e39 M5 CD changer not recognized - possible culprit?

[alendsm]

When using the MODE key to switch between Tape/Radio/CD most of the time it will just switch between tape and radio as if the CD player doesn't exist. Sometimes, however, it does change to CD and I have no issue playing it until I shut off the car. Often times, even if I turn the car right back on it won't change to CD. It seems to be pretty random - unless temperature is a possible culprit? Its been very hot lately.

Thanks!

[alendsm]

Any ideas? Its cooled down lately and still here. Yesterday, I fiddled with the CDs (took some out, changed em around) and the first time I tried it still no luck. Then, about 20 mins later when I started it up again it worked. Like I said, very random (it seems.)

[bmwdirtracer]

Is there any sign of water in the trunk? Look down with a good flashlight in the corner, under the CD changer (behind the panels) I'd probably unplug all plugs on the changer, clean both sides of each plug with Electronics cleaner, and replace the CD changer's fuse, for good measure. Make sure the trunk is perfectly dry.

If problem recurs after that, I'd hook the car up to a GT1 computer, and see whether any of the tests available might help you. What year is this car? Any water leaks anywhere, into the car interior or trunk?

[atakordie]

Bumping this thread because I have the same symptoms as thread starter, and after searching for a few days, I can't find any answers. There are no signs of water ingress or damage in the left rear trunk area either. Battery is at 12.6 V with car off and charges at 13.6 V with motor running. CD changer itself plays flawlessly when it is available as one of the modes. I do not have any aftermarket mp3 players connected. Ignition switch (OE supplier as I recall...not dealer sourced) was changed at about 120k miles; car is at 150k miles now. No issues with factory audio albums or CD-Rs with mp3s when working. All fuses look fine. I have scanned the changer, radio, DSP amp, and MKIV nav computer via INPA...no errors are shown. I am not sure how to test the ibus, but cruise control works regardless of no CD changer operation, and I haven't had any issues with lighting/LCM that I know of. Anyone have a suggestion for a plan of attack for me to fix this irritating issue?

[bmwdirtracer]

Even without obvious water ingress. I suggest unplugging and cleaning both sides of all plugs into the cd changer. With ignition off, just spray both sides of the plugs thoroughly with electrical contact cleaner, and brush with a toothbrush, then spray again, and blow or shake the plugs to get rid of excess cleaner (it dries very fast anyway). You also might want to check whether the CD player itself has an integral fuse - it will be obvious if you examine the back of the unit, wherever the plugs go in. Clean the fuse hole, swap fuses for good measure, or at least test and examine it (test is for continuity- should be perfect.)

[atakordie]

Even without obvious water ingress. I suggest unplugging and cleaning both sides of all plugs into the cd changer. With ignition off, just spray both sides of the plugs thoroughly with electrical contact cleaner, and brush with a toothbrush, then spray again, and blow or shake the plugs to get rid of excess cleaner (it dries very fast anyway). You also might want to check whether the CD player itself has an integral fuse - it will be obvious if you examine the back of the unit, wherever the plugs go in. Clean the fuse hole, swap fuses for good measure, or at least test and examine it (test is for continuity- should be perfect.)

Used DeoxIT D5 contact cleaner on the power and coax cables & connections. Problem persists. I didn't see any fuses after taking the rear cover off of the changer. Tested the power connections from the harness @ 12.61 V positive to negative and from i-bus to ground @11.54 V. I am not sure where the other end of the power harness/ibus connects...it seems to lead toward the cabin underneath the trunk trim panels.

[speed7]

So this issue just happened to me today. I am actually using the dice bluetooth unit that is plugged into the cd changer location. Just as of now it's MIA.. as if it isn't even connected. Navigation is still there and you can see activity on the DVD player.

What's the consensus? 2003 540iT.. 144k miles... just gremlins in the system? Better to change out the head unit with a double din dealio that has bluetooth built into it? That's the route I most likely will be taking.

In that area.. no water.. car is parked in a garage and for the most part is well maintained. Love the car but enough of these little things popping up and might have to let it go for something a bit newer and with less miles. =(

[Tibbys96Z]

I have the same problem just like others described. Seems totally random although it only works 1/10 times I drive.