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-   -   RESOLVED: Just replaced alternator & batt light still flickers. What next??? (

RenaissanceMan 02-17-2013 09:40 PM

RESOLVED: Just replaced alternator & batt light still flickers. What next???
Hey everyone-

For the last several weeks my battery light has flickered for about 2-5 seconds after starting the X5. The light always goes away after several seconds and the truck has run fine. It has always started right up without hesitation, and the battery never drained. The only other symptom was that my PDC would mysteriously turn itself on as soon as I cranked the engine (usually preceeded by a PDC light flicker for a couple of seconds). Unlocking the OBC revealed that I was holding a steady 13.9-14.1 volts while running. Did a lot of thread research here and got some helpful advice along the way... It was suggested that some component(s) inside the alternator was going South, so I decided to just replace the entire alternator.

Anyhoo, replaced the alternator today along with the belts & oil stand gasket, and when I went to start the truck, lo and behold I had the same exact symptoms as before: Flickering battery light for a few seconds immediately after cranking, and then it goes away. Still showing steady 13.9-14.1 volts. I'm assuming I didn't purchase an alternator with an identical malfunction, so now I'm thinking maybe the alternator was never bad in the first place.

Is there any possibility that my battery, even though it is holding charge and starting the truck w/o problem, could be doing something to cause this strange behavior??? I was going replace the battery next but wanted to ask the experts first. At a total loss here so any help is greatly appreciated! Thanks for reading!

upallnight 02-18-2013 05:34 AM

You can bring the battery to one of those auto stores that can load test the battery. Even a new battery can be defective as some new batteries are just re manufactured batteries from old batteries that are taken in.

QSilver7 02-18-2013 08:47 AM

Ditto...don't pitch that battery until you can find out if it truly is faulty. A load test would reveal if there is a dead cell etc. Also, check the battery to see if it has removable caps or lids so that you can check the electrolyte level. But as mentioned over on Xoutpost...I don't think the battery is the culprit, yet...the battery warning light illuminates when the alternator/charging system is the CULPRIT...and the battery is yet the VICTIM. :)

DTANDJT 02-18-2013 05:47 PM

It's the ignition switch . Had to replace mine. Battery light was flickering. Then the computer acted weird and my cruise control wouldn't work. It wasn't the alternator. After replacement, everything was fine. It was about $200.

RenaissanceMan 02-18-2013 07:06 PM


Originally Posted by DTANDJT (Post 7389562)
It's the ignition switch . Had to replace mine. Battery light was flickering. Then the computer acted weird and my cruise control wouldn't work. It wasn't the alternator. After replacement, everything was fine. It was about $200.

Wow, this may indeed be the most enlightening clue so far. I've been wondering if mine was the cause because I've had some other strange behaviors. Every once in a while, the starter will not engage on the first try. I have to turn the switch off and then on again before it will start. This happened intermittently last winter and then sent away when it got warm. I was still under CPO warranty when it was doing it last year but the dealer looked at it and said they couldn't do anything because it was an intermittent issue. The battery light never came on then, though... Ever since it started getting cold here this year, I've had the same issue creep up. Today I was actually experimenting with the switch and strangely enough when I turned the key to position 2 and let it sit there for a couple of seconds before starting, the battery light would not flicker. Safe to say something is screwy in there. I think you may be right. Is the ignition switch a relatively simple DIY? I'm a bit bummed that I replaced an alternator that wasn't bad but I'll be relieved once this is solved. Thanks for your post-

DTANDJT 02-19-2013 05:56 AM

Sounds like you're on the right track. I can't speak to DIY though.

DTANDJT 02-19-2013 06:01 AM

I also bet it causes intermittent cruise control issues I've read about. My X was doing that until the switch was replaced.

QSilver7 02-19-2013 08:21 AM

The ignition switch is #2 in the diagram below. There is a great DIY write up on on how to replace the ignition switch (the procedure will be basically the same on the e38 & e53 since they have the same design architecture...just do a page search [Ctrl+F] and type "ignition switch" as your search word to skip quickly to the DIY link):

A failing ignition switch can cause a lot of weird seemingly unrelated electrical gremlins...other than the fact that they all are actually related to the ignition switch in that the ignition has to be "on" in order for the electrical components to work. In the video can see some of the odd things you can sometimes get to happen by reaching over, pulling down the passenger sun visor, then opening the mirror cover (while the engine is running). If you can get the gremlins to appear....then you can pretty much bet that the issue is the ignition switch. If nothing happens...then it could or could not be the ignition switch. If the latter occurs...some have replaced the switch with success...and others have replaced the switch and the symptoms remain.

RenaissanceMan 03-04-2013 04:24 PM

Hey everyone, I wanted to post and let you know the problem has finally been resolved. I changed the ignition switch and everything is back to normal. No more flickering battery light, no more flickering PDC light, no more pulsing compass display, no more intermittent starting in cold weather, etc.

Of course, while I was still waiting on my new ignition switch to arrive in the mail, the X5 went into failsafe mode on the way home from work while I was doing 75 on the interstate and shut off completely. About 5-10 minutes before this happened the battery light started flickering and then went solid red. I knew something had suddenly gotten worse... The traffic was heavy (rush hour) and fortunately I had just enough momentum to weave through traffic to work my way over to the shoulder. I could not get it restarted to save my life. To add insult to injury, it was dark and raining cats & dogs. I had to finally relent and call the tow truck to get her towed home.

Moral of the story: If left undetected long enough, a failing ignition switch CAN leave you stranded.

The other moral of the story: Evidently what can appear to be symptoms of a failing alternator/battery can actually be the ignition switch in disguise. If you have a flickering battery light and your alternator appears to be charging properly and your battery is testing good, it could be the switch. In any case, I hope this thread will help somebody who might be chasing down a similar problem. Thanks everyone for your feedback and replies, They were a huge help in trying to figure all of this out!

QSilver7 03-04-2013 05:00 PM

Great...glad you found the cause & thanks for posting back it was resolved. :)

DTANDJT 03-04-2013 05:34 PM

Glad it worked out! Mine totally quit while driving too (before the switch was changed) and it totally stumped the AAA guy and the service techs. I hope I didn't pay for a spark sensor I didn't need before they changed the switch.

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