550i Limp mode and electrical issues
11-20-2016, 02:35 PM
#1
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550i Limp mode and electrical issues
Folks,
Hope the best and brightest can assist with this strange electrical issue. I'll try to stick to facts so far:
-2008 550i 135k miles
-car went into limp mode early last week on way to work. Got a myriad of errors per the Carly app. Cleared them and car stayed in limp mode with these errors:
-2CF8 Throttle potentiometer sensor
-2CF9 Throttle potentiometer 1
-2CFA Throttle potentiometer 2
-2A6B VVT border electricity supply emergency
-5F77 DME Error
-A559 Terminal Shutdown
-???? Short circuit
-A85F steering column unknown
-While trying to drive the car back home in limp mode, the car starts puking coolant from the overflow tank and I hear a loud screech from under the hood. Check and water pump has seized (this is leading somewhere, keep with me...)
-have the car towed to get water pump fixed and have other issue checked. They think the alternator was possibly overcharging as there were several other faults when they were able to get the car running. They were asking $1500 for this. I decide to do it myself and have the original alt rebuilt by a shop that I've had several rebuilt with zero issues.
-I managed to replace the alt, belts, and tensioners and after restart, car runs super smooth.
-I test drive it for about an hour and check voltages and I'm getting a steady 14.4 volts...I return home.
-I go back to test again and the car seems to be dead. Will not respond to remote to open or comfort access input. I open the door with the key and everything lights up instantly. I assume it's a fluke and test drive, still getting the steady 14.4 volts. On the way back, the car falls into limp mode again with the errors above again.
-I limp it back with it chugging and rattling since i was close to home and look up the codes again and research for about 6 hours (watching football while looking)
-One bimmer tech site states that I have an engine harness failure and requires complete replacement $$$
-Other potential problems are Throttle body harness and throttle body unit replacement
-I go back out to see if I can reset the car and extract more codes and the car is dead again...no response to remote or comfort access inputs. When i open the door, car stays dead.
-I immediately check the battery with a multimeter and it's showing 12.8 volts (after sitting for 6 hours), but no power to anything.
With these issues I'm seeing, it seems I've fried a module of some sort, but it looks like beyond that I still have an issue with the throttle body (unit itself or the harness). Any techs in here have any ideas?
I'm so conflicted because I've just spent about $2k on this POS in the last 3 months and I want to keep it and get most of that back, but these electrical issues are enough for me to just say screw it and abandon it somewhere....
Hope the best and brightest can assist with this strange electrical issue. I'll try to stick to facts so far:
-2008 550i 135k miles
-car went into limp mode early last week on way to work. Got a myriad of errors per the Carly app. Cleared them and car stayed in limp mode with these errors:
-2CF8 Throttle potentiometer sensor
-2CF9 Throttle potentiometer 1
-2CFA Throttle potentiometer 2
-2A6B VVT border electricity supply emergency
-5F77 DME Error
-A559 Terminal Shutdown
-???? Short circuit
-A85F steering column unknown
-While trying to drive the car back home in limp mode, the car starts puking coolant from the overflow tank and I hear a loud screech from under the hood. Check and water pump has seized (this is leading somewhere, keep with me...)
-have the car towed to get water pump fixed and have other issue checked. They think the alternator was possibly overcharging as there were several other faults when they were able to get the car running. They were asking $1500 for this. I decide to do it myself and have the original alt rebuilt by a shop that I've had several rebuilt with zero issues.
-I managed to replace the alt, belts, and tensioners and after restart, car runs super smooth.
-I test drive it for about an hour and check voltages and I'm getting a steady 14.4 volts...I return home.
-I go back to test again and the car seems to be dead. Will not respond to remote to open or comfort access input. I open the door with the key and everything lights up instantly. I assume it's a fluke and test drive, still getting the steady 14.4 volts. On the way back, the car falls into limp mode again with the errors above again.
-I limp it back with it chugging and rattling since i was close to home and look up the codes again and research for about 6 hours (watching football while looking)
-One bimmer tech site states that I have an engine harness failure and requires complete replacement $$$
-Other potential problems are Throttle body harness and throttle body unit replacement
-I go back out to see if I can reset the car and extract more codes and the car is dead again...no response to remote or comfort access inputs. When i open the door, car stays dead.
-I immediately check the battery with a multimeter and it's showing 12.8 volts (after sitting for 6 hours), but no power to anything.
With these issues I'm seeing, it seems I've fried a module of some sort, but it looks like beyond that I still have an issue with the throttle body (unit itself or the harness). Any techs in here have any ideas?
I'm so conflicted because I've just spent about $2k on this POS in the last 3 months and I want to keep it and get most of that back, but these electrical issues are enough for me to just say screw it and abandon it somewhere....
