2E97 Alterntor Issue

lowrydr310 · 01-18-2019, 09:48 PM

When I started my car this morning I got a red battery warning on the center display along with a "Charging system malfunction" message on my iDrive display. I was about to move my kids to my wife's car but the warning went away after a moment so I kept them in the car and drove them to school. I drove 10 minutes without issue, shut the car off to walk my kids into school, restarted the car and drove home. As soon as I pulled in my driveway the red battery icon appeared again along with the same charging malfunction indicator.

I immediately hooked up my laptop and there's a 2E97 code set in DME/DDE, indicating an alternator problem. I looked at the freeze frame data in INPA and it indicates only 11.88V were measured.

I haven't begun much diagnostic work yet because I've been busy today, but I wanted to check and see if there's anything specific I should be looking at. Is it just as simple as a bad/failed alternator? As far as I can tell it's the original alternator with 225K miles on it, and if true I wouldn't be surprised that it failed. I can't find any service records from the past ownership (have some but not all records) indicating any alternator replacement and I can see a BMW logo on the side of the alternator.

Coincidentally it's been raining pretty heavily all week (and I haven't replaced my under tray yet!). Another coincidence is just last night I hit a nasty pothole that opened up because of all this rain. I'm not sure if that's related but it's odd that I got the alternator error right after these events.

I checked the battery tray and there are no puddles or any other signs of water. The battery terminals are perfectly clean with no corrosion. Visually the alternator looks fine, the power wire is still attached solidly and has no corrosion. Where's the engine ground cable located? I want to check that next. I'm going to measure voltage while running with a multimeter, and then tomorrow I am planning to remove the alternator and battery and get them tested at my local auto parts store.

Welcome to NBA Jam · 01-18-2019, 11:12 PM

The voltage regulator is usually a good start since it's cheap(er) than a full rebuilt alternator. Alternators themselves are fairly robust, but they can fail.

gbalthrop · 01-19-2019, 01:07 AM

Quote:

Originally Posted by lowrydr310

When I started my car this morning I got a red battery warning on the center display along with a "Charging system malfunction" message on my iDrive display...I immediately hooked up my laptop and there's a 2E97 code set in DME/DDE, indicating an alternator problem. I looked at the freeze frame data in INPA and it indicates only 11.88V were measured.

What Scan Tool or Software did you use to read the "2E97" code? There are 4 different P-codes associated with that BMW FC, so if your scan tool/ software did NOT provide a definition, it's not helping other than you have an undefined issue with the alternator. INPA provides a definition (albeit in German, but Google-translatable ;-), and it also displays the corresponding P-code which is helpful in such situations. Here are the 4 possible codes with Definitions per Bentley:
POA3B | 2E97 | Generator Over Temperature
P0620 | 2E97 | Generator Control Circuit
P3223 | 2E97 | Generator Mechanical
P324A | 2E97 | Generator Type Implausible

I would start by checking to see that the BSD bus control wire is firmly attached to the Alternator at the rear Voltage Regulator cover. If your scan tool can read Parameters (Live Data) and you can read actual system voltage with the engine running, you can see if you get a reading in the range of 13.5V to 14.8V with motor running, or you can use Hidden Menu 9.00 to do that per this procedure:
http://e90.wikifoundry.com/page/BC+hidden+menus

George

Efthreeoh · 01-19-2019, 06:11 AM

I'm pretty sure 2E97 is the code I got when my alternator died at 314,000 miles; I'll have to check my book in the car to be sure. My car came up with the red battery light on my way to work. I stopped and scanned the ECU with my Schawben BMW scan tool, which I keep in the car. I restarted and the trouble light was not lit, so I thought it was just a battery issue. The light came back on in about a mile. I repeated that event one more time. The light came back on, I was about 25 miles from home. It was December, cold and raining (heat, lights and wipers). I made it back home and the engine died in the driveway. It wouldn't restart because the trip home consumed the energy in the battery.

