I have a 94 Q45 base w/o TCS and my ABS light is on. I haven't gotten around to pulling the code yet, but I wanted to ask what the common problems with the system are.

The symptoms are as follows:

When I turn the key to "on", the light illuminates.
When I start the car, the light turns off.
I can shift into any gear and the light stays off until I start moving.
As soon as the car moves more than 5 feet, the light illuminates and stays on until the car is turned off.

I'm thinking wheel speed sensor, but after pricing them ($200-$400 new depending on which one ), I'm REALLY hoping someone has had the same problem and it was something stupid, like one of the relays.

I am grateful for any input...

Thanks!

Relay failure usually shows as "stuck on" and the actuator runs continuously, even after the car is turned off. You might check your factory service manual at www.nicoclub.com/FSM/ and try the self diagnostics there to narrow it down.

Heath

Well, I finally got some time to pull the code, and it was a code 9, "Actuator Motor Relay." I just went for the easiest diagnostic step, check the fusible link, and viola! The fusible link had been pulled and was sitting next to it's socket in the power dist. box. I plugged it back in expecting the motor to turn on and geek out, but no! Drove the car, the light stayed off, and tested the system on a patch of gravel and it works perfectly. Hooray for ABS! Now my notification panel is dark while driving... How satisfying!!!

In my haste, I jumped to the conclusion that it was a wheel speed sensor, so I just bought all three from a junkyard in Alabama for $80. At least I have spares in case one does go out...

Unlikely unless curb hit or other abuse, that ABS wheel speed sensor fails.
They are robust compared to newer cost saving versions.

I drive my Q pretty hard, but I'm hoping the ABS will help me avoid the curbs...

Might want to get a relay to have on hand in case that fuse was unplugged in the past for a reason... Sticky relays tend to be intermittent.

Heath