[andrewd1452]

Recently Ive had a crazy amount of electrical problems happening with my 2011 335i, Ive been trying to figure it out but I need some help :/ Is were anybody else out there that has had any of these problems and figured out how to fix them? Its driving me crazy lol

It all started with these codes:
-DME active codes-
29D0- Intake air temperature sensor, electrical: Short circuit to B+
3446- BSD, message; oil condition sensor: missing
378F- BSD, message; electric coolant pump: missing
3847- Generator, Kommunication: Bus-Fehler
38A4- BSD, Message; intelligent battery sensor (IBS): Missing
-DME shadow (Inactive) codes-
2BDE- Fuel high pressure on enabling of injection: pressure too low
2BF0- German Language
(Ive always had the inactive fuel pressure codes)

and now all of these codes are coming up in addition to the other codes:
2C3E- Quantity control valve, activation: Short circuit to earth
2C58- Charging Pressure control: Switch-Off as consequence
2CA2- Wastegate valve: Activation: Short circuit to earth
2D0C- Oxygen sensor heating before catalytic converter, activation: Short circuit to earth
2D10- Oxygen sensor heating after catalytic converter, activation: Short circuit to earth
332E- Terminal 87_1: No voltage

The first set of faults caused my oil level sensor to not work and my water pump to make a very loud buzzing noise while the car was running and for almost a minute after shutting the car off, but it didn’t do it every time I drove. The weird thing is, whenever I would clear the codes, the buzzing would stop and my oil level sensor would work again, until the codes came back. My turbo seals went out and the oil feed line is leaking, so I just assumed the connectors got some oil on them which is causing them to short. Im swapping my turbo with a new Pure STG1 within the next 1-2 weeks, so I was going to check all the connections then and see if cleaning them would fix it.

I uploaded some videos onto youtube (

-

-

-

). FYI, the loud tapping/ clicking noise is my foot tapping the gas pedal so that it doesn't die, I didn't realize it was that loud when I was recording. They show the water pump buzzing that started about a week ago, and all the new issues like long crank/ slow start, rough idle, limp mode/ half power warning, MHD fault codes and MHD monitoring gauge data. One of the videos shows that my Rail Pressure Mean PSI is at 92.8, which is incredibly too low, does that mean my HPFP went out? Is there any way to test the HPFP? And would the HPFP going out possibly be the cause for all of the new set of fault codes? I have a multimeter, so I can test using that, im just not sure exactly what to test and how.
Or could this be battery related? It has a new that was manufactured in August 2017, so I assume the chevy dealership I bought it from, January of this year, put a new one in, im wondering if they even registered it. Is there a way to check if its been registered, and can you register a battery after its been in the car for 10ish months?

The second set of faults didnt start happening until I unplugged the IBS sensor from the distribution block on the positive terminal of the battery. Does anybody know where terminal 87_1 is? From my research, I believe it is in a relay, but Im not sure where it is and how it can be tested. Ive been researching this for several hours over the past few days and havent found any solid answers. I took out the battery and checked all the connections back there and cleaned them, but I still have these problems.

Heres a few things I found about terminal 87 that I think may help find some answers:
-If Terminal 15 at the IBS and Terminal 15 via the BSD are not equal, a fault is indicated in the BSD line or an IBS Fault.
-The DME/DDE controls terminal*87 via a relay in the E-box. Terminal*87 is switched on as soon as terminal*15 is switched on. After terminal*15 has been switched off, terminal*87 is switched off by the DME/DDE with a slight delay. No control units are supplied by terminal*87.

[weehe126]

Check your battery voltage. When these cars have low batter power they have crazy issues long before the car wont start. If charging/replacing the batter still results in a dead batter, the 3847 code means you probably have a bad alternator.

[andrewd1452]

Originally Posted by weehe126

Check your battery voltage. When these cars have low batter power they have crazy issues long before the car wont start. If charging/replacing the batter still results in a dead batter, the 3847 code means you probably have a bad alternator.

I checked directly at the battery, when the car was off, with a multimeter and it was 11.86v. My MHD shows around 13.94-14.24v during idle/driving, do these numbers sound normal? Ill charge it up tomorrow and see if anything changes

[DriveBikeRun]

Check out the thread below. Several of us with 2011 N55s are getting the BSD codes. Be careful just replacing parts that *seem* like they could be the problem as others have tried that without success. No resolution yet. You have some other unique codes, so your root cause could certainly be different. But I still think this is worth a read:

Voltage drop to 11.9v randomly https://www.e90post.com/forums/showthread.php?t=1428829

[ptpending]

11.89 ? you battery close to death
if you charge it outside of the car you'll need to registed battery replacement and have ibs connected
if you plan charge battery on car connect ibs sensor back
and if you haven't changed HPFP and water pump before you'll have to do that at least one time

[weehe126]

Originally Posted by andrewd1452

I checked directly at the battery, when the car was off, with a multimeter and it was 11.86v. My MHD shows around 13.94-14.24v during idle/driving, do these numbers sound normal? Ill charge it up tomorrow and see if anything changes

I would charge it back up to 12.7ish and see if that fixes the issue. You do not need to do any coding if charging the batter outside the car. Not sure I trust MHD to read proper voltage at the battery.

