ABS Problem
 

1998 A4q, 2.8 30v. Manual trans. 150k miles. Original owner.

PROBLEM:
My diagnostic tool can't communicate with the ABS unit. We have found that there is no juice to fuses S13 and S18. Can anyone tell me what those fuses are for and maybe why there is no juice to them?

What led up to this? My brake and abs lights came on. Diagnostic was able to read a 00283 (left front sensor) code. We replaced the sensor.

Now, diagnostic can't or won't communicate with the abs unit - brake and abs lights continue to flash on the instrument panel.

Any ideas?

Thank you!!

It's very possible your ABS unit is now faulty and requires rebuilding and/or replacement. This is extremely common on the B5 A4. There are multiple sites which will perform this service for a fee. I personally used CHEAP Bosch 5.3 ABS REPAIR VW Passat Audi A4 A6 A8 S4 , and others have had good luck with http://www.modulemaster.com