The ABS module is at one end of the CAN bus, the instrument pack is at the other end. Each has a 120 ohm terminator resistor, which together gives the 60 ohm value the CAN bus needs to work properly. A fault on the ABS module could disrupt the whole CAN bus - whether that is your problem here is anyone's guess. One simple test you can do is measure the resistance of the CAN bus at the OBD port with the ignition off to see if it is close to that 60 ohm value and take it from there.

 

Dibbit which pin in the OBD port is that? my Chromebook won't play nice with the diagrams here

 

By far the most common cause of the random ABS/ASC/TRAC warning lamps is cracked solder joints for the ABS pump motor electrical connector pins on the circuit board of the ABS module. This fault triggers DTC C1095, but your scan tool must be able to read Chassis (C-prefix) codes to see it. Most generic OBDII scanners can only read the Powertrain (P-prefix) codes.

But in addition to the cracked solder joints for the pump motor connector, in every Ate ABS module I have opened I have found several starved, cold or cracked solder joints for other components and the large multi-pin connector through which the wheel speed sensor and CAN signals pass. Faults with the CAN typically trigger Network DTCs (U-prefix), so again, you would need a scan tool capable of reading those to see what the computer modules could tell you to aid your diagnosis.

dibbit's advice to measure the resistance on the CAN network is a good idea. You can measure this at the Data Link Connector pins 6 (Yellow wire) and 14 (Green wire).

It would be rare for an ABS problem to cause rough running, but if the CAN is malfunctioning, all bets are off.

Cheers,

Don

 

thanks Don! i'll see what my Can resistance is. i have an Auto Enginuity unit on order so i'll be able to see those other codes.

 

If the Auto Enginuity system you have ordered is like my old one, be sure your system comes with the Jaguar Enhanced Interface software or you won't have full functionality..

Cheers,

Don

 

do a compression check for the hell of it. I dropped an intake valve seat and the symptoms sound a lot like what my issue was. Couldn’t hurt

 

Don, i doubt that it has the enhanced software. i already expected to have to get it.

 

have not done that yet. but as you said it couldn't hurt. your car was bi-polar too with a valve seat dropped? that's not normal. once a seat drops they normally just run like crap unless
the seat comes apart and trashes an engine.......