Replaced wheel bearing assemblies on front with abs sensors. Wiring connectors appear to be ok. But the abs service vehicle soon and trac off lights come on when you put the vehicle in gear. What could be causing this?

Buick Rendezvous Service Traction system and Anti-Lock warning ...

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Jul 15, 2007 - 31 posts - ‎19 authors See Also: Buick Rendezvous FIX Trac Off ABS warning light DTC sensor hub wheel.... For the service traction,ABS,AWD lights it may be a wheel speed sensor (also .... I drive a 2004 Buick Rendezvous with about 120K miles.Missing: atl

Most likely that one of the ABS Wheel Sensors is disconnected or got damaged during repairs that you made. Check connectors for ABS wheel sensors at front brakes. If look ok, you need to check computer codes to know which sensor is damaged and replace sensor.

Very common problem. The MOST LIKELY cause is that you have a front wheel speed sensor that is not working properly. This could be due to a bad front wheel bearing assembly or it could be a wiring problem. GM has had a LOT of problems with the wiring harnesses. A company named "DORMAN" makes a harness repair kit. (See picture below) The Dorman part number is: Part Number: 970-041 The wheel speed sensor itself and the wheel bearing come as a complete "HUB" assembly. The wheel bearing should be checked for looseness and the speed sensor should be tested at the speed sensor connector for AC voltage output when the wheel is spinning. If the bearing or the sensor is bad, then you must replace the hub assembly. If this is the case, I recommend using the "Timken" hub assemblies. They are more expensive, but are much better quality. I have had many problems using the cheaper brands. (See picture below) If the wheel bearing and sensor is OK, then the harness should be replaced. You will have to scan your Antilock Brake System (ABS) module to find out which one is causing the light to come on. As far as cost...it depends on exacltly WHAT it needs and WHO is doing the job. There also may be more than one speed sensor giving you problems. Your best bet is to get it diagnosed and get an estimate of repairs. If they try to sell you a hub assembly, ASK them if they actually TESTED the speed sensor. MOST mechanics out there will just throw a speed sensor (hub assembly) at the problem if they have a speed sensor code, only to find out later that the problem is in the harness. Of course, the customer is the one who ends up paying for their incompetence when this happens.
SPEED SENSOR WIRING HARNESS REPAIR KIT


WHEEL BEARING, SPEED SENSOR AND HUB ASSEMBLY

When they replaced the wheel bearings there are sensors connecting to the hub I would make sure that the sensors are connected and that there is no corrosion on the connectors.

there maybe a short in the ground wires somewhere.or one of the sensors for the brakes needs to be check.

If you replaced the rotors you may have the wrong rotors, or you may have dirty wheel sensors, it is easy to clean them with a tooth brush and brake clean, try this first. The reason is metal brake dust can collect on the sensor and stop the sensor from producing the 2.5 volts DC as it turns, this would be seen as a fault by the computer as a wheel not turning as fast as the rest of the wheels. Hope this helps if you need more information please let me know. And thanks for using fix-ya.

You can test the wheel speed sensors by unhooking the connectors and put ohmeter test leads on the sensor terminals should read around 1100-1600 ohms also the connectors themselves were bad for wires breaking inside the insulation at the connectors from flexing when the wheel is turned back and forth..Note excessive wheel bearing noise from bad bearings have also been known for interferring with clean abs signal also causing abs codes good luck

BAD WHEE BEARING AND PROBABLY THE PLAY FROM THE WHEEL BEARING HAS DAMAGED THE SPEED SENSOR FOR THE ABS

I'm sorry to say that you will need to see a dealer or repair shop so they scan your ABS for trouble codes first and then find your problem.

Are you sure of the lights? If it is Service VEHICLE Soon, in addition to Trac Off and Anti Lock, it is most likely one of the four wheel hub assemblies. These are sealed bearing units that feed a signal to the computer for the ABS brakes and the tire pressure system. I had one go out intermittently (seemed to be aggrivated by humidity/moisture). I had it replaced, and another one is going out. It seems like they are a bit prone to failure. My Century has 101K, and I experienced the first one around 75K miles. Unfortunately, to tell which one is failing requires a scan tool above and beyond the simple one that most parts stores use. BTW, there was a problem that was fixed just prior to 2002 that was caused by the signal wires going to the left front wheel hub being worn through and shorting. I believe this problem was fixed by 2002.