Originally Posted by kc1
not checked voltage yet on the red or yellow yet. I will go do that now. trigger wire is blue on each (i.e. amp and fusion).
I think the "plastic units" = "circuit breakers" installed on the panel under the steering wheel. I removed the frame of the panel so I can access without sticking my head up under the dash. looks like wiring to the different circuits is different or I was considering trying to remove the connectors going to the circuit breaker labeled "stereo" and reconnecting to the accessory 1 or accessory 2.
If you're not familiar with how to use a multi-meter, you need to become familiar. You should also become familiar with some electrical terminology and theory- it will make any electrical troubleshooting far easier and accurate.
You can use a test light, too (the kind with a bulb). DO NOT use this for any circuits that involve the senders and ECM, only supply voltages like the red and yellow wires or testing for a ground.