!999 Lumina ABS Light

So, if the mechanic replaced the faulty sensor with the good one, you should
re-connect the fuse to test the system. If the ABS light still lit, that
means the problem has not been solved.

I would try to get sensors resistance reading at each wheel and if possible
with harness as far upstream as possible. I have seen ABS's harness
failure at rear trailing arm where it exposed to water from the wheel well,
there you will find two ABS connectors going into one harness. So make sure
it is clean and well sealed. Common ABS sensor failure is at front wheel.
Typical the internal resistance I have seen is around 1100 - 1300 ohms. My
failed sensor read as high as 12,000 ohms at time of failure and as low as
2,000 ohms when it dried up over a month or so. Small resistance reading
such as 100-200 ohms does not necessary indicates sensor failure.

Hope this help!

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Still ABS sensors or wires. Bring to dealer or have someone that is good in
electronics to check for internal resistance of ABS sensors to ABS control
module. If you don't want to spend any money on right now, remove ABS fuse.
If you decide to remove the fuse, your ABS light will remain lit. I had
similar problem not to identify your car problem here since it involve more
than sensors. However, ABS sensors failure is a common problem to most ABS
system failure. Some model has traction control that also tie with ABS
system so that mean if the traction control module or system has a problem,
it could also trigger ABS light. All ABS sensor should have similar
internal resistance. By checking internal resistance and compare the value
to each wheel, I was able to track to one specific ABS wheel sensor. Front
wheel sensor is more diff. to replace that back wheel.

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