A complex voltage problem not for the feint of heart.
10-26-2017 | 06:49 PM
#11
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Joined: Sep 2016
Posts: 10
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From: Arkansas
My Ride: 08' 535i Sport Package S/A trans
Model Year: 2008
Recently my rear passenger comfort access door handle started misbehaving and would constantly re-lock the car when it was parked. This of course will drain the battery and I would get the high battery drain message upon the next startup. When it became worse, the date and time would reset. So I disconnected that door handle and the problem went away.
You say comfort access fails to work. Is that just on one door? Try other doors first, if they work, then you've found the bad door.
Just a thought anyway. Our cars have so many electronics, your problem could be anything.
You say comfort access fails to work. Is that just on one door? Try other doors first, if they work, then you've found the bad door.
Just a thought anyway. Our cars have so many electronics, your problem could be anything.
You or your mechanic can chase which circuit is the offending draw by going circuit by circuit with an ammeter. As a first pass you can go fuse by fuse with the key off without the vehicle asleep (~16 min after last action - door open, etc). See where the big draw is - most will be ~0 or so. There will be few with 1+ amp draw, so you can then focus on them. You just need to revisit each higher draw circuit but now have to wait until the car goes to sleep. It's best to avoid connecting the meter in series because they generally don't have much amperage throughput (ie, you'll pop the fuse in the meter) but I'd guess your mech will already know that.
It could also be telling if there is not drop off from pre- to post- sleep voltage draw. That would indicate to me a module is not shutting down. At that point you should be able to look at a wiring diagram for that circuit to narrow down where to look. The ISTA/D tool does a good job of compiling that info together (including where to physically look in the car).
Regards,
Andy
07 530xiT 6MT
It could also be telling if there is not drop off from pre- to post- sleep voltage draw. That would indicate to me a module is not shutting down. At that point you should be able to look at a wiring diagram for that circuit to narrow down where to look. The ISTA/D tool does a good job of compiling that info together (including where to physically look in the car).
Regards,
Andy
07 530xiT 6MT
First thing you need to do is a load test on the battery. Drive the car for a while, disconnect the battery terminals and check voltage and do a load test,leave them off till the morning. Repeat the process,if it reads lower than a normal reading, change out the battery.
Change out the battery.. I had the exact same problem. I took my battery out and had it deep cycle tested on the battery machine at my dealership. Passed the test..
Everyone insisted my battery was fine. I replaced it anyway and all of my issues went away instantly.
Just make sure you replace it with the exact same battery that's in the car otherwise you'll have to get it programmed.
Everyone insisted my battery was fine. I replaced it anyway and all of my issues went away instantly.
Just make sure you replace it with the exact same battery that's in the car otherwise you'll have to get it programmed.
This car is very complex and most just say to start replacing sensors. A battery can have good volts, but hold low amps. These cars are very smart and can detect the slightest drop,, so when a code is present, and a random one pops up, it's a good indication the battery is nearing it's full duty cycle. This happens so frequently and often overlooked. The heavy ground strap can also cause the same issue being exposed to the elements.
Thank you all. I'll keep you apprised.
11-08-2017 | 07:14 PM
#12
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Joined: Nov 2017
Posts: 2
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From: New Zealand
My Ride: 2007 550i
The battery sensor, oil condition sensor, generator (alternator), and water pump all communicate via the Bit Serial Data (BSD) Interface. Problem or a disconnect in one item can trigger fault codes in the others. A fault in the BSD line or a module on it can affect charging and alternator output, odd changes in oil service intervals, and strange water pump behaviour. I'm an armchair expert only, but I think you can narrow it down to something on the BSD...
11-19-2017 | 05:36 PM
#13
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Joined: Sep 2016
Posts: 10
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From: Arkansas
My Ride: 08' 535i Sport Package S/A trans
Model Year: 2008
Good day everyone. Here's some news.
I took the car to advance auto to get the battery/alternator tested before buying a new one of either. No useful results there as both checked out within spec.
I did most everything suggested to me above, checking fuses, connections, looking for other places water may have gotten in, etc...
After a week I took it to my indy again. Explained how it's been acting and left it overnight. After 8 hours of diag they still aren't sure whats up. They said that they don't actually have the parts to keep going. They would have to order each thing that it could be one at a time to test each part and hopefully find it quickly. They didn't give me technical details aside from that something is indeed causing a draw on the battery.
They suggested I take it to the local dealer and have a specific tech look into it. They have a good relationship with the dealer and think that the dealer will likely have parts lying around to put on and test without actually charging me. That seems dubious but I trust that the dealer will make it clear to me what's possible when I take it over tomorrow.
Anyway, there's also a new symptom. It's missing at low load throttle. 2k-3100...so weird. Not constant either. Happens sometimes but not others. Currently no misfire codes, though they've shown up before. I've put a new tank of fuel in so not that. Indy thinks it may be related to the electrical issues getting worse.
In any case. I'll update when I know more.
I took the car to advance auto to get the battery/alternator tested before buying a new one of either. No useful results there as both checked out within spec.
I did most everything suggested to me above, checking fuses, connections, looking for other places water may have gotten in, etc...
After a week I took it to my indy again. Explained how it's been acting and left it overnight. After 8 hours of diag they still aren't sure whats up. They said that they don't actually have the parts to keep going. They would have to order each thing that it could be one at a time to test each part and hopefully find it quickly. They didn't give me technical details aside from that something is indeed causing a draw on the battery.
