Hey everyone I just followed wrathernauts guide to install a new jvc kw-v51bt headunit into my 03 g35 coupe to replace a poorly installed old hu.
After the install the headunit started right up and worked great! But the problems started when I went to turn off the car... the radio didn't turn off.
Naturally I rechecked all of my wiring connections and they are all 100% correct.
So I got out the voltmeter and tested the acc/ignition wires as well as the yellow power constant wires. I checked the ground wires as well and it's all good all around.
I'm thinking that it's my car not turning off the acc wire to the radio (and elsewhere possibly) doesn't anyone have any idea what's going on? I'd like to not have to wire in a switch to turn the radio off.
Thanks in advance

 

Answered in the PM as well, but...

It's most likely you've got the switched power for the radio connected to constant power. If you disconnect the red wire on the radio side and it's still powered up from the constant power, it's a bad headunit.

 

That's what I was thinking so I triple checked that all wires were exactly where they needed to be. And then I used my voltmeter and tested every connection down to the main radio harness from the factory and the car is not turning that red wire off with the key. The headunit seems to function exactly as it should. It's the car not cutting the power when the key is turned off that's why I came here looking for answers

 

And that's why I was guessing that you've got the red wire connected to something else that has constant power further up the line.