046B SERVICE BRAKES, HYDRAULIC: ANTILOCK

Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting Surface) #02-05-25-006A - (11/26/2002)

Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting Surface)

1995-2000 Chevrolet Suburban, Tahoe (Old Style)

This bulletin is being revised to change model information. Please discard Corporate Bulletin Number 02-05-25-006 (Section 05 -- Brakes).

-Condition

Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph). Upon investigation, the technician will find no DTCs set.

-Cause

The cause of this condition may be an increased air gap between the wheel speed sensor and the hub reluctor ring due to rust and debris built up on the sensor-mounting surface.

-Correction

Measure AC voltage and clean wheel speed sensor mounting surfaces.

Raise the vehicle on a hoist.

Disconnect both the front wheel speed sensor harness connectors.

Place a DVM across the terminals of each sensor connector.

Rotate the wheel with hand speed and measure the ACmV's. The reading should be at least 350 ACmV's.

If the reading is between 200 and 350 ACmV's, remove the wheel, caliper and rotor in order to gain access to the speed sensor.

Remove the wheel speed sensor and plug the hole to prevent debris from falling into the hub during service.

Clean the speed sensor-mounting surface on the hub to remove rust and corrosion.

-Important

Make sure that the sensor sits flat on the hub. If the sensor flange is distorted, replace the sensor.

Apply a thin layer of bearing grease to the hub surface prior to sensor installation.

Like I said there are quite a few other vehicles this pertains to. I called the dealer and he said about $140 to $160 for it to be done. He said this fits it to a TEE.

Later,

Brandon

cxs287 · June 27, 2003

I have a 2000 Silverado and went thru the same problem. Dealers are no help on this, I went to a private garage that troubleshooted the problem and replaced the entire wheel bearing assembly, since the sensor was part of it and the total cost was $250 installed. Hope this helps.

Jersey Tahoe LT · June 27, 2003

I would say try the TSB first. That is a good price for the Bearing assemblys. But I know that on my Hoe the sensor is in the Hub itself. And I know that it would be $900 at the Stealer. Maybe it is the same as yours. If so that is a great price.

Later,

Brandon

toddgotfish · June 28, 2003

hub bearing assembly guarunteed

got mine at a local salvage yard for 75.00

but i know a guy on ebay that has them for less than 30.00 and you can do it in less than an hour.if you need help just e-mail me

Thanks

Todd

30cal4me · June 28, 2003

ABS started kicking in at about 12 km/h. This happened about 3 months out of warranty. Front left hub and harness had to be replaced at a cost of $550. CDN.

ekarjala · February 22, 2005

By way of more recent follow up, I recently experienced this with my 2002 Tahoe. The dealer was able to clean one sensor, but broke the other one when removing it and it cost me $158 for parts and $150 for labor to have this resovled.

Big_Jersey_Hoe · February 22, 2005

OK. I am Jersey Tahoe as above. I found that the TSB doesn't really fix it. You will have to take a Volt Meter andcheck your left and front ABS sensors. I would say you should replace the Hub and Sensor as the sensor needs a specific clearance and if it is out a little bit it wont work properly. I found a guy where I was able to get both Right and Left Hubs shipped to my house for $400. That is almost half price. If you want I can send you the info. Now just remember that when you check the voltage that you need to unplug the battery. IF you don't you can short out the sensors and or the computer for the ABS.

Later,

Brandon

camaronut · February 22, 2005

My 01 Sierra 4x4 did the same thing. I took the front speed sensors out and cleaned the faces myself, then reinstalled. This worked for me, but the wheel bearing could be worn and be out of tolerance.

I'd try cleaning them first, then see what happens....