TAC 50

We have been fighting the same issue for a while on this car. We have been thru several items as far as the following:

Sent all boards (DSP, PMI; etc.) for testing and repair.
Changed 5v power supply and set to 5.1
Checked for AC leakage into my DC power supply
Changed the molex connectors on the DSP card
Changed the governor encoder board.

I get faults 109, 52, and 812.
109 = Encoder Cross Check Error
52 = Tach Fault Warning
812 Positive Torque Limit

It is highly intermittent and will run at times for a week or more. Any help is appreciated.

Have you checked the governor encoder vs the motor encoder. They should be within 5 fpm of each other.

Sounds like a shielding problem. Check that shield wires are only connected at one end and check all grounding. Any radio transmitters close by?