[Cory S]

A battery at rest should never read below 12.3V on a VOM. A good battery should hold 12.5-12.6V overnight.

[x99percent]

OP, was there ever a resolution for this?

[andrewd1452]

Originally Posted by x99percent

OP, was there ever a resolution for this?

Yes, it was my water pump. The plastic cracked right above the connector and leaked coolant into it causing it to short out. I replace the thermostat and water pump and haven't had any problems since, I've driven about 5k miles since. Another problem was a 10a fuse for the fuel pump blew(I think it had something to do with the shorting, It blew a few times before I replaced the water pump) and that was causing the low fuel pressure and the rest of the codes. The water pump shorting made it run constantly and that completely drained my battery, I got a new one and don't have any low voltage problems anymore either

[x99percent]

Originally Posted by andrewd1452

Yes, it was my water pump. The plastic cracked right above the connector and leaked coolant into it causing it to short out. I replace the thermostat and water pump and haven't had any problems since, I've driven about 5k miles since. Another problem was a 10a fuse for the fuel pump blew(I think it had something to do with the shorting, It blew a few times before I replaced the water pump) and that was causing the low fuel pressure and the rest of the codes. The water pump shorting made it run constantly and that completely drained my battery, I got a new one and don't have any low voltage problems anymore either

Thanks, this will likely save me a TON of diag time.

[andrewd1452]

Originally Posted by x99percent

Thanks, this will likely save me a TON of diag time.

No problem. Did you have any other questions that I didn't answer? I spent a lot of time researching it, so I may be able to help you further. Just let me know!

[Atoraya335]

Originally Posted by andrewd1452

Recently Ive had a crazy amount of electrical problems happening with my 2011 335i, Ive been trying to figure it out but I need some help :/ Is were anybody else out there that has had any of these problems and figured out how to fix them? Its driving me crazy lol

It all started with these codes:
-DME active codes-
29D0- Intake air temperature sensor, electrical: Short circuit to B+
3446- BSD, message; oil condition sensor: missing
378F- BSD, message; electric coolant pump: missing
3847- Generator, Kommunication: Bus-Fehler
38A4- BSD, Message; intelligent battery sensor (IBS): Missing
-DME shadow (Inactive) codes-
2BDE- Fuel high pressure on enabling of injection: pressure too low
2BF0- German Language
(Ive always had the inactive fuel pressure codes)

and now all of these codes are coming up in addition to the other codes:
2C3E- Quantity control valve, activation: Short circuit to earth
2C58- Charging Pressure control: Switch-Off as consequence
2CA2- Wastegate valve: Activation: Short circuit to earth
2D0C- Oxygen sensor heating before catalytic converter, activation: Short circuit to earth
2D10- Oxygen sensor heating after catalytic converter, activation: Short circuit to earth
332E- Terminal 87_1: No voltage

The first set of faults caused my oil level sensor to not work and my water pump to make a very loud buzzing noise while the car was running and for almost a minute after shutting the car off, but it didn’t do it every time I drove. The weird thing is, whenever I would clear the codes, the buzzing would stop and my oil level sensor would work again, until the codes came back. My turbo seals went out and the oil feed line is leaking, so I just assumed the connectors got some oil on them which is causing them to short. Im swapping my turbo with a new Pure STG1 within the next 1-2 weeks, so I was going to check all the connections then and see if cleaning them would fix it.

I uploaded some videos onto youtube (

-

-

-

). FYI, the loud tapping/ clicking noise is my foot tapping the gas pedal so that it doesn't die, I didn't realize it was that loud when I was recording. They show the water pump buzzing that started about a week ago, and all the new issues like long crank/ slow start, rough idle, limp mode/ half power warning, MHD fault codes and MHD monitoring gauge data. One of the videos shows that my Rail Pressure Mean PSI is at 92.8, which is incredibly too low, does that mean my HPFP went out? Is there any way to test the HPFP? And would the HPFP going out possibly be the cause for all of the new set of fault codes? I have a multimeter, so I can test using that, im just not sure exactly what to test and how.
Or could this be battery related? It has a new that was manufactured in August 2017, so I assume the chevy dealership I bought it from, January of this year, put a new one in, im wondering if they even registered it. Is there a way to check if its been registered, and can you register a battery after its been in the car for 10ish months?

The second set of faults didnt start happening until I unplugged the IBS sensor from the distribution block on the positive terminal of the battery. Does anybody know where terminal 87_1 is? From my research, I believe it is in a relay, but Im not sure where it is and how it can be tested. Ive been researching this for several hours over the past few days and havent found any solid answers. I took out the battery and checked all the connections back there and cleaned them, but I still have these problems.

Heres a few things I found about terminal 87 that I think may help find some answers:
-If Terminal 15 at the IBS and Terminal 15 via the BSD are not equal, a fault is indicated in the BSD line or an IBS Fault.
-The DME/DDE controls terminal*87 via a relay in the E-box. Terminal*87 is switched on as soon as terminal*15 is switched on. After terminal*15 has been switched off, terminal*87 is switched off by the DME/DDE with a slight delay. No control units are supplied by terminal*87.