Not being fancy, about it, I figured the alternator at 314,000 miles went tits up, so I replaced it with a BMW OE unit. Not a wink of trouble since then. The battery went about anther year until it wouldn't hold a charge ample enough to start the engine after just a few days sitting. It was over 7 years old at that point.

I too debated whether to check the voltage regulator, etc., but since it takes enough time pull the alternator, I just took a WTF attitude and decided not chasing the voltage regulator was a better use of my time.

My 2 cents.

Boland01 · 01-19-2019, 08:15 AM

Our335i did the same thing and was only charging a little over 10 volts. Since you have to take half of the engine off (or it sure seemed like it)I went ahead and just replaced the whole alternator too. 6 months later no issues.

PhaseP · 01-19-2019, 12:21 PM

Quote:

Originally Posted by lowrydr310

As far as I can tell it's the original alternator with 225K miles on it, and if true I wouldn't be surprised that it failed.

At that mileage alternator slip rings will be worn out in addition to the brushes. With regulator replacement you get new brushes. But new slip rings require rebuild of the alternator since they are on the shaft.

Efthreeoh · 01-19-2019, 12:51 PM

Quote:

Originally Posted by PhaseP

At that mileage alternator slip rings will be worn out in addition to the brushes. With regulator replacement you get new brushes. But new slip rings require rebuild of the alternator since they are on the shaft.

The way I looked at it was the alternator lives in a very harsh environment including heat, dirt, water, and oil deposits. After several hundred thousand miles, while it may still be functioning, replacing just a failed voltage regulator doesn't reduce the wear and tear the rest of the alternator has on it. For the time investment to replace the voltage regulator, or remove the alternator for testing, it makes sense to spend a few hundred dollars more and just refresh the unit in its entirety.

lowrydr310 · 01-20-2019, 12:39 PM

I pulled the battery and learned that it's 8 years old! Still tested ok with a load test so I'll keep using it for now but I'm prepared to buy a new one very soon.

I removed the alternator and disassembeled it and found that one of the brushes is shot, not making contact with the slip ring. The corresponding slip ring is also worn. I could still polish it and get away just replacing the brushes, however there is some lateral play in the bearing so they will need to be replaced.

I ordered a cheapo remanufactured alternator that should be here this week ($120, not expecting top quality). I'll use that for now but I plan to rebuild my Valeo unit and swap it out once it's ready.

Rock Auto lists a Denso alternator for my car but like everything else in their catalog parts fitment is a mess for the 2006 325i E90 since they often list parts for the 2006 325Ci which is an E46. I liked the idea of getting a Denso replacement, but that is for the E46 so I went with something else.

mweisdorfer · 01-21-2019, 08:57 PM

I'm pretty sure Bosch makes the OEM alternator. You might be able to save a few $$ buy getting a Bosch vs getting a Bosch with the BMW sticker on it. 😉

335i -

https://www.fcpeuro.com/products/bmw-alternator-al0850x

328 -

https://www.fcpeuro.com/products/bmw...-x5-x3-al0841x

Lifetime warranty-

lowrydr310 · 01-21-2019, 10:42 PM

Quote:

Originally Posted by mweisdorfer

I'm pretty sure Bosch makes the OEM alternator. You might be able to save a few $$ buy getting a Bosch vs getting a Bosch with the BMW sticker on it. 😉

335i -

https://www.fcpeuro.com/products/bmw-alternator-al0850x

328 -

https://www.fcpeuro.com/products/bmw...-x5-x3-al0841x

Lifetime warranty-

The 06 325 OEM is a 180 amp Valeo unit.

I bought new bearings, brushes, and slip rings for around $25 and I'm rebuilding it myself. I already disassembled it and cleaned it, ready to rebuild once the parts arrive. It's too good to return for a $20 core charge. It was pretty obvious that the worn brushes were the issue. I found a Valeo branded voltage regulator for $40 but I'm going to see if the original one still works before replacing it.

