ABS light issue
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Junior User
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From: Georgia
ABS light issue
My 2002 has recently (in the last two months) started having the ABS light come on intermittantly. I removed and cleaned both front ABS sensors (they were very dirty) and also the rear sensor (not very dirty). It did not correct the issue. What is my next course of action?
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How are the sensor rings on the front rotors ? Caked with dirt or rust build up, or, missing a tooth or more, can cause signals to be inconsistent. Could be the sensor bracket got bent a little from repairs or rocks or something. If the air gap isn't the same on both fronts, the signal will be faulty. It's also possible that a corroded harness connection is blocking a signal.
Dave
Dave
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From: Georgia
The front sensor rings did look a little dirty but I did not clean them. How do you get the sensor gap set and what should the measurement be? Will there be a fault code to point to the problem?
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If the sensor mounting bracket isn't bent, the air gap isn't adjustable as far as I know. Also, the air gap is usually something like .045-.050. Hard to measure with rust and corrosion. The sensor is magnetic, so if the sensor ring is nasty with rust, dirt, or missing teeth, the AC signal will be erratic. There might be a code for signal strength, but unless the sensor fails, it may not be a hard fault code. Yours seems to be still functional to some degree, that's why I suspect sensor ring problem, or, possibly a harness wire/connection issue.
You can check the sensors for signal, but it's not really easy. The wire leads can be checked with an AC voltmeter ( the leads from the sensor itself ), if you can make that connection, and with help, spin the wheel. You need around 5 mph speed equivalent or greater for the sensor to produce a signal. Something just short of 1 v AC, I think is minimum.
Dave
You can check the sensors for signal, but it's not really easy. The wire leads can be checked with an AC voltmeter ( the leads from the sensor itself ), if you can make that connection, and with help, spin the wheel. You need around 5 mph speed equivalent or greater for the sensor to produce a signal. Something just short of 1 v AC, I think is minimum.
Dave
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From: Georgia
I finally had the ABS system scanned for codes and the right front sensor showed up as bad. I bought a new sensor and replaced it. It was obvious what was wrong with it once removed. The wire had fallen off the inner fender and was touching the exhaust manifold where it sustained some melting and damage. I also cleaned the sensor ring before installing the new sensor. A scan the next day did not reveal any ABS codes present. Hopefully this issue is resolved.
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