[The Silver Slammer]

Today whilst driving home (52 miles, about an hour + w/traffic) the battery light came on about half way home. Wipers got slower and slower til I got home. Right before I got home lots of lights came on, engine light, trans malfunction, etc. all of which I attribute to low battery. I hooked up the battery tender and found 6 volts. Thank goodness I made it home. got the following codes. I'm thinking alternator. looks pretty easy to change. what's a reasonable cost for one? any experience doing this on a e90 n55? thanks guys.

[Welcome to NBA Jam]

Alternator isn't too bad to swap. Remans are fairly expensive, around $400-500. You could try swapping the voltage regulator for $65-70, but there's no guarantee that it'll solve it. A new alternator will come with a voltage regulator.

[The Silver Slammer]

I've had one issue after the other with this thing since o bought it. Really tired of fixing stuff on it. I can't even enjoy driving it, just fixing, upgrading, fixing again, etc. Tell me there's and end in sight?

[The Silver Slammer]

It has a weird faint buzzing sound coming out of the speakers, but not music or radio related, sounds like humming, buzzing, reacts to putting it in gear, opening doors, trunk, hood, headlights on/off. Sometimes it goes away, then comes back on. Wondering if this might be related. Car wasn't driven much the last 5 years, first thing I had to do with this was put a battery in it. Never had it coded for it either, if that makes a difference.

[AJL]

Originally Posted by The Silver Slammer

Today whilst driving home (52 miles, about an hour + w/traffic) the battery light came on about half way home. Wipers got slower and slower til I got home. Right before I got home lots of lights came on, engine light, trans malfunction, etc. all of which I attribute to low battery. I hooked up the battery tender and found 6 volts. Thank goodness I made it home. got the following codes. I'm thinking alternator. looks pretty easy to change. what's a reasonable cost for one? any experience doing this on a e90 n55? thanks guys.

I had almost identical codes and a similar issue, which I learned the hard way was not because of the alternator. In my case, it was due to a faulty aftermarket "Delphi" ignition coil causing some sort of interference with the DME ->Alternator BSD communication.

Honestly it could be the alternator, but I would recommend charging up the battery and starting the car again. See if the alternator still charges. If it does, then maybe it's worth checking into the ignition coil possibility. With a reman alternator sitting at just over $400 from FCP, it's probably worth the time to check.

I wasn't the first to have bad ignition coils cause a problem, otherwise I would have never figured it out.

[The Silver Slammer]

Originally Posted by AJL

I had almost identical codes and a similar issue, which I learned the hard way was not because of the alternator. In my case, it was due to a faulty aftermarket "Delphi" ignition coil causing some sort of interference with the DME ->Alternator BSD communication.

Honestly it could be the alternator, but I would recommend charging up the battery and starting the car again. See if the alternator still charges. If it does, then maybe it's worth checking into the ignition coil possibility. With a reman alternator sitting at just over $400 from FCP, it's probably worth the time to check.

I wasn't the first to have bad ignition coils cause a problem, otherwise I would have never figured it out.

I had just replaced the OEM coils and plugs from FCP a couple months back, I'd like to think I can rule that out. I had the battery light come on once before, then I shut the car off and a couple minutes later it fired right back up, no problems, that was before I had MHD so I couldn't check the codes.

[AJL]

Originally Posted by The Silver Slammer

I had just replaced the OEM coils and plugs from FCP a couple months back, I'd like to think I can rule that out. I had the battery light come on once before, then I shut the car off and a couple minutes later it fired right back up, no problems, that was before I had MHD so I couldn't check the codes.

Did you buy the genuine BMW coils or the cheaper Delphi ones? I bought 2 sets from FCP of the Delphis and had the same issues with both. I started having issues a couple months after replacing the factory coils.

[Pladi]

most likely not the alternator, they rarely fail, if you have MHD its coils causing over current or noise on the charging circuit. This has been confirmed by other threads.

[Pladi]

Originally Posted by AJL

Did you buy the genuine BMW coils or the cheaper Delphi ones? I bought 2 sets from FCP of the Delphis and had the same issues with both. I started having issues a couple months after replacing the factory coils.

FCP delphi are original and alot of people run them without any issues.

This issue is more apparent with a tune/MHD. I just dont think is fair to start blaming it on fcp delphi's. There is more to this issue.

[The Silver Slammer]

Originally Posted by Pladi

FCP delphi are original and alot of people run them without any issues.

This issue is more apparent with a tune/MHD.

I went to PPK factory flash and haven't gone back (several weeks) til after I replace the HPFP which will be here saturday. No JB4 either. As i said earlier, this car sat for a while, not a lot of use for many years, like 5k miles driven in 5 years from the original owner. Maybe sitting around not being driven has something to do with it.

[AJL]

Originally Posted by Pladi

FCP delphi are original and alot of people run them without any issues.

This issue is more apparent with a tune/MHD. I just dont think is fair to start blaming it on fcp delphi's. There is more to this issue.