PhaseP · 01-22-2019, 08:10 PM

I have a 180A Valeo too, 06 325XI. My slip rings and brushes died early once they had been dosed with engine oil from due to my mistake with oil filter cap. I rebuild it at that time, by a kit from Ebay. And following these videos:

The only problem a few years later one of replacement brushes died. I think it was too soft. Bought new voltage regulator that comes with original brushed, still good.

JonEQuest · 07-27-2020, 10:44 PM

I hate to revive an old thread but I have a 1 year old battery and was getting 2E97 error code occasionally. So far I replaced the brushes and regulator and still got the code. Since then I have replaced the entire alternator with the proper one and even returned the first one to get one with the proper one way clutch pulley. I did all this for nothing. I STILL GET 2E97 generator errors very often. Definitely after a few WOT pulls I will find that code in my JB4. Any idea what could cause it? I have freshened up the old alternator, then swapped in a whole new alternator and the only thing I have accomplished is I now have a shinier alternator.

gbalthrop · 07-28-2020, 02:47 PM

Quote:

Originally Posted by JonEQuest

... was getting 2E97 error code occasionally. So far I replaced the brushes and regulator and still got the code. Since then I have replaced the entire alternator with the proper one and even returned the first one to get one with the proper one way clutch pulley. I did all this for nothing. I STILL GET 2E97 generator errors very often...

What Scan Tool or Diagnostic Software do you have available? What DEFINITION of that code is provided by the Tool? Do you have any simple scan tool that can read P-codes?

See the discussion in Post #3 above in this thread. There are 4 different possible definitions (and separate P-codes) for "2E97" Hex-code.

What make, Model & Part# are the OLD alternator you replaced, AND the new Alternator you replaced it with? What was the Part# of the Voltage Regulator you installed as a replacement? Did your vehicle come from factory with Bosch 180 Amp Alternator? Were Voltage Regulator & Replacement Alternator same spec?

NONE of the four possible definitions for 2E97 suggest a Voltage issue, but have you tried observing System Voltage as you drive using Hidden Menu 9.00 (also described in Post #3)? Does any warning light appear on Instrument Cluster (Yellow or Red Battery)? Any OTHER Fault Codes than 2E97? May be a "JB4 Thing" or some other issue on the BSD Bus, which includes the IBS, Coolant Pump & OZS, all wired to the DME along with Alternator.

George

type-dRew · 08-06-2020, 10:18 PM

I've always has low charging voltage. Low 13s, occasionally high 12s in summer heat. In winter it will get above 14. Unsure why temp makes a difference.

I've never replaced the battery, alternator or any part of the charging system. Car has always worked fine.

Was doing A lot of work and maintenance to the car and decided I'll use a new regulator and since everything works fine, that'll probably help my seemingly low voltage issue.

Anyway, stock one was wore our, brushes almost completely gone. New one goes in. And. Same state of charge. No change.

Only difference now, I get a '2e97 DME; Generator'. Charges 'fine' same as before and have driven 250 miles with this code. No problems.

What the heck does it need? Was thinking I'd start with a battery since it's pretty old as is. But still weird.

IllSic_Design · 08-06-2020, 10:24 PM

Quote:

Originally Posted by type-dRew

I've always has low charging voltage. Low 13s, occasionally high 12s in summer heat. In winter it will get above 14. Unsure why temp makes a difference.

I've never replaced the battery, alternator or any part of the charging system. Car has always worked fine.

Was doing A lot of work and maintenance to the car and decided I'll use a new regulator and since everything works fine, that'll probably help my seemingly low voltage issue.

Anyway, stock one was wore our, brushes almost completely gone. New one goes in. And. Same state of charge. No change.

Only difference now, I get a '2e97 DME; Generator'. Charges 'fine' same as before and have driven 250 miles with this code. No problems.

What the heck does it need? Was thinking I'd start with a battery since it's pretty old as is. But still weird.

The new regulators seem to cause this code(atleast for the people that only had this code pop up after VR replacement). Multiple people(me included) that have changed theirs out with the newer version that FCPeuro sells(there's even a review/comment on their site about it) all seem to get the 2E97 code afterwards. I ended up getting a reman'd Bosch and the code went away after throwing in a new alt.

