XSeries-forum

i have a friend with a 03 3.0i X5 and after doing all the battery tests and alternator tests ,the alternator is working but not charging the battery. once the car is started up the alternator feeds the engine but not recharging the battery. after this issue the PDC doesn't seem to work either. any ideas??thanks in advance

I believe there is a module that controls the feed to the battery from the alternator. This may be the culprit. Although it could be the alternator itself. My 4.8 went back and forth to the dealer I don't know how many times to try and sort a charging issue and in the end they replaced my alternator even though they still couldn't fault it. Been fine ever since. The E53 is riddled with electrical gremlins unfortunately.

I've lost track of how many alternator issues I've had in the last few years where the AA has come out and tested the alternator and it still tests fine but is knackered! Alternator should be putting out 13.5V to 14V if it's charging, so with a MM on your battery you should see this voltage at least (engine running, engine off a good battery should have 12.4V min. Less than that and it's not fully charged).

My 911 alternator was goosed, the car would run fine for days until I topped up with a charge (CTEK 7000 it sufficiently discharged one day where all my engine lights came on one after the other, the ABS, traction, airbags, heaters and AC, then the windows, then the alarm! I was still driving and attempting to get to my mothers I made 3 miles without any juice at all and with the alarm going off. Anyhoo, alternator was the culprit and it was the electronic gubbings................. £900 for a new alternator, £400 for fitting!!!! I wished it was a Ford Escort and I could get one from the scrappy for £5 and fit it in 5 mins myself with a Halfrauds bike spanner!

my friend is going to drop off the vehicle with me to look at so i'll test the battery and alternator one more time and start looking for the module if there is one that controls that recharging. thanks for quick replies

got it all sorted.. it was the alternator regulator which was making the alternator look like it is working when we test and not working to charge the battery when it needs charged.after 140 quid it is working now.and the back up sensors came alive after this fix as well. so did the automatic wiper option

Excellent! Good news