So about a month ago, i started my car to be greeted by the lovely "increased battery discharge" warning, proceeded to let the car sit for a while and warm up. When i turned it off and the started it again, warning went away. Didn't really think anything of it. About a week later, it did it again, and then multiple other warnings came up (ABS, DSC, and many others) and then it killed itself at a stoplight. I hadn't replaced the battery since i purchased the car a little over a year ago, so i went ahead and did that and coded it through Carly. Everything has been running fairly good, except for the fact that when i monitor the voltage on the in dash tool, it will start off reading 11.8v and then once ive driven it a considerable amount, it will jump back up to around 13.5-14.5 V. I know that 13.5-14.5 is a very reasonable number, but should it take almost 30 minutes of driving to get to that point? Im also due for the positive battery cable recall, and am doing so next week. Just seeing if anyone else has had the same issue. If i let the car sit for even just a day, ill have weird issues like the headlights not coming on when i unlock the car and some instrument panels will clear themselves when i start the car. I feel like its alternator related, but then how could it eventually go back to normal voltage? Faulty Battery? I did pull codes and the 00278D "generator communication" code came up. Voltage regulator issue? IBS issue? Let me know your thoughts.
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01-25-2020LAST POST
Did the battery cable recall fix the issue?
shklog wroteIt's most likely your alternator. Voltage should jump to ~14V within 10 sec after star up. This happened to me and several others here. My alternator had a cracked bearing housing so the whole thing was toast. At first it would take a while to kick in and increase voltage. Then it got to the point where it would only kick in after a restart. Then that stopped working and the alternator never generated a field. I replaced mine myself and would suggest replacing the alternator (plus regulator) rather than trying to replace just the regulator itself.So about a month ago, i started my car to be greeted by the lovely "increased battery discharge" warning, proceeded to let the car sit for a while and warm up. When i turned it off and the started it again, warning went away. Didn't really think anything of it. About a week later, it did it again, and then multiple other warnings came up (ABS, DSC, and many others) and then it killed itself at a stoplight. I hadn't replaced the battery since i purchased the car a little over a year ago, so i went ahead and did that and coded it through Carly. Everything has been running fairly good, except for the fact that when i monitor the voltage on the in dash tool, it will start off reading 11.8v and then once ive driven it a considerable amount, it will jump back up to around 13.5-14.5 V. I know that 13.5-14.5 is a very reasonable number, but should it take almost 30 minutes of driving to get to that point? Im also due for the positive battery cable recall, and am doing so next week. Just seeing if anyone else has had the same issue. If i let the car sit for even just a day, ill have weird issues like the headlights not coming on when i unlock the car and some instrument panels will clear themselves when i start the car. I feel like its alternator related, but then how could it eventually go back to normal voltage? Faulty Battery? I did pull codes and the 00278D "generator communication" code came up. Voltage regulator issue? IBS issue? Let me know your thoughts.
It helps if you search, a quick search of that error code turns up this very in depth thread another member created and what he did to solve the issue.
https://www.m3post.com/forums/showthread.php?t=1470613
https://www.m3post.com/forums/showthread.php?t=1470613
shklog wroteI posted this another thread a moment ago, but that person already replaced theres.So about a month ago, i started my car to be greeted by the lovely "increased battery discharge" warning, proceeded to let the car sit for a while and warm up. When i turned it off and the started it again, warning went away. Didn't really think anything of it. About a week later, it did it again, and then multiple other warnings came up (ABS, DSC, and many others) and then it killed itself at a stoplight. I hadn't replaced the battery since i purchased the car a little over a year ago, so i went ahead and did that and coded it through Carly. Everything has been running fairly good, except for the fact that when i monitor the voltage on the in dash tool, it will start off reading 11.8v and then once ive driven it a considerable amount, it will jump back up to around 13.5-14.5 V. I know that 13.5-14.5 is a very reasonable number, but should it take almost 30 minutes of driving to get to that point? Im also due for the positive battery cable recall, and am doing so next week. Just seeing if anyone else has had the same issue. If i let the car sit for even just a day, ill have weird issues like the headlights not coming on when i unlock the car and some instrument panels will clear themselves when i start the car. I feel like its alternator related, but then how could it eventually go back to normal voltage? Faulty Battery? I did pull codes and the 00278D "generator communication" code came up. Voltage regulator issue? IBS issue? Let me know your thoughts.
