ABS Advice

[Mark Eaton]

I am three months into my mk4 build and I am interested in an ABS brake system. It appears that I need a hydraulic modulator device, ECU, and Sensors. I haven't been able to find a complete system for sale anywhere. What I'm not sure of is are all these parts interchangeable ? If I purchase an AC Delco modulator will it work with whatever ECU I find? And what about the sensors? Do all the ECU's recognize all different types of sensors? That seems unlikely.

Finally, What about the splines which the sensors look at. I clearly have them visible on the front but I'm not sure about the rear...

Any input is appreciated.

Mark

[edwardb]

I also posted this in your build thread. Check this post for an explanation of the 2015+ IRS rear ABS sensors. http://www.ffcars.com/forums/4823601-post18.html

[2bking]

This thread on the other Forum has a lot of information that you seek. Up until about 1998 the ABS modulators were stand alone units and didn't need the PCM to communicate a failure because of an internal test function for determining the source of a malfunction. The later ones are still stand alone units except for traction control and error reporting. I used a 99 thru 04 Mustang GT ABS unit without traction control for my module. It works fine and reports a malfunction using a steady light on the dash but can't report the fault code. It is designed to transmit the code to the message system which isn't supported with the Ford Racing PCMs. The pre 99 units would blink the ABS light to report the failure code. I suspect all the later models also report codes to a message system. There are only a few modes of failure and can be tested with an Ohm meter. If the failure is internal to the module, it will need to be replaced so the exact failure isn't important. There are three and four channel units available from various Mustang models and other cars as well.