They suggested I take it to the local dealer and have a specific tech look into it. They have a good relationship with the dealer and think that the dealer will likely have parts lying around to put on and test without actually charging me. That seems dubious but I trust that the dealer will make it clear to me what's possible when I take it over tomorrow.
Anyway, there's also a new symptom. It's missing at low load throttle. 2k-3100...so weird. Not constant either. Happens sometimes but not others. Currently no misfire codes, though they've shown up before. I've put a new tank of fuel in so not that. Indy thinks it may be related to the electrical issues getting worse.
In any case. I'll update when I know more.
11-23-2017 | 08:22 PM
#14
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Joined: Sep 2016
Posts: 10
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From: Arkansas
My Ride: 08' 535i Sport Package S/A trans
Model Year: 2008
Quick and simple update. I've got an appointment Monday at BMW. Between now and then I'm going to try and figure out what clamp meter to get and grab one tomorrow....put it on and start pulling fuses to figure out what might mend the problem. The missing seems to have quieted down a bit. Still shows up occasionally but it's not getting any worse for sure.
11-29-2017 | 05:32 PM
#15
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Joined: Sep 2016
Posts: 10
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From: Arkansas
My Ride: 08' 535i Sport Package S/A trans
Model Year: 2008
So...news to all of you...the car came back from the dealer today...with all the same faults it's been giving me.
Apparently I wasn't clear enough despite saying the words "I need someone to look into the BSD line" they heard "Water may have gotten in the trunk in the past and caused some of the issues" and went with the standard BMW water in the trunk fix.
They removed all the wiring from the bottom of the trunk and relocated it to the side of the trunk which is lovely of them and all...they even replaced my MULF and TPMS (Neither of which seem to have been coded I guess cause they're not working in the car, going to post seperately about that...maybe I need to do something...) but seemed to miss that the car was throwing all these codes at them....
So I'm pretty frustrated honestly. I'm going to call them in the morning about the two new sensors in the trunk that aren't seemingly talking to the PCM.
The shop foreman and I chatted after I realized none of the codes were gone and were coming back as soon as I deleted them...
He said that the faults aren't going to get any worse, that the BSD line isn't going to cause more headaches than the ones I'm already experiencing and in his opinion I'd do well to swap the IBS and see what happens.
He said that despite me unplugging it and still experiencing symptoms that it could STILL be the problem. They've redesigned it multiple times apparently because of all the issues it causes.
SO...I'm going to do these things.
Call BMW in the morning about the sensors not working and ask why..
Buy an IBS sensor and negative battery cable and install it.
Anyone have any other ideas or thoughts about this part of the process?
Apparently I wasn't clear enough despite saying the words "I need someone to look into the BSD line" they heard "Water may have gotten in the trunk in the past and caused some of the issues" and went with the standard BMW water in the trunk fix.
They removed all the wiring from the bottom of the trunk and relocated it to the side of the trunk which is lovely of them and all...they even replaced my MULF and TPMS (Neither of which seem to have been coded I guess cause they're not working in the car, going to post seperately about that...maybe I need to do something...) but seemed to miss that the car was throwing all these codes at them....
So I'm pretty frustrated honestly. I'm going to call them in the morning about the two new sensors in the trunk that aren't seemingly talking to the PCM.
The shop foreman and I chatted after I realized none of the codes were gone and were coming back as soon as I deleted them...
He said that the faults aren't going to get any worse, that the BSD line isn't going to cause more headaches than the ones I'm already experiencing and in his opinion I'd do well to swap the IBS and see what happens.
He said that despite me unplugging it and still experiencing symptoms that it could STILL be the problem. They've redesigned it multiple times apparently because of all the issues it causes.
SO...I'm going to do these things.
Call BMW in the morning about the sensors not working and ask why..
Buy an IBS sensor and negative battery cable and install it.
Anyone have any other ideas or thoughts about this part of the process?
12-07-2017 | 03:54 PM
#16
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Joined: Jan 2012
Posts: 557
Likes: 1
From: Dayton, OH
My Ride: 07 550i Sports Package
Model Year: 2007
Stop wasting your time and just do what everyone has been telling you, replace the battery, that is the easiest test. The money you are spending at the Indy and Dealer could have replaced the battery twice over. Go to Auto Zone get a battery and all your problems will be solved. I did not program my battery and it worked just fine. Also, what is the actual age of your battery you didn't say.
02-27-2018 | 07:52 AM
#17
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Joined: Apr 2014
Posts: 96
Likes: 1
From: New York
My Ride: BMW E60
Model Year: 2004
Engine: E60 M54
One hard fact I have reluctantly learned is regardless what the electrical issue is with these cars..just get a new battery. Can't even count how many times it resolved many of the issues I had. At the very least give it a slow charge.
05-30-2018 | 09:42 AM
#18
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Joined: Sep 2016
Posts: 10
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From: Arkansas
My Ride: 08' 535i Sport Package S/A trans
Model Year: 2008
Just wanted to update everyone.... It was the damn battery.
I finally threw my hands up and took it to the dealer. I told them everything I've mentioned here and they went to testing everything. They found that it needed a battery within a couple hours and the problem hasn't come back since I swapped it(Around 3 months ago).
I finally threw my hands up and took it to the dealer. I told them everything I've mentioned here and they went to testing everything. They found that it needed a battery within a couple hours and the problem hasn't come back since I swapped it(Around 3 months ago).
