Hello all. First time poster & long time reader here. I have a 2011 G37 Sedan RWD AT 185000 miles no mods. I was having issues with intermittent radio function. I purchased a used O.E. radio and installed it. During the install I switched the connector for the AV unit with the Unified Meter/ AC Amp connector (yellow taped one). I proceeded to reconnected battery power. I turned the car on and the gauge cluster (combination meter) and backup camera are not functioning. Radio and HVAC functioning as they should. My question is that by misconnecting these connectors, would that damage the Unified Meter/ AC Amp? Research has told me the Unified Meter/ AC Amp controls the gauge cluster but I'm not sure about the backup camera. Thanks in advance.​​​

 

It was so mean of them to make those two close plugs (accidentally) interchangeable.

I don't know if the error would actually damage the AC amp but hopefully you've only popped a fuse in the process. The ones to check are 3, 4 and 19 in the in-cabin fuse box (near the driver's left leg) and then possibly 34 and 45 in the IPDM (inconveniently mounted on the firewall behind the battery).

Last question - is your AV system a "Base Plus Backup Camera" or Bose? And with or without NAV? I presume the replacement radio you got was the same part number?

 

After the incident I checked every fuse, all had continuity. AV system is base w/ backup camera no nav. I have ordered a AC Amp from ebay. Waiting for it to arrive so I can CAREFULLY install it to see if that's the problem. I didn't realize until recently how may things are tied to the AC Amp. I also swapped the relays behind the radio to the right (M69 for the backup lamps/ reverse signal, and M70 for the heated seats). Heated seat still works, camera does not. I failed to mention the reverse lights are also out. This is why I thought it may be the relay. Once the new AC Amp is installed I reply back with an update. Thank you for your assistance. If you or anyone else has any other suggestions I'm all ears.

 

Hope that replacement AC Amp brings it all back to life. However, you may need to do a bit more digging. Because if your back-up lights and relay are not working, then pin 94 of the AV unit is probably not getting the 12V it needs to trigger the backup camera to be displayed. The diagram you posted from the External Lighting FSM is confusing because your AV FSM shows the Fuse #4 circuit below. But the AV unit definitely needs to know when to activate the camera and the signal comes from that reverse switch / backup-light circuit.