11-20-2016, 03:18 PM
#2
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My Ride: 05 530i M54
Model Year: 05 530i
Engine: 3.0 M54
I see you said there was a short circuit. Your DME is having issues. I would check to see if the fan is working. Do you live in a hot state. It looks to me that the cooling fan on the DME went bad and you drove on it too bad and the DME overheated. Maybe to the state of ruining it. Check the fan that is in the the DME casing under the cabin air filter on the passenger side. You will have to take everyhting out I believe as it sits on the bottom. This should solve these issues (-5F77 DME Error
-A559 Terminal Shutdown -???? Short circuit) if the DME is not ruined.
The other codes looks like a bad throttle harness. At 135K I do see the throttle body having issues unless the car was not taken car of. If you replace something on the system (VVT or sensor a relearn needed to be done).
I hope this helps a little. I think the Alternator rebuild was done prematurely because alternators last a long time unless there is a continuous leak on it. If you did not have lights lite up on the dash then your voltage regulator should of been good as this would of been what would cause a charging issue on the system other than the terminal on the battery (which could be bypassed for testing).
-A559 Terminal Shutdown -???? Short circuit) if the DME is not ruined.
The other codes looks like a bad throttle harness. At 135K I do see the throttle body having issues unless the car was not taken car of. If you replace something on the system (VVT or sensor a relearn needed to be done).
I hope this helps a little. I think the Alternator rebuild was done prematurely because alternators last a long time unless there is a continuous leak on it. If you did not have lights lite up on the dash then your voltage regulator should of been good as this would of been what would cause a charging issue on the system other than the terminal on the battery (which could be bypassed for testing).
11-20-2016, 05:02 PM
#3
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I see you said there was a short circuit. Your DME is having issues. I would check to see if the fan is working. Do you live in a hot state. It looks to me that the cooling fan on the DME went bad and you drove on it too bad and the DME overheated. Maybe to the state of ruining it. Check the fan that is in the the DME casing under the cabin air filter on the passenger side. You will have to take everyhting out I believe as it sits on the bottom. This should solve these issues (-5F77 DME Error
-A559 Terminal Shutdown -???? Short circuit) if the DME is not ruined.
The other codes looks like a bad throttle harness. At 135K I do see the throttle body having issues unless the car was not taken car of. If you replace something on the system (VVT or sensor a relearn needed to be done).
I hope this helps a little. I think the Alternator rebuild was done prematurely because alternators last a long time unless there is a continuous leak on it. If you did not have lights lite up on the dash then your voltage regulator should of been good as this would of been what would cause a charging issue on the system other than the terminal on the battery (which could be bypassed for testing).
-A559 Terminal Shutdown -???? Short circuit) if the DME is not ruined.
The other codes looks like a bad throttle harness. At 135K I do see the throttle body having issues unless the car was not taken car of. If you replace something on the system (VVT or sensor a relearn needed to be done).
I hope this helps a little. I think the Alternator rebuild was done prematurely because alternators last a long time unless there is a continuous leak on it. If you did not have lights lite up on the dash then your voltage regulator should of been good as this would of been what would cause a charging issue on the system other than the terminal on the battery (which could be bypassed for testing).
11-20-2016, 06:03 PM
#4
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Question: if the fan is bad, it seems I would get a code for the e-fan based on my reading some other threads online. I don't have any codes for the fan. If the DME/ECU were bad, I'm thinking I wouldn't be able to communicate with it through the Carly app....however, I can and it answers. Could the IBS cause this problem?
08-04-2022, 06:35 PM
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My Ride: 545 e60
Folks,
Hope the best and brightest can assist with this strange electrical issue. I'll try to stick to facts so far:
-2008 550i 135k miles
-car went into limp mode early last week on way to work. Got a myriad of errors per the Carly app. Cleared them and car stayed in limp mode with these errors:
-2CF8 Throttle potentiometer sensor
-2CF9 Throttle potentiometer 1
-2CFA Throttle potentiometer 2
-2A6B VVT border electricity supply emergency
-5F77 DME Error
-A559 Terminal Shutdown
-???? Short circuit
-A85F steering column unknown
-While trying to drive the car back home in limp mode, the car starts puking coolant from the overflow tank and I hear a loud screech from under the hood. Check and water pump has seized (this is leading somewhere, keep with me...)
-have the car towed to get water pump fixed and have other issue checked. They think the alternator was possibly overcharging as there were several other faults when they were able to get the car running. They were asking $1500 for this. I decide to do it myself and have the original alt rebuilt by a shop that I've had several rebuilt with zero issues.
