Car Electronics Questions? Ask an Electronics Expert for Answers ASAP
Hi, The red wire is your switched radio wire. If your radio doesn't turn off with the car (even after you open the door- which is how most work), then you don't have your red wire interfaced properly- you have it connected to a constantly live source. Who interfaced the wiring from the Pioneer to your Hummer?
I'm assuming you tied both red and yellow wires to the Orange 12V in the Hummer's wiring? If so, that's a constant live wire- that's why your radio doesn't shut off. You need to 5 wire a relay to the ignition wire (Orange at IGNITION SWITCH harness). Then your red connects there so the radio shuts off with the car.
Do you need any further assistance with this?