Another Newbie with Weird Electrical Problems

[saw005]

Hi Guys

Long time lurker, first time poster here.

I have a '04 4.4i with 44,000kms nav but no DSP and just lately it is having strange electrical issues.

I had the lights lit up like a Christmas tree/Engine trans failsafe issue which turned out to be a bad alternator which was replaced under warranty (thankfully) however it did leave us stranded in the middle of no where for 5 hours while BMW Roadside assist came to get us. A long story for another time. Anyway the battery was replaced at the same time.

Since then, and this is the problem, I have had the radio cut out sound then come back on. First time this happened DSC light came on then off. Stealer said was an overcharging issue and gave no further explanation. It has happened again this week however, no DSC light, just the radio but now the radio looks like it is trying to restart, so it cycles through the BMW symbol when you first open the drivers door then goes to radio (all whilst driving along). Last night as I was pulling into my drive, the engine just cut out, all lights on like when you go to start the car. Turned the key off and restarted. No warning lights or anything, just as normal.

Does this sound like an alternator or battery issue or am I now looking at something else?

I had a similar problem with my last car, MINI Cooper S where the stealer had to replace the transmission (loose bolt head floating in it) and they didn't reconnect the alternator properly. Engine would just shut off. Turned out to be a loose connection wire that was shorting.

Going to the stealer when I can get it in but any ideas would be appreciated. (sorry for the long post)

Cheers

[killcrap]

sounds like an ignition switch failure.

[Weasel]

If it is overcharging it can cause electrical gremlins just as well as undercharging can... and they should have replaced the alternator under parts warranty for a voltage regulator issue. As far as the stalling when pulling it the driveway, it may be something like a cam sensor getting flaky... but there would be a fault stored in that case.

Just give the dealer all the details you can and they should be able to fix you up.

[saw005]

Thanks for the quick replies guys. It's booked into the stealer next week so we'll see if they can find out what's wrong.

[KoPe]

Hello, any solution to problem? I am having similar issues with e90 -05 with DSC, radio cut off and sometimes power going off for a millisecond. E90 technichs are partly similar to X5. Alternator is overcharging and undercharging. I changed the voltage regulator and the problem seem to be solved for a while, charging was stabilized, but now it begun again. I have doughts that the alternator broke regulator again but seems like You are having similar problems after replacement of alternator?

[saw005]

Sorry to hear that you are having similar problems. I took the X to the stealer. As well as looking at the electrical issue, I asked them to look at the idle speed, as the car was only idling just a fraction above 500 rpm. Anyway whilst looking at the idle speed they found that the pc (???) valve (breather valve?) was cracked and so replaced it under warranty and advised that is why the engine would be running rough. To tell you the truth I didn't really notice that. To cut a long story short, they couldn't find anything out about the electrical issue unless I wanted them to basically rewire the car.

They did put the car onto the diagnostic machine and run a series of tests. The results all showed ok (they showed me the printout). This time there were no error codes stored in the computer so there was nothing to go on.

However since going in, the car is running appreciably better, idling more evenly and throttle response seems better. There has been no showing of the earlier electrical problem. It makes me think that they did find something but wont admit it, but I am pretty friendly with my service advisor (had the same one for about 6 years now) so I would think that they would tell me if there was something wrong.