-I managed to replace the alt, belts, and tensioners and after restart, car runs super smooth.
-I test drive it for about an hour and check voltages and I'm getting a steady 14.4 volts...I return home.
-I go back to test again and the car seems to be dead. Will not respond to remote to open or comfort access input. I open the door with the key and everything lights up instantly. I assume it's a fluke and test drive, still getting the steady 14.4 volts. On the way back, the car falls into limp mode again with the errors above again.
-I limp it back with it chugging and rattling since i was close to home and look up the codes again and research for about 6 hours (watching football while looking)
-One bimmer tech site states that I have an engine harness failure and requires complete replacement $$$
-Other potential problems are Throttle body harness and throttle body unit replacement
-I go back out to see if I can reset the car and extract more codes and the car is dead again...no response to remote or comfort access inputs. When i open the door, car stays dead.
-I immediately check the battery with a multimeter and it's showing 12.8 volts (after sitting for 6 hours), but no power to anything.
With these issues I'm seeing, it seems I've fried a module of some sort, but it looks like beyond that I still have an issue with the throttle body (unit itself or the harness). Any techs in here have any ideas?
I'm so conflicted because I've just spent about $2k on this POS in the last 3 months and I want to keep it and get most of that back, but these electrical issues are enough for me to just say screw it and abandon it somewhere....
Hope the best and brightest can assist with this strange electrical issue. I'll try to stick to facts so far:
-2008 550i 135k miles
-car went into limp mode early last week on way to work. Got a myriad of errors per the Carly app. Cleared them and car stayed in limp mode with these errors:
-2CF8 Throttle potentiometer sensor
-2CF9 Throttle potentiometer 1
-2CFA Throttle potentiometer 2
-2A6B VVT border electricity supply emergency
-5F77 DME Error
-A559 Terminal Shutdown
-???? Short circuit
-A85F steering column unknown
-While trying to drive the car back home in limp mode, the car starts puking coolant from the overflow tank and I hear a loud screech from under the hood. Check and water pump has seized (this is leading somewhere, keep with me...)
-have the car towed to get water pump fixed and have other issue checked. They think the alternator was possibly overcharging as there were several other faults when they were able to get the car running. They were asking $1500 for this. I decide to do it myself and have the original alt rebuilt by a shop that I've had several rebuilt with zero issues.
-I managed to replace the alt, belts, and tensioners and after restart, car runs super smooth.
-I test drive it for about an hour and check voltages and I'm getting a steady 14.4 volts...I return home.
-I go back to test again and the car seems to be dead. Will not respond to remote to open or comfort access input. I open the door with the key and everything lights up instantly. I assume it's a fluke and test drive, still getting the steady 14.4 volts. On the way back, the car falls into limp mode again with the errors above again.
-I limp it back with it chugging and rattling since i was close to home and look up the codes again and research for about 6 hours (watching football while looking)
-One bimmer tech site states that I have an engine harness failure and requires complete replacement $$$
-Other potential problems are Throttle body harness and throttle body unit replacement
-I go back out to see if I can reset the car and extract more codes and the car is dead again...no response to remote or comfort access inputs. When i open the door, car stays dead.
-I immediately check the battery with a multimeter and it's showing 12.8 volts (after sitting for 6 hours), but no power to anything.
With these issues I'm seeing, it seems I've fried a module of some sort, but it looks like beyond that I still have an issue with the throttle body (unit itself or the harness). Any techs in here have any ideas?
I'm so conflicted because I've just spent about $2k on this POS in the last 3 months and I want to keep it and get most of that back, but these electrical issues are enough for me to just say screw it and abandon it somewhere....
i know that the problem you mention is from many years ago. because I have the exact same problem with a 545. I did a search on the internet and found your post and I would like to ask you if you finally fixed it and what the problem was.
thank a lot
Alex
08-06-2022, 11:57 AM
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My Ride: 2008 550i 6-spd; 2007 530i Sport
Model Year: 2008
Alex:
Not sure which of OP's issues you are encountering, but my 2008 550i went into limp mode around the same 135k miles and I found I needed to thoroughly clean the throttle body. Once I did that, everything returned to normal.
Here is a link to my experience; hope it helps. https://www.bimmerforums.com/forum/s...=throttle+body
I can't offer any good advice if you're experiencing his other issues. Good luck
Nick
Not sure which of OP's issues you are encountering, but my 2008 550i went into limp mode around the same 135k miles and I found I needed to thoroughly clean the throttle body. Once I did that, everything returned to normal.
Here is a link to my experience; hope it helps. https://www.bimmerforums.com/forum/s...=throttle+body
I can't offer any good advice if you're experiencing his other issues. Good luck
Nick