"I have an an alternator off of a 2008 e92 m3. Everything works on it when I took it off. Has about 100k miles on it. I would part with it for super cheap bc its just sitting in my garage now. I swapped mine out along with pulleys, valve cover seals etc... pm me if interested."
Redd wroteBattery registration is an important thing haha. I actually have ISTA as well. I use it sometimes, most of the time I just use Carly.
Redd wrotethats crazy....i would never think that that is considered "normal", but if it is, i guess ill just deal with it lol. Ive been monitoring it a lot after i got the battery cable recall done just to eliminate more factors and did notice a couple of interesting things. When i cold start it, it will of course be sitting at 11.8~11.6V depending and continue to be that way. If i stop and start the car again after driving it for a little bit, it will jump right up to 14v immediately when i start the car. Weather also is making it act very funny (as expected when it hits 20 degrees F out). I parked it in a parking deck at work for about 8 hours on a very cold day and came back out to the lovely "increased battery discharge" warning....but it never killed itself while running so im not terribly worried about it.
shklog wroteIts very likely your alternator is on its way out. It tends to happen slowly. If it discharging while off that can be the voltage regulator. If its not charging at adequate voltage its likely the alternator. If you are doing the voltage regulator, Id just change the alternator. It takes some decent time to get im there and pull the alternator out. At that point you can just swap it. I have an extra one its your if you want for like $50-$60. Its off an 08 though.Redd wrotethats crazy....i would never think that that is considered "normal", but if it is, i guess ill just deal with it lol. Ive been monitoring it a lot after i got the battery cable recall done just to eliminate more factors and did notice a couple of interesting things. When i cold start it, it will of course be sitting at 11.8~11.6V depending and continue to be that way. If i stop and start the car again after driving it for a little bit, it will jump right up to 14v immediately when i start the car. Weather also is making it act very funny (as expected when it hits 20 degrees F out). I parked it in a parking deck at work for about 8 hours on a very cold day and came back out to the lovely "increased battery discharge" warning....but it never killed itself while running so im not terribly worried about it.
Alternatively, I suggest just buying a new valeo 180amp alternator or you can check the autoparts stores for remanufactured ones. Those will be cheaper. Maybe a bit less than $200. The valeo will be $280ish from fcpeuro or ecstuning.
Im not sure if its your alternator, but its a possibility. You'll just have to run scan codes. Consulting an indy shop might not be a bad idea.
Also if you do it yourself, I suggest getting a belt wrench instead if using a box end wrench. You'll get more torque that way and it'll be much easier haha. After going super charged, I have found that to be a great tool.
shklog wroteI know the feeling. I was going nuts monitoring the voltage every few mins. I've been left stranded by the road side by a dead alternator before so I had good reason to be paranoid.thats crazy....i would never think that that is considered "normal", but if it is, i guess ill just deal with it lol. Ive been monitoring it a lot after i got the battery cable recall done just to eliminate more factors and did notice a couple of interesting things. When i cold start it, it will of course be sitting at 11.8~11.6V depending and continue to be that way. If i stop and start the car again after driving it for a little bit, it will jump right up to 14v immediately when i start the car. Weather also is making it act very funny (as expected when it hits 20 degrees F out). I parked it in a parking deck at work for about 8 hours on a very cold day and came back out to the lovely "increased battery discharge" warning....but it never killed itself while running so im not terribly worried about it.
The good news is, after my last posting in that thread, my car has not given me any more issues. No errors, no increased batt discharge messages, voltage all normal. As far as my case is concerned, it appears that it is normal for the alt to undercharge the batt after registration.
Regarding the 1st post 00278D it’s the alternator
I had the same code ever since I bought my 2010 went away after replacing a refurbished unit from fcpeuro
Drove like that for 2 years, car died twice, changed battery twice
Also had the IBS and glove compartment recall for the wire done
Haven’t had the code since
I had the same code ever since I bought my 2010 went away after replacing a refurbished unit from fcpeuro
Drove like that for 2 years, car died twice, changed battery twice
Also had the IBS and glove compartment recall for the wire done
Haven’t had the code since
