ABS and Brake lights come on
 

I have an issue with an '01 Windstar LX where the ABS and "Brake" lights come on after a few minutes driving. Initially I put it down to the left front ABS sensor being broken, but that was replaced. For a while the lights stayed off, but they're back on with regularity now.

I did some searching on the problem and found that a low brake fluid condition may cause this, but that isn't the case here. I also read how the brake pressure switch on the bottom of the master cylinder could be leaking fluid into the ABS harness causing the light to come on, but there are no leaks in the system - anywhere.

I'd like to know if there's a reliable way to test the individual ABS sensors. I'm guessing one of them is bad, but they all seem intact. Replacing them one by one seems a round-about (and expensive) way to do it, and there must be some other way of checking them.

Anyone have any ideas?

Thanks

I forgot to mention that there are no trouble codes with this problem. My code reader comes back with "No Codes".

Just wondering, does you code reader actually read the ABS "C" codes? Seems like it should log at least 1 code.

I don't know. It's an Actron CP9550 (Pocket Scan Plus) and I don't see anything in the documentation about what kinds of codes it reads. It's not their top-of-the-line model, but I'd think for almost $100 it would be fairly complete.

I guess I'll take it to a parts store and have them read it for comparison.

Nope, that one doesn't do ABS codes. I have an Autel Maxidiag Elite MD802 for 4 System with Data Stream Model Engine, Transmission, ABS and Airbag Code Scanner. basically covers all OBDII makes and models. They run between $300-600 depending if you get a case or not.

Took the car down to someone with the appropriate code reader and he found C1185 (ABS Power Relay Output Circuit Failure) and C1198 (ABS Inlet Valve Coil LF Circuit Failure) codes.

I replaced the LF sensor because it broke when I removed it to change the left strut and drive shaft, so I'm guessing the C1198 is a leftover from that work.

About the C1185 code, does that necessarily mean I need to replace the ABS module?

Here's a good read and may help you with the C1185 code...

ABS Light On - DTC C1185 ABS ECM repair or replacement - Ford Windstar

Nice article. I'll give this a go before considering alternatives.

Thanks!