Hello there!
I got my car stereo (pioneer 2250BT) out for a display replacement, after changing it and confirming it's back to live (in a bench) I was about to put it back in the car and while main power harness connected, the radio chassis touched a metal part of the car causing a spark, that made me think something was wrong..
Turned the key to accessories, waited for the radio to turn on, and nothing happened.
Turned the key out, took my multimeter and found there is 7~8 Volts between the stereo metal chassis and my car chassis while no key is in the car (meaning there is a short in the always-positive cable?)... Unplugged the stereo and here I am : )
So, some questions came..
Is it normal to have a positive stereo metal chassis when it's not grounded yet? If so..
1. Should I connect the black ground cable from the harness to a better ground?
2. Should I put a wire between the car chassis and stereo chassis
If it's not normal..
What should I check? at least to me, it looks like the issue is in the car since the stereo works fine in the bench..
Any suggestion is appreciated.
Thank you!
my multimeter and found there is 7~8 Volts between the stereo metal chassis and my car chassis
ok... back up.
which one is more positive? where did you have the negative and positive probes?
Hi @MountainManJoe,
Positive probe is in radio chassis, negative in a mount plate inside the car (that the radio mount will touch when fully installed).
I will take some pictures when I'm back at home : )
Posted by: @mmj
which one is more positive?
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Response: Radio chassis (which I would expect to be ground)
then your car is fine and the stereo is defective. There should not be any positive voltage on the housing.
It may work fine on the bench, because the housing isn't connected to ground, but that doesn't mean anything.