I did some searching and I guess there was a software update for the DME because of this issue, seems the DME was being too sensitive with the readings from the voltage reg or something. I don't know for sure, just what someone stated on here.

type-dRew · 08-06-2020, 10:31 PM

Quote:

Originally Posted by IllSic_Design

Quote:

Originally Posted by type-dRew

I've always has low charging voltage. Low 13s, occasionally high 12s in summer heat. In winter it will get above 14. Unsure why temp makes a difference.

I've never replaced the battery, alternator or any part of the charging system. Car has always worked fine.

Was doing A lot of work and maintenance to the car and decided I'll use a new regulator and since everything works fine, that'll probably help my seemingly low voltage issue.

Anyway, stock one was wore our, brushes almost completely gone. New one goes in. And. Same state of charge. No change.

Only difference now, I get a '2e97 DME; Generator'. Charges 'fine' same as before and have driven 250 miles with this code. No problems.

What the heck does it need? Was thinking I'd start with a battery since it's pretty old as is. But still weird.

The new regulators seem to cause this code(atleast for the people that only had this code pop up after VR replacement). Multiple people(me included) that have changed theirs out with the newer version that FCPeuro sells(there's even a review/comment on their site about it) all seem to get the 2E97 code afterwards. I ended up getting a reman'd Bosch and the code went away after throwing in a new alt.

I did some searching and I guess there was a software update for the DME because of this issue, seems the DME was being too sensitive with the readings from the voltage reg or something. I don't know for sure, just what someone stated on here.

I have the number listed on their website shown as a superseded number that came out and the new number that they sell here

Wish I would have combed through the reviews first. But it feels dumb to put the old one back in. Maybe I can find a nos unit with my part number somewhere.

I'd rather not replace a working alternator just to kill a code that isn't causing problems, or even a cel at this point

IllSic_Design · 08-06-2020, 10:38 PM

Yeah my OE VR was the same part number, and I agree about buying a new alt. It's costly, I only did it because I was already having charging/battery issues so I didn't want to even worry about that code or the Alt.

fazman · 02-18-2021, 12:44 AM

Quote:

Originally Posted by type-dRew

I have the number listed on their website shown as a superseded number that came out and the new number that they sell here

Wish I would have combed through the reviews first. But it feels dumb to put the old one back in. Maybe I can find a nos unit with my part number somewhere.

I'd rather not replace a working alternator just to kill a code that isn't causing problems, or even a cel at this point

I just did this same VR job on my n54. I had the original VR that seemed like one brush was longer than the other. The original part numbers for the new and the old were the exact same as the one in your pictures. I was getting the 2e97 before and after the VR replacement with the new unit. I got my new part from FCPEuro about a year ago but had no time to install it till just now. My issue in INPA was saying:
P324A - Type unplausibel
Generator 14.30 V 14.4 V
Battery 13.82V 13.82V

I have also been getting 2DED codes for a long while P160F but not sure if they are relate? The car does charge and drive just fine. the Kombi shows charging voltage of about 13.8v-14.3v while driving and I have an AGM coded/registered battery since 2014

