Dead battery, car doesn’t start even with jump starter

M

MihaiDumitrache

Member
Hello everyone,

I have an E89 30i 2011.
I will describe the electrical problems I faced during the