'95 Chev Tahoe ABS wheel speed sensors
Question:
Thanks to all – very useful information!
“Jacko” wrote: Problem is that they tell me that I need the complete hub with sensor for C$350+ !! They also did not clean sensor or check it’s ground, so it is possible sensor is OK. However, if I could get just the sensor then replacing it is no big deal, but I need to find a part number and source. You description of your problem may indicate what is currently a pretty common problem with the front wheel speed sensors on the GM trucks. One of the wheel speeds sensor signals drops out at a low speed and you get ABS activation even when you aren’t on a slippery surface. No ABS lights appear. There is a TSB on this problem. I’ll include the body of it below…perhaps this will fix your problem. Note that it may fix it without replacing the sensor..which obviously is good for the old wallet. 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) 1999-2000 Cadillac Escalade 1995-1999 Chevrolet Silverado (Old Style) 1995-2000 Chevrolet Suburban, Tahoe (Old Style) 1995-2003 Chevrolet Astro Van, Blazer, S10 1995-1999 GMC Sierra (Old Style) 1995-2000 GMC Yukon, Yukon XL (Old Style) 1995-2001 GMC Envoy, Jimmy 1995-2003 GMC Safari Van, Sonoma 1995-2001 Oldsmobile Bravada 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. 1.. Raise the vehicle on a hoist. 2.. Disconnect both the front wheel speed sensor harness connectors. 3.. Place a DVM across the terminals of each sensor connector. 4.. Rotate the wheel with hand speed and measure the ACmV’s. The reading should be at least 350 ACmV’s. 5.. 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. 6.. Remove the wheel speed sensor and plug the hole to prevent debris from falling into the hub during service. 7.. 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. 8.. Apply a thin layer of bearing grease to the hub surface prior to sensor installation. 9.. Install either the original sensor or a new one in the hub and secure the sensor. Ensure that the sensor is seated flush against the hub. 10.. Install the rotor, the caliper and the wheel. 11.. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel by hand. The voltage should now read at least 350 ACmV’s. Ian
Response:
I found this link on the Web on how to fix Wheel Speed Sensors 
http://www.careersnet.org/automotive/Vale%20HS/auto%20info/Auntie%20L… rama.ppt Jack O
Not offhand, no. Were you getting a message from the ABS control module that this particular sensor was shot? No – There was no message that I noticed – Maybe a light that I did not recognise, but not sure. Indication was fast pulsing when brake pedal was lightly applied – went away if brakes were put on hard. Dealer checked it and found that one sensor appeared faulty – however, I have checked it and sensor shows a resistance. Jack O
Response:
It’s a Halleffect device, therefore no resistance. There is a semiconductor in there. Yes, the part is available and yes it can be replaced. You’d be pretty screwed if they made em’ so they couldn’t be fixed! I took the old sensor out – I checked for open circuit, but there is resistance there – Anyone know what the resistance of the wheel sensor should be (‘95 Chev Tahoe 4×4)? Jack O
Response:
Oh I forgot to add that there is a resistor there, but just for the ECM or PCM to see that there is an electrical connection to the sensor.
It’s a Halleffect device, therefore no resistance. There is a semiconductor in there. Yes, the part is available and yes it can be replaced. You’d be pretty screwed if they made em’ so they couldn’t be fixed! I took the old sensor out – I checked for open circuit, but there is resistance there – Anyone know what the resistance of the wheel sensor should be (‘95 Chev Tahoe 4×4)? Jack O
Response:
Not offhand, no. Were you getting a message from the ABS control module that this particular sensor was shot? No – There was no message that I noticed – Maybe a light that I did not recognise, but not sure. Indication was fast pulsing when brake pedal was lightly applied – went away if brakes were put on hard. Dealer checked it and found that one sensor appeared faulty – however, I have checked it and sensor shows a resistance. Jack O
Jack, The majority of sensors show resistance, that’s the way most of them Anywho, if the dealer ran a diagnostic scan on it and found the sensor to be bad, put your DMM away and just replace it. Regards, Doc
Response:
“”Doc”" wrote Jack, The majority of sensors show resistance, that’s the way most of them Anywho, if the dealer ran a diagnostic scan on it and found the sensor to be bad, put your DMM away and just replace it.
Problem is that they tell me that I need the complete hub with sensor for C$350+ !! They also did not clean sensor or check it’s ground, so it is possible sensor is OK. However, if I could get just the sensor then replacing it is no big deal, but I need to find a part number and source.
