Head unit doesn't turn off, comes on even when car off and no key in ignition

[Accipiter 10+ year member]

OK, I have a Pioneer DEHP-9800BT; works great. Then this morning my Service Engine Soon light comes on (not the check engine light). This may be connected to the problem I'm experiencing, I'm not sure, but I thought I'd mention it. So here's the problem:

Now normally my head unit turns off when I open the car door after turning the car off. In addition, the key needs to at least be in the ignition and one click to the right before the head unit turns on. This morning all of a sudden the head unit started turning on as soon as I put the face plate on it. Without the key being even in the ignition....Which is odd enough, but then when I drive around for a while or whatever, park, turn the car off, and open the door, the head unit stays on still. The only way to get it to turn off is by hitting the eject button on the cd player and then taking the face plate off when it descends to eject the cd.

Any idea as to what's going on here?

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[Accipiter 10+ year member]

ok wtf.....it just started turning off when I open the door again..........what the hell is going on here?

 

[keep_hope_alive Premium Member]

A bad or stuck door trigger switch is a possibility.

That would cause the car to think the door was closed even when you opened it. Or the control module that controls the system.