I have the same codes you have but I have no idea what is it ??

[andrewd1452]

Originally Posted by Atoraya335

I have the same codes you have but I have no idea what is it ??

This was my solution, it was the water pump. I'd look at yours and see if there's any coolant in the water pump connector, causing a short and the codes. The plastic on the water pump is prone to cracking and leaking right into the connector, causing all of those problems

Originally Posted by x99percent

OP, was there ever a resolution for this?

Yes, it was my water pump. The plastic cracked right above the connector and leaked coolant into it causing it to short out. I replace the thermostat and water pump and haven't had any problems since, I've driven about 5k miles since. Another problem was a 10a fuse for the fuel pump blew(I think it had something to do with the shorting, It blew a few times before I replaced the water pump) and that was causing the low fuel pressure and the rest of the codes. The water pump shorting made it run constantly and that completely drained my battery, I got a new one and don't have any low voltage problems anymore either

[liftrichh]

I'm having the same problem. Replaced the alternator and battery. Registered the battery thru mhd but still have this voltage light popping on. I made sure that the ibs and all the cords were installed properly. This problem occurred when I installed my precision raceworks coils. I checked over and over but everything is installed correctly. Can you help me please guys. Thank you

[andrewd1452]

Originally Posted by liftrichh

I'm having the same problem. Replaced the alternator and battery. Registered the battery thru mhd but still have this voltage light popping on. I made sure that the ibs and all the cords were installed properly. This problem occurred when I installed my precision raceworks coils. I checked over and over but everything is installed correctly. Can you help me please guys. Thank you

Check the connector on your water pump. Unplug it and see if theres any coolant or oil inside of it. My water pump cracked causing coolant to get in there and short out the whole system. All of those components / sensors run to the DME through the same BSD line, so when one shorts out and stops working, they all do. I believe the shorting of the water pump causes it to run even after you turn it off, so thats what is draining your battery. Replacing my water pump solved every single one of those issues for me, so that would be my first recommendation.

[liftrichh]

Originally Posted by andrewd1452

Check the connector on your water pump. Unplug it and see if theres any coolant or oil inside of it. My water pump cracked causing coolant to get in there and short out the whole system. All of those components / sensors run to the DME through the same BSD line, so when one shorts out and stops working, they all do. I believe the shorting of the water pump causes it to run even after you turn it off, so thats what is draining your battery. Replacing my water pump solved every single one of those issues for me, so that would be my first recommendation.

I just recently replaced the water pump myself like a week ago. Do I check connections on the water pump or the thermostat itself?

[andrewd1452]

Originally Posted by liftrichh

I just recently replaced the water pump myself like a week ago. Do I check connections on the water pump or the thermostat itself?

Sorry for the late reply, just saw your post.
The connector plugged directly into the water pump is what I would try first. Grab some CRC QD Electronic Cleaner and try spraying down the connector to clean it out and then try clearing the codes and see if it pops up again. You could also try re-installing your stock coils, if possible, and see if it goes away. Im still on stock coils, so Im not sure how aftermarket ones would effect your battery, but its possible. It could also be your alternator or alternators voltage regulator aren't the correct specs

[liftrichh]

Thank you

[afy511]

I have the same code read by MHD
3446
378F
3847
38A4

Car was dead for like 7 months, after that i recharged the AGM battery connecting to my 2nd X5.
Battery reads 12.2 - 12.5 even after a day without starting the car. While engine ON the voltage is between 13.7 - 14.something
My water pump is working normally(i have checked by opening the reservoir while idle) and after this error code pops up the oil level cannot be viewed from the iDrive. Coolant temperature remains 100 degree Celcius or around 95 while running.
I also have transmission issue after transmission repair. It slips to neutral sometimes after heating up. Transmission oil temperature is between 85-less than 100 while running
4E84
4E98

Any help would be appreciated.

[afy511]

liftrichh Did you solve yours

[KaneOG]

Op I have a question that maybe you could help with. So yesterday my wires to my water pump came loose and got ate up by the belt. I fixed the 2 tires and these codes came up after my quick deposit on the side of the road. My water pump and Tstat work fine but the car is stuck in limp mode. I've been told to check fuses but I haven't found any blown 20a fuses. Do you have any knowledge that could help?

[anjuna]

Had a very similar issue (Like, 30 psi fuel pressure instead of like 1800psi) yesterday that presented while driving on a tollway, forcing me to left-shoulder and have fun. Gotta say, that sucks dick in the 100°F Texas weather and wasn't really enjoyable on a 70-80mph tollway.

aaaaaaaaaaaanyyyyway - ended up being corrosion on the fuse and/or the terminal block. By removing the fuse and adding it back, I was back in business.

Check yer fuses. Pull and reseat them too.

Also, the "short to ground" on oxy sensor could be a cable hitting a downpipe or something else really hot.

I know I get a "short A to B" or something on my MAF when running mafless, FWIW.