Pretty simple solution is a relay that uses the 10.5v door switch to close a 12v circuit to the CompuStar.

Installers may have been lazy or too busy to want to deal with it that day. Should have been an easy workaround for them.

Here is a basic version of what I'm talking about: Amazon.com: 12 VDC Automotive Relay SPDT 30/40A: Electronics

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