I have an intermittent ABS issue, The ABS INOP light will go on without even touching the brake pedal. After driving about 3 miles, the light just comes on. Second question, I read where a failed brake light bulb would trigger the ABS INOP light. The car has 2 taillights on each side (4 total) only the inside ones (one on each side) light up when the pedal is pressed, Is that correct or is all 4 suppose to light up?

 

The problem is with the center lights, if the lamps are not working it will bring up the ABS lamp. The best thing is to get the ABS scanned so you will know why it is complaining. Also, if all the tires are not the same diameter the ABS will come on.

 

The third brake light is working good. I bet it's the tire size issue, The rear tires have half the tread depth as the front ones. I know we're only talking a few 32/nds but that makes sense. I guess I've gotta quit wearing down the back tres.

 

Can someone answer my second question, Does the car have 2 brake lights or 4?

 

Tire wear will not cause the issue you are seeing. If the tires are completely different sizes, that is what can cause your issue. But the only way to know for certain what is at fault, is to scan your ABS computer for codes.

The tires on our cars are all the same size from the factory. If you replace the rear tires with ones that are taller, (say 25 inches) and leave the factory size on front (say 23 inches) that much of a size mismatch can cause wierd ABS issues. Note, I am not certain what the height of stock tires are, the sizes I used are just for an example.

 

I found my ABS problem. some wise member, sorry I don't remember the post, suggested that one of the spark plug wires was too close (wiretied togethor) to the ABS wiring harness. The voltage from the plug wire was tripping the sensor. Simply moved the wires, no more light problem.

 

Wow. That is one seriously wierd thing. How did you ever diagnose it?

 

I read it on this forum, just can't find it again to give credit where it's due