My charging indicator is lit. A voltage check at the battery with the car running shows less than 12 volts. I've fully charge the battery and checked all the connections and fuse (#15). If the alternator would a double digit price (and easy to swap), I'd replace it as part of the troubleshooting. But, a $500+ cost plus the pain of draining the coolant makes me question whether there might be another cause. Any recommended tests that can be performed with a voltmeter? Are there other fuses or relays involved in the charging system? Other... Thanks for your help.
Yes. Any ideas? Without other previous suggestions, I purchased a rebuilt alternator. Choices ... dealer $998, Pelican $438, CSK (Autolite) $560. The Autolite had a lifetime warranty the Pelican was a Bosch rebuild with a 2 year warranty. In the end I went with the Bosch. Yesterday it arrived but the housing for the wire connection was cracked. Pelican responded well and is picking it up and sending out another. Fingers crossed that an alternator solves the charging problem. Has anyone ever disassembled one of these sealed alternators?
I had a similar issue. I went to drive one morning and the seatbelt and airbag light would not go off. Later the Charging light came on and "TRANS FAILSAFE PROG" displayed. I looked on line and found it could be the charging system. After much grief over the cost, I decided to have someone check the charging system. Well, it was determined that a faulty Brake Light Switch was the culprit. Apparently, it sent faulty signals and varied in voltage. This caused the computer to think I had no brakes and threw Limp codes. I replaced it for $40, plus the $80 to have the diagnosis, and all warnings and codes vanished. In fact, it passed inspection with flying colors the next day. Have your charging system checked. I would have replaced the alternator and still had the problem. Hope this helps.
Must be the month for charging problems... My charging indicator came on today as well, or rather never went off after starting. Turning off all electrical accessories and keeping a conservative eye on things, I made it home without incident. After checking the battery connections and hooking a volt meter up to things, I'm getting no sign of alternator output. (voltage does not rise with engine running and only continues to drop down into the 10-11V range) I didn't see any blown fuses, but will check for #15 again. Does anyone know the pinout on the alternator connector or a way to confirm the alternator is indeed the problem? On some forum I found mention of one of the pins essentially going to the charge fault light, while I expect the other pin should go to an ignition on (e.g. KL50). Should I see battery voltage on one/both of the alternator connector pins when disconnected with the engine running? That being said, most people just say to check the voltage with the engine running, but I just want to make sure there's not an issue with something else, like a bad connection to the alternator in the first place. Sadly, one person even recommended disconnecting the battery with the engine running -- eik! Barring any other options, If I can't get the car in tomorrow, I'll be DIYing a new alternator on this one. It's an 02/540i6 with nearly 100k miles, so it's probably about time.
Yup. Was the alternator. Cheapest I could find locally that I could get same day was $690+core for a rebuilt Bosch. Same as OEM, minus the roundel. Good news is that the replacement went without a hitch, though my attempts to do it without removing the fan shroud were thwarted when I was unable to gently extract the old unit. Charging fault light is out and battery voltage is good. I also now keep the cheat sheet for the cluster tests in the car. One of the tests provides a continuous readout of battery voltage. Quite handy when I had to drive almost 20 miles to get to a place where I could work on the car. On a side note, does anyone know how to read the date codes on the OEM batteries?
I thought I was reading my events in devurandom's post. Same year car, same symptoms only mine has a mere 60K miles. Today, I installed a Bosch "rebuild" and all is well. Everything about this rebuild looked new (pulley, castings, plastic). I was impressed and compared with devurandom's source, Pelican strikes a very good deal. I did need to wait over a week and one return to get the same alternator.
