You shouldn't be looking for anything until a dealership scans your system with the correct serial reader/diagnostic tool. Odds are not in favor of an independent mechanic having the tool.

Warning: Dealerships usually charge a shop rate of $80-100 for a 1-hour minimum just to scan your system and report codes back to you.

Thanks will, I work with the son of the garage owner... They use the latest snap-on scanner and do a lot of diagnostic work. I understand the low probability of the module being bad. I think your insight to the inability to test the valves in the pump unit is probably the key. Nothing like experience to help in diagnosing a problem. I'll talk to the garage tomorrow to see if they are able to test the gate valves. Thanks again for your help - thats why I always check here!!!