01-18-2019, 09:48 PM	#1
lowrydr310 Robot 1661 Rep 2,169 Posts Drives: 2006 330i, 2007 E93 335i Join Date: Apr 2013 Location: Souhtrne Califniora iTrader: (0)	2E97 Alterntor Issue When I started my car this morning I got a red battery warning on the center display along with a "Charging system malfunction" message on my iDrive display. I was about to move my kids to my wife's car but the warning went away after a moment so I kept them in the car and drove them to school. I drove 10 minutes without issue, shut the car off to walk my kids into school, restarted the car and drove home. As soon as I pulled in my driveway the red battery icon appeared again along with the same charging malfunction indicator. I immediately hooked up my laptop and there's a 2E97 code set in DME/DDE, indicating an alternator problem. I looked at the freeze frame data in INPA and it indicates only 11.88V were measured. I haven't begun much diagnostic work yet because I've been busy today, but I wanted to check and see if there's anything specific I should be looking at. Is it just as simple as a bad/failed alternator? As far as I can tell it's the original alternator with 225K miles on it, and if true I wouldn't be surprised that it failed. I can't find any service records from the past ownership (have some but not all records) indicating any alternator replacement and I can see a BMW logo on the side of the alternator. Coincidentally it's been raining pretty heavily all week (and I haven't replaced my under tray yet!). Another coincidence is just last night I hit a nasty pothole that opened up because of all this rain. I'm not sure if that's related but it's odd that I got the alternator error right after these events. I checked the battery tray and there are no puddles or any other signs of water. The battery terminals are perfectly clean with no corrosion. Visually the alternator looks fine, the power wire is still attached solidly and has no corrosion. Where's the engine ground cable located? I want to check that next. I'm going to measure voltage while running with a multimeter, and then tomorrow I am planning to remove the alternator and battery and get them tested at my local auto parts store.
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01-18-2019, 11:12 PM	#2
Welcome to NBA Jam Is it the shoes!? 3884 Rep 5,112 Posts Drives: (Sold) 2011 E92 335i ZMP 6MT Join Date: Mar 2014 Location: USA iTrader: (1)	The voltage regulator is usually a good start since it's cheap(er) than a full rebuilt alternator. Alternators themselves are fairly robust, but they can fail.
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01-19-2019, 06:11 AM	#4
Efthreeoh General 17267 Rep 18,717 Posts Drives: The E90 + Z4 Coupe & Z3 R'ster Join Date: May 2012 Location: Virginia iTrader: (0)	I'm pretty sure 2E97 is the code I got when my alternator died at 314,000 miles; I'll have to check my book in the car to be sure. My car came up with the red battery light on my way to work. I stopped and scanned the ECU with my Schawben BMW scan tool, which I keep in the car. I restarted and the trouble light was not lit, so I thought it was just a battery issue. The light came back on in about a mile. I repeated that event one more time. The light came back on, I was about 25 miles from home. It was December, cold and raining (heat, lights and wipers). I made it back home and the engine died in the driveway. It wouldn't restart because the trip home consumed the energy in the battery. Not being fancy, about it, I figured the alternator at 314,000 miles went tits up, so I replaced it with a BMW OE unit. Not a wink of trouble since then. The battery went about anther year until it wouldn't hold a charge ample enough to start the engine after just a few days sitting. It was over 7 years old at that point. I too debated whether to check the voltage regulator, etc., but since it takes enough time pull the alternator, I just took a WTF attitude and decided not chasing the voltage regulator was a better use of my time. My 2 cents. __________________ A manual transmission can be set to "comfort", "sport", and "track" modes simply by the technique and speed at which you shift it; it doesn't need "modes", modes are for manumatics that try to behave like a real 3-pedal manual transmission. If you can money-shift it, it's a manual transmission. "Yeah, but NO ONE puts an automatic trans shift knob on a manual transmission." Last edited by Efthreeoh; 01-19-2019 at 12:53 PM..
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01-19-2019, 08:15 AM	#5
Boland01 Lieutenant 149 Rep 460 Posts Drives: 2010 535ix, 2008, 2007 335i Join Date: Sep 2013 Location: Magnolia, TX iTrader: (0)	Our335i did the same thing and was only charging a little over 10 volts. Since you have to take half of the engine off (or it sure seemed like it)I went ahead and just replaced the whole alternator too. 6 months later no issues.