Response:
“”Doc”" wrote Jack, The majority of sensors show resistance, that’s the way most of them measuring. Anywho, if the dealer ran a diagnostic scan on it and found the sensor to be bad, put your DMM away and just replace it. Problem is that they tell me that I need the complete hub with sensor for C$350+ !! They also did not clean sensor or check it’s ground, so it is possible sensor is OK. However, if I could get just the sensor then replacing it is no big deal, but I need to find a part number and source.
Ouch! Try www.gmpartsdirect.com Regards, Doc
Response:
“Jacko” wrote: Problem is that they tell me that I need the complete hub with sensor for C$350+ !! They also did not clean sensor or check it’s ground, so it is possible sensor is OK. However, if I could get just the sensor then replacing it is no big deal, but I need to find a part number and source.
Your description of your problem may indicate what is currently a pretty common problem with the front wheel speed sensors on the GM trucks. One of the wheel speeds sensor signals drops out at a low speed and you get ABS activation even when you aren’t on a slippery surface. No ABS lights appear. There is a TSB on this problem. I’ll include the body of it below…perhaps this will fix your problem. Note that it may fix it without replacing the sensor..which obviously is good for the old wallet. 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) 1999-2000 Cadillac Escalade 1995-1999 Chevrolet Silverado (Old Style) 1995-2000 Chevrolet Suburban, Tahoe (Old Style) 1995-2003 Chevrolet Astro Van, Blazer, S10 1995-1999 GMC Sierra (Old Style) 1995-2000 GMC Yukon, Yukon XL (Old Style) 1995-2001 GMC Envoy, Jimmy 1995-2003 GMC Safari Van, Sonoma 1995-2001 Oldsmobile Bravada 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. 1.. Raise the vehicle on a hoist. 2.. Disconnect both the front wheel speed sensor harness connectors. 3.. Place a DVM across the terminals of each sensor connector. 4.. Rotate the wheel with hand speed and measure the ACmV’s. The reading should be at least 350 ACmV’s. 5.. 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. 6.. Remove the wheel speed sensor and plug the hole to prevent debris from falling into the hub during service. 7.. 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. 8.. Apply a thin layer of bearing grease to the hub surface prior to sensor installation. 9.. Install either the original sensor or a new one in the hub and secure the sensor. Ensure that the sensor is seated flush against the hub. 10.. Install the rotor, the caliper and the wheel. 11.. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel by hand. The voltage should now read at least 350 ACmV’s. Ian
Response:
Yes, the part is available and yes it can be replaced. You’d be pretty screwed if they made em’ so they couldn’t be fixed! I took the old sensor out – I checked for open circuit, but there is resistance there – Anyone know what the resistance of the wheel sensor should be (‘95 Chev Tahoe 4×4)? Jack O
Not offhand, no. Were you getting a message from the ABS control module that this particular sensor was shot? Regards, Doc
Response:
Not offhand, no. Were you getting a message from the ABS control module that this particular sensor was shot?
No – There was no message that I noticed – Maybe a light that I did not recognise, but not sure. Indication was fast pulsing when brake pedal was lightly applied – went away if brakes were put on hard. Dealer checked it and found that one sensor appeared faulty – however, I have checked it and sensor shows a resistance. Jack O
Response:
Does anyone know if it is possible to change one of the front wheel ABS speed sensors on a ‘95 Chev Tahoe 4X4? Is this part available from GM? Jack O
Response:
Does anyone know if it is possible to change one of the front wheel ABS speed sensors on a ‘95 Chev Tahoe 4X4? Is this part available from GM? Jack O
Yes, the part is available and yes it can be replaced. You’d be pretty screwed if they made em’ so they couldn’t be fixed! g Doc
Response:
Does anyone know if it is possible to change one of the front wheel ABS speed sensors on a ‘95 Chev Tahoe 4X4? Is this part available from GM? Jack O Yes, the part is available and yes it can be replaced. You’d be pretty screwed if they made em’ so they couldn’t be fixed! g
Doc, Do have a part number or some other reference? I was told that I had to buy the complete wheelhub – Cost about C$350! Jack O
Response:
Yes, the part is available and yes it can be replaced. You’d be pretty screwed if they made em’ so they couldn’t be fixed!
I took the old sensor out – I checked for open circuit, but there is resistance there – Anyone know what the resistance of the wheel sensor should be (‘95 Chev Tahoe 4×4)? Jack O
