Radio won't turn on
 

Been having a couple of problems on the e53 with the radio. Was a few times where the radio would not shut off, even after turning off the car. It would eventually turn off, I don't remember exactly how long it took or what I did, if anything, to get it to turn off.
Now, I shut the car off, while the radio was on, then came back 5 minutes later, started the car, and no radio. Pushing the 'On" button does nothing. All nav, board monitor and other functions work as normally.
I have pulled all the fuses related to the radio, turned the ignition on with the fuses out, replaced the fuses, still nothing. Have also unhooked/rehooked the battery.

Any other ideas?

Try unplugging and reseating the main connector on the tuner module in the trunk.

Try unhooking the battery again but this time wait a few minutes. once you reconnect the battery cables, the security system will count down and ask for your code. Hopefully this resets the system.

NOTE: Make sure you have the 4 digit security code.

My radio did something similar sometime back (not turn on - didn't have the on problem when the car was off though). It might be a low/faulty battery that could cause the system to act up.

Good luck.

Sounds like effects of water damage, remove the radio unit's top lit and take a peek inside. Traces of the corrosive damaged done by water in live systems are easily visible.

Make sure you power down the nav drive correctly **before** you unhook the battery though or you wil brick the nav computer.

Or you could try poping fuses 7 and 41 wait 30seconds and then pop them back in this will reset the radio as well.

Good point. I forgot about the powering down.