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01-20-2019, 12:39 PM	#8
lowrydr310 Robot 1661 Rep 2,169 Posts Drives: 2006 330i, 2007 E93 335i Join Date: Apr 2013 Location: Souhtrne Califniora iTrader: (0)	I pulled the battery and learned that it's 8 years old! Still tested ok with a load test so I'll keep using it for now but I'm prepared to buy a new one very soon. I removed the alternator and disassembeled it and found that one of the brushes is shot, not making contact with the slip ring. The corresponding slip ring is also worn. I could still polish it and get away just replacing the brushes, however there is some lateral play in the bearing so they will need to be replaced. I ordered a cheapo remanufactured alternator that should be here this week ($120, not expecting top quality). I'll use that for now but I plan to rebuild my Valeo unit and swap it out once it's ready. Rock Auto lists a Denso alternator for my car but like everything else in their catalog parts fitment is a mess for the 2006 325i E90 since they often list parts for the 2006 325Ci which is an E46. I liked the idea of getting a Denso replacement, but that is for the E46 so I went with something else.
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01-21-2019, 08:57 PM	#9
mweisdorfer Major General 1903 Rep 6,968 Posts Drives: 2007 Black/Black 335i e90 Join Date: Apr 2011 Location: Holly, MI iTrader: (0) Garage List 2007 BMW E90 335i [0.00] 2008 bmw x5 [0.00]	I'm pretty sure Bosch makes the OEM alternator. You might be able to save a few $$ buy getting a Bosch vs getting a Bosch with the BMW sticker on it. 😉 335i - https://www.fcpeuro.com/products/bmw-alternator-al0850x 328 - https://www.fcpeuro.com/products/bmw...-x5-x3-al0841x Lifetime warranty-
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01-22-2019, 08:10 PM	#11
PhaseP Colonel 1007 Rep 2,108 Posts Drives: 325XI Join Date: May 2010 Location: Earth iTrader: (0)	I have a 180A Valeo too, 06 325XI. My slip rings and brushes died early once they had been dosed with engine oil from due to my mistake with oil filter cap. I rebuild it at that time, by a kit from Ebay. And following these videos: The only problem a few years later one of replacement brushes died. I think it was too soft. Bought new voltage regulator that comes with original brushed, still good.
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07-27-2020, 10:44 PM	#12
JonEQuest Captain 245 Rep 612 Posts Drives: 2008 335i Convertible 2007 335 Join Date: Jul 2018 Location: USA iTrader: (0)	I hate to revive an old thread but I have a 1 year old battery and was getting 2E97 error code occasionally. So far I replaced the brushes and regulator and still got the code. Since then I have replaced the entire alternator with the proper one and even returned the first one to get one with the proper one way clutch pulley. I did all this for nothing. I STILL GET 2E97 generator errors very often. Definitely after a few WOT pulls I will find that code in my JB4. Any idea what could cause it? I have freshened up the old alternator, then swapped in a whole new alternator and the only thing I have accomplished is I now have a shinier alternator.
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08-06-2020, 10:18 PM	#14
type-dRew Major 641 Rep 1,245 Posts Drives: 2009 335i xDrive Join Date: Feb 2019 Location: Newport MI iTrader: (0)	I've always has low charging voltage. Low 13s, occasionally high 12s in summer heat. In winter it will get above 14. Unsure why temp makes a difference. I've never replaced the battery, alternator or any part of the charging system. Car has always worked fine. Was doing A lot of work and maintenance to the car and decided I'll use a new regulator and since everything works fine, that'll probably help my seemingly low voltage issue. Anyway, stock one was wore our, brushes almost completely gone. New one goes in. And. Same state of charge. No change. Only difference now, I get a '2e97 DME; Generator'. Charges 'fine' same as before and have driven 250 miles with this code. No problems. What the heck does it need? Was thinking I'd start with a battery since it's pretty old as is. But still weird. Attached Images __________________ 2009 335i xDrive AT / 177k+ miles PSP 750ic / Fuel-It! Stage 1 / BMS CP / Sutphin Tuning / RFP E50 11.61 @ 117.5 New setup; Covid 19Ts on RFP 93 + ARM inlets, dp, VTT cp and PSP outlets
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08-06-2020, 10:38 PM	#17
IllSic_Design Colonel 2123 Rep 2,758 Posts Drives: 09 E92 335i Join Date: Jun 2016 Location: Northern California iTrader: (1)	Yeah my OE VR was the same part number, and I agree about buying a new alt. It's costly, I only did it because I was already having charging/battery issues so I didn't want to even worry about that code or the Alt.
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