I can only speak to what I experienced. I didn't say they aren't original, or knockoffs. You are correct that many people run them without issues, I'm just not one of them lol.

Almost makes me wonder if there is some underlying cause that makes some cars more susceptible to the electrical noise.

[Pladi]

Originally Posted by AJL

Almost makes me wonder if there is some underlying cause that makes some cars more susceptible to the electrical noise.

That can very well be the case. Like not ideal grounding. Good enough not to cause major problems but not good enough when you are putting more demand on parts because of a tune.

[GoRomeo]

Originally Posted by The Silver Slammer

Today whilst driving home (52 miles, about an hour + w/traffic) the battery light came on about half way home. Wipers got slower and slower til I got home. Right before I got home lots of lights came on, engine light, trans malfunction, etc. all of which I attribute to low battery. I hooked up the battery tender and found 6 volts. Thank goodness I made it home. got the following codes. I'm thinking alternator. looks pretty easy to change. what's a reasonable cost for one? any experience doing this on a e90 n55? thanks guys.

Most likely a bad battery. Do a load test before anything.

[The Silver Slammer]

Originally Posted by GoRomeo

Most likely a bad battery. Do a load test before anything.

Will do, but it is a new battery, replaced it in September.

[GoRomeo]

Originally Posted by The Silver Slammer

Will do, but it is a new battery, replaced it in September.

Ok, well do it anyways and have them test your alternator while doing this... The same machine used to do load test can also test your alternator. If that's OK, look for your ground straps around the car and check them for corrosion and stuff.

[AJL]

Originally Posted by Pladi

That can very well be the case. Like not ideal grounding. Good enough not to cause major problems but not good enough when you are putting more demand on parts because of a tune.

Yeah, I thought of grounds. Checked the big 'ol honkin engine to frame ground strap under the car, and also the common ground point on the left side of the engine bay. Both were perfect. As was every ground on the VCG area.

Who knows... I'm sure someone will figure it out eventually.

[The Silver Slammer]

Had the battery and the alternator checked out tonight at the auto parts store. Both checked out ok. Battery was exceptional like I expected being brand new and he said alternator was working producing 14.6v. Don't really know what more to say about that. I'll check all the grounding points this weekend. Meanwhile if I am successful at posting this log will someone with some real experience look at it? Retuned the car with MHD stage 2+ to see if that would affect anything and snapped a few logs.[IMG]undefined[/IMG]

[The Silver Slammer]

The battery that was changed back in September was never registered or coded. It's likely that has lead to some of the issues I had. I coded it and registered it last Thursday and since have driven quite a bit and have had no issues so far. I'll keep my fingers crossed.

[The Silver Slammer]

Coded the battery using INPA and so far no issues.

[SnailBums]

Originally Posted by The Silver Slammer

The battery that was changed back in September was never registered or coded. It's likely that has lead to some of the issues I had. I coded it and registered it last Thursday and since have driven quite a bit and have had no issues so far. I'll keep my fingers crossed.

Not registering the battery will cause plenty of weird electrical issues. The vehicle still thinks that the old battery is installed so the alternator is overcharging or undercharging.

You also have some BSD faults that may be related to the issue. Make sure you clear all those faults since you already registered the battery.

Mike

[The Silver Slammer]

Originally Posted by SnailBums

Not registering the battery will cause plenty of weird electrical issues. The vehicle still thinks that the old battery is installed so the alternator is overcharging or undercharging.

You also have some BSD faults that may be related to the issue. Make sure you clear all those faults since you already registered the battery.

Mike

Yup all done and working like a charm now. Thanks!

[hot sauce dude]

Originally Posted by AJL

I had almost identical codes and a similar issue, which I learned the hard way was not because of the alternator. In my case, it was due to a faulty aftermarket "Delphi" ignition coil causing some sort of interference with the DME ->Alternator BSD communication.

Honestly it could be the alternator, but I would recommend charging up the battery and starting the car again. See if the alternator still charges. If it does, then maybe it's worth checking into the ignition coil possibility. With a reman alternator sitting at just over $400 from FCP, it's probably worth the time to check.

I wasn't the first to have bad ignition coils cause a problem, otherwise I would have never figured it out.

This was the only search result that I had immediately found regarding the idea of coils interfering with alternator charging. Very recently, in one go I had replaced all 6 coils with Eldor, couple hood struts, cheaper crank seal guard, and inspected the voltage regulator which looked great so I did not at first install the new one I just purchased.

But then the alternator didn't charge, even with the new VR. So confused. Longer story short, I pulled out the alternator and had it tested at a rebuild shop. Passed with flying colors. Wtheck. After finding this post, I decided to swap back out the old 6 coils. Then I got charging. Crazy, huh?

I wanted to see if my issue followed the coils, so I put the new ones in one more time. I still have charging, nice. I don't know how, but I'm not complaining! So if someone sees this post several yrs from now bc you're in a similar situation, I say give it a shot.