ZF Marine Micro-Commander Problem

[stormsurf]

Hey guys and gals.
I have Mather electronic shift and throttle control head that's wired to a 91102 actuator. My port throttle works but won't shift the transmission. It's "plug and play", so I swapped the port and starboard wire harnesses and found that the problem switched to the other side. Bad control head, right? Nope. I ordered a brand new one and have the same problem. Any guesses as what the heck is going on? Thanks a million. I'm losing charters by the minute.

BP

[Chief Engineer]

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