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COMAND nav DVD heat problem

6K views 17 replies 5 participants last post by  jaymaynard 
#1 ·
I think my COMAND unit has a heat problem. After driving for 30 minutes or so, the navigation quits working and comlpains about not being able to read the DVD. The disc itself is good; the thing works after it's sat for a while and cooled off. I think the DVD drive is overheating.

Is this a common problem? Am I going to have to replace the entire head unit? If so, how big a job is this? I'd like to have it working before I set off on a trip Saturday...
 
#3 · (Edited)
My search-fu wasn't up to turning up that thread. Guess I'll have to pull the unit and see if that fan is running. Now to find some instructions...

Edit: Damn, that looks easy. I'll have to take a look tomorrow to see what I can see.
 
#6 ·
I got it pulled out and looked at it a bit. Both fans spin freely. I wasn't able to get the top cover off the unit to see if the nav fan was actually plugged in; some idiot had already stripped the screw head. Still, nothing leapt out at me.

The good news is that getting the radio in and out is a piece of cake, so I can poke more later.
 
#7 ·
As in my post that was linked, I had same problem. First of all, where did you get your nav dvd?
If it is original, then the nav dvd will get worse and eventually quit. There's a guy on ebay, Jimmy Chen who is the cheapest repair I could find. He's in NJ and for $250 he will fix anything wrong. He's an Alpine expert. Sent mine in and had it back within 7 days with a new nav dvd and 6 months warranty. He gave me his cell # if I had any problems. Only problem is that he is hard to understand but you can get what he is saying.
 
#8 · (Edited)
My nav DVD is a 2012 original. I've thought about imaging it, then burning another copy and trying that, just to see. The only problem with this theory is that I wouldn't think the DVD itself would be unreadable with heat...

$250 for a fix and a current nav DVD is a hell of a deal, considering that a new nav DVD all by itself is $250. I'll have to hunt him up, though it'll be after the holidays.

Edit: Well, crap. So much for that idea. The nav DVD must be dual-layer; it's 7.01 GB. I can't burn dual-layer DVDs.

Edit 2: Surprise, surprise...my Mac Pro can write DVD-R DL and DVD+R DL. Wonder which would work better...
 
#9 ·
He put a new DVD reader in it. I didn't get a new Nav disk. The original Nav disks have certain files in them that won't copy for counterfeit protection. Sometimes they will work for awhile but then quit. Many of the ones on Ebay are copies and they work for a few months then crap out. All these sellers have good reviews so they work long enough to get a good review. Don't ask me how I know!
 
#12 ·
This also happens to me after a long drive (8 or more hours). I eject the dvd media and notice that the disk gets dirty with some kind of soot. I just wipe it with a cloth and it works fine after that. Nowadays, on long journeys I make sure i turn the Nav/Radio off every now and then.
 
#13 ·
I sent it off to Jimmy Chen in NJ last Monday, and got it back today. Prompt service, and seems like an easy guy to deal with.

The unit appears to work correctly. He put a new DVD drive on it and checked it out, and even burned me a backup of the disk.

Only one problem: the compass is off. The moving map shows the vehicle pointed in all sorts of funny directions, even as the map position updates correctly, and the instrument cluster compass display shows the same heading as the compass on the map display.

Is there a way to force a recalibration of the compass? The vehicle FM says that the calibration function is disabled if there's a navigation module installed, and the COMAND manual is silent on the subject.
 
#15 ·
Well, it's not calibrating itself. Watching it, it seems that the yaw sensor is acting like it's backwards: when I turn right, the map display acts like I've turned left. This will most likely get in the way of it calibrating itself.

Is there any service documentation anywhere on how to set this up, or configure it, or calibrate it, or...? This is really going to annoy me.
 
#16 ·
Final resolution: I sent it back to Jimmy Chen to fix. He found the GPS antenna connector on the replaced nav unit to be broken. He swapped the nav unit again, and now it's working correctly.
 
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