My 2007 g35x sedan with nav has been having issues with the head unit (or so I thought), specifically the music box, compact flash, and in dash cd player do not work. Inserting known a good cd into it and hitting the disc aux button only cycles through the aux input and trunk cd changer (both of which work perfectly). Same with compact flash cards. Using the voice command "compact flash play" it says no compact flash card. The voice command "music box play" freezes on the voice command screen and stays there until you press another button. So I decided to get an OEM head unit (the unit behind the climate/radio controls) and replace mine, which I did, and it does the exact same thing. Did I just get unlucky and this unit has the same issue as mine, or am I missing something else that would be broken? Thanks

 

You went the logical route and nothing changed. Here's what I would do in your situation: Find somebody that has the same features on their G that are known to work, and is willing to help out, and start swapping sections until you figure out what solves the problem. The same way we swap a known good part in for a suspected bad part, just without buying a bunch of stuff.

 

Luckily the pull a part near me recently got an 07 with nav, which is where I got the head unit from. Getting parts shouldn't be an issue, it's knowing what part(s) I should even try to replace. I'm just stumped at what else could cause this issue. My next guess would be something with the wiring harness but I didn't notice anything out of the ordinary from what I could see when replacing the head unit and besides this I have no other issues.

 

Automotive electronics are weird sometimes, it might just be a bad connection in the front panel.

 

Moving this thread to the appropriate sub-forum.

From what you described it does sound like a bad HU but to have the exact same issue with two separate units does seem odd.

I would check the ground for it which is behind the head unit.

​​​​​​@Wrathernaut can chime in, he has a lot more experience in this field than most of us.

 

Thank you sorry about that, didn't realize I wasn't in the right sub and double posted but couldn't figure out how to delete. I think I'm definitely gonna check the ground out. I checked out the error log in the system diagnostic in the secret menu, most notably "AV COMM CIRCUIT" can be caused by "AV control unit power supply and ground circuit malfunction"

The full error log list was:
CAN_COMM_CIRCUIT 12
AV COMM CIRCUIT 0
Internal Communication Error 9
Rear view Camera Connection Error 9
Camera Cont. Unit Connection Error 10

Note the camera errors are due to my car not having a backup cam, but the car which I pulled the unit out of did. Not sure if the other comm errors are due to the missing tech packages goodies like radar cruise

 

Missing CAN circuit is probably the culprit. I don't know exactly where the CANBUS plugs in but I believe it's a separate cable, probably not plugged in.

 

I pulled the head unit again, gonna check continuity and voltage but I can't seem to find the ground that you said is behind the unit. Would you be able to describe what I'm looking for? Thanks