One more theory I will check: I went over all my power and grounding wires, and I notice that I assumed that the CAS should be grounded through the shielded wire that returns to the MS (pin 1). Seems like the MS usually just grounds sensors through itself, and those are usually at 5v max.
Other folks seem to have just grounded the CAS directly to the motor or back to the battery. I'll try that to and see if that makes a difference.
Just throwing stuff at the wall - something will stick
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