Mitsubishi S11, S12, S13 A/D error (Error 17) resolution

I am trying to gather any information that someone may have on an error 17 displayed on a Mitsubishi S11, S12 or S13 drive. As best I can tell, all of them are the same fundamental design and they all have a single A/D. On the multi axis drives, the A/D is probably just multiplexed. What I'm looking for is, hopefully, any information someone may have that can help me fix the problem. Ideally, this would be an input schematic that leads to the A/D. My guess is that the source of the information is R1A, but it could be a composite of the other sense resistors too that are averaged. Whatever the case, this probably then goes through some filtering, maybe some level shifting and op amps, etc, before it gets fed into the A/D. Even if you don't know electronics but had a similar problem and the tech described the issue to you, that would be of benefit too....