Rather off topic question on an Audi

[Cloudsurfer]

This is off topic....but I figure some of the gearhead, engineer types here might have some insight on this before I go scour the Audi forums.

My father has a 2000 A6 4.2 (the V8 quattro). 60k and car is in amazing shape. Recently, both the ABS and Brake warnings have been on and off. Flushed the fluid for him, checked the pads and sensors, and everything is fine. So he brings it in for diagnosis, dealer claims

"Code 01203 loss of comm between ABS module and instrument cluster. Need to replace ABS module." Part is $750, and two hours of labor.

Now, if it really is a loss of comm, who is to say the problem lies in the ABS module and not the cluster itself? Or for that matter, could it be something stupid like a cable?

I'd love some insight if anyone has any.

Thanks

Patrick