Aftermarket head unit will not turn off

volvo850black · Post by **volvo850black** » 19 Jul 2012, 01:40

I installed an after market headunit in my 94 850 NA. I bought the wiring harness. I hooked everything up and it works great except it doesn't turn off when the car is turned off. Afraid my son who drives the car much of the time will leave it on and kill the battery. There were two extra wires on the harness that did not have a companion on the unit. One was orange the other was blue. Does anyone know what can be done to remedy this issue?

Post by **schmidm90** » 19 Jul 2012, 10:36

When I installed mine, the blue wire is for a power antenna and the orange one is a dimmer(not 100% sure). To me it sounds like one of the wires got crossed. There should be a red power wire and a yellow one that only gets power when the key is on. If the radio does not get the signal from the yellow wire that the car is off, it wont shut off.

http://imageshack.us/f/233/v70radiosk3.jpg/ is a diagram for the wiring for a V70 which might help to eliminate the problem.

volvo850black · Post by **volvo850black** » 19 Jul 2012, 14:51

I hooked up both of the yellow and red and even switched therm to be sure still won't turn off. Guess he better remember to turn it off or get stranded.

db130 · Post by **db130** » 19 Jul 2012, 15:56

sounds like the switched 12V wire and the constant 12V wire may have been switched during the install?

If you have a factory deck installed, does it switch off when the engine is shut off?

Post by **Matty Moo** » 19 Jul 2012, 22:14

That's what I was thinking, as far as the constant and switched getting reversed.

When I hooked up the Metra harness to my last Pioneer unit, each harness was an exact match color for color between the pioneer harness and the Metra.

volvo850black · Post by **volvo850black** » 19 Jul 2012, 23:36

This is a metra harness and I have tried switching the power wires no change and yes the factory unit did turn off with the ignition. I have installed wired and audio put systems in dozens of cars without this much trouble.

Post by **Matty Moo** » 20 Jul 2012, 20:23

That doesn't make sense. What brand is the head unit?

Post by **BEJinFbk** » 20 Jul 2012, 22:14

Make and model of that HU would be helpful.