jmoffett

I was driving my 05 Auto last week to pick up my wife at work and touched the Scan "button" on the Nav touchscreen. I was playing music on an iPod connected to the XM mode through a PAL. Just as soon as I touched the screen, it went black but the music kept playing. Nothing on the head unit worked. I couldn't change the volume and the screen wouldn't open when I pushed the button. My wife's workplace is secure with a gate, so I needed to silence the music so I could speak to the security person through the call box. I shut off the ignition and opened the door. The music didn't silence immediately, but did a couple seconds later. After my wife got in the car, I pushed the start button and got a "No FOB Detected" message. I removed the FOB from my pocket and waved it around a bit and finally got a green light and started the car. The radio wouldn't work. I parked the car and didn't try to get in it until yesterday (Saturday...about 36 hours later). It wouldn't wake up and the door wouldn't open, so I replaced the FOB battery. That didn't work, so I got into the car manually so I could open the hood to find out my 1-month old battery was dead. I've never had any battery drain issues. When I replaced the battery and accessed the interior fuse panel, I could hear a humming sound from the dash area. I pulled the radio fuse and it stopped.

Notwithstanding the fact the radio doesn't work, that may have solved the issue. However, before I consider the case closed, I would like to know if anyone else has experienced this. Is there possibly an ulterior cause, or is it likely that the head unit is the sole source of the problem?

RoadkingC6

I see you say the battery was replaced a month ago, did you or someone else check the charging system to see if the alternator was putting out the 14 volts needed to charge the battery, sounds like a charging or battery problem to me.

EVRose

I had the EXACT same thing happen randomly with my 05 about 3-4 months ago. The first time my radio did that I didnt investigate for several hours and came out to a dead battery. I disconnected it and put a charger on it for an hour and got the car started and radio was normal. A few days later it happened again and disconnecting and reconnecting the battery got it back to normal. It happened 2 more times after that and I decided to put a charger on the battery for 6 or so hours. I havent had any more problems since then but my voltage is fluctuating all over the place especially with the AC on. I have a Billet Tech alternator on order. I'm hoping everthing will be good after that.

jmoffett

I put the fuse back in and the radio works again, but it's pulling about 3.5 amps with the ignition shut off. When I pull the fuse, the amp draw drops back down.

And I did checking the alternator. It's putting 14.4 volts back in at the battery.

Gearhead Jim

Wow!
Is it pulling that much after the door has been opened, and the Retained Accessory Power has shut off?