How to tell which wheel bearing sensor is bad?

[claimed4all]

Is there an easy way to tell which wheel bearing sensor is sending a bad signal without a scanner? If I drive within a hlaf mile or so I will here my ABS power once or twice without touching the brakes and then the system will fault out giving me NO TRAC, ABS and SERVICE VEHICLE SOON lights. For the time being I have just pulled the ABS fuse so the system doesn't have a chance to fault out every time I drive. So I want to replace the bearing, just now sure which or where to start. I do not have an ABS scanner.

[Tech II]

Without a scanner to read a code, you don't know which wheel is at fault.....My Autozone in town has a scanner that reads ABS codes....

9 out of 10 times, it is the sensor.....but could be a harness, EBCM, relay, etc.

First thing to do is a visual inspection of the harnesses to the sensor of each wheel......

Two things you can check without a scan tool.....resistance and A/C output......resistance is just a resistance check of the sensor harness with an ohm meter.....for A/C voltage check, you measure voltage of the sensor while rotating the wheel by hand.....

Unfortunately, I don't have the specs at hand....perhaps someone can post them for you....

[Blue Bowtie]

What year LeSabre? The year will generally indicates which ABS system is installed, and the diagnosis is different for the different systems.

However, a quick/dirty test of the AC voltage generated by each wheel speed sensor can be a hint. Connect a voltmeter to the speed sensor directly at the wheel if possible, or as close as possible (some include a pigtail in the harness) and turn the wheel at about 60 RPM while reading the meter. Most rear sensors should produce at least 0.6 VAC and most from sensors should produce at least 0.9 VAC. As stated, those vary from system to system, but if you discover a sensor is producing no voltage you have a suspect sensor.

[claimed4all]

Originally Posted by Blue Bowtie

What year LeSabre? The year will generally indicates which ABS system is installed, and the diagnosis is different for the different systems.

However, a quick/dirty test of the AC voltage generated by each wheel speed sensor can be a hint. Connect a voltmeter to the speed sensor directly at the wheel if possible, or as close as possible (some include a pigtail in the harness) and turn the wheel at about 60 RPM while reading the meter. Most rear sensors should produce at least 0.6 VAC and most from sensors should produce at least 0.9 VAC. As stated, those vary from system to system, but if you discover a sensor is producing no voltage you have a suspect sensor.

Its a 2002. The problem it becoming more intermittent now though. Lights won't come on at all for a few days and then they come on every time I drive it for the next few.

[gmtech1]

As stated eariler, need to see what code is stored.

[Jrs3800]

If the ABS and TRAC OFF lights came on as soon as you started the car, Then I would say there was an issue with the EBTCM/Pump, But with what you described it does sound a lot like a wheel speed sensor...

Like stated by everyone its going be be much easier to have the ABS System scanned to see what codes you have... This could point you in the right direction to a repair...

I had a friend hook a Snap On to my car to scan for ABS codes when I was having issues... Pointed me directly to the EBTCM/Pump on my car... Better than wasting time and money....lol

[claimed4all]

Originally Posted by Jrs3800

If the ABS and TRAC OFF lights came on as soon as you started the car, Then I would say there was an issue with the EBTCM/Pump, But with what you described it does sound a lot like a wheel speed sensor...

Like stated by everyone its going be be much easier to have the ABS System scanned to see what codes you have... This could point you in the right direction to a repair...

I had a friend hook a Snap On to my car to scan for ABS codes when I was having issues... Pointed me directly to the EBTCM/Pump on my car... Better than wasting time and money....lol

When I have time one day I will swing into a shop and see if they can plug it in for me. Now does the car store the ABS info? (If the light comes on and then goes off, is the information stored)

[gmtech1]

If the light came on, there should be a code stored. Even if the light is not on at the time the codes are scanned.

[HotZ28]

If there is not a current CEL stored, it may be pending, or history. You need someone who is familiar with how to operate a full function scanner.