Thread: ABS and Trac Off lights

Originally Posted by scottydoggs

don't buy cheap hubs, only buy a name brand with a warranty and cost at least 100 bucks each, buy cheap crap and you will be buying another one soon.

100 bucks is cheap enough.

Edit: Don't worry too much about me, I'm not stupid enough to buy cheap hubs.

I'm fighting this battle now. RF hub bearing replaced about 6 months ago. ABS and TRAC OFF lights come on and stay on entire time ignition is on, also steering is very stiff at low speeds. Replaced LF hub bearing and thought I nailed the problem when it came out in two halves, but lights are still on. Just replaced all 4 struts and didn;t see anything unusual with bearings or wiring. Ideally I would like to run a continuity test on each wheel circuit from the EBCM connector but I can't find a pin-out diagram for the connector anywhere. Found Cheap ABS website and he will repair and guarantee the EBCM for $99 plus shipping, so am thinking of rolling the dice on the EBCM.

Had it scanned at Tire Discounters and the guy said he couldn't pull any codes with his ABS scanner, so that, combined with the fact that steering is affected would lead me to believe the EBCM is bad....I have not had any steering symptoms when just a wheel sensor was bad, and if that was the case, they should have been able to pull a code on it. Can't wait to spend ANOTHER $100 on this car.....

Anybody have a wiring diagram at the EBCM connector to check the wheel circuits???

Module Masters are good folks and would recommend I used them for the Suburban EBCM a few years ago. They are at $160 to rebuild this Bosch 5.4 unit, Matt at Cheap ABS is at $100. This guy is an electronics engineer and claims his process is better than MM, we will see, he is recommended on the VW and Audi forums.

Update: Matt from Cheap-ABS emails to tell me there is nothing wrong with the module so there is no charge except for shipping. I could not find the pin out diagram for the Bosch 5.4 but I was able to find resistance values for the wheel speed sensors. So using an ohmmeter I was able to determine that the LR wheel sensor was inop, so replaced that hub bearing last night. Problem solved.

Anyone got a site or thread on how to test your wheel bearings bc the abs and tc lights are on go once in a great while
2001 gtp

I heard somewhere you can put a volt meter on it and tell the resistance and see if they were bad.

Originally Posted by kawasakidrivinghick

Anyone got a site or thread on how to test your wheel bearings bc the abs and tc lights are on go once in a great while
2001 gtp

If you can't get easy access to a scanner, do a visual check on the wiring to the sensors, unplug, clean and replace the wiring connector at each sensor. My lights were coming on every once in a while and then eventually would trip on as soon as I turned the steering wheel to the right even when parked. Always could clear the light by turning off and then restarting the car.Turned out to be just a momentary bad connection at the right front wheel that would cause signal dropout from that wheel's sensor. If the lights come on intermittently every one in a while and then can be reset off by shutting off and then turning the ignition back on, I would put my money on bad wiring before a bad wheel sensor any time. Of course it could be wiring further up the path from the wheel sensors as well, but I would start there first, especially at the front where the wiring is subject to a lot of movement when steering. Wiring issues are far more common than module issues in almost all problem situations involving automotive electrical and electronic systems.

I found out how to check the speed sensors in the wheel bearings. Unplug the sensor wire at the wheel bearing, and using a multimeter set for ohms, measure the resistance between the two contacts on the hub bearing side of the connector. Resistance should read between 850-1350 ohms. When the sensor goes bad the resistance will read as infinity, like an open circuit.

An easier way to do this would be to check the resistance right at the EBCM connector, that way you can check the whole circuit to each wheel, both the wiring and the speed sensor, but I could not find a pinout diagram for the connector to see which pins were the wheel sensors.

As was said, the scanner is only as good as the guy using it. I had mine scanned and the guy said he couldn't pull any codes, leading me to believe the EBCM was bad, but that wasn't the case.

when u scan it what if nothing shows up on the scanner bc nothing does on mine and both my lights are on

Originally Posted by brandonl2000

You either have bad wheel speed sensors, bad wiring, or the EBCM is bad. There are trillions of threads with this same topic.

My advice: get it scanned, that way you don't waste your money throwing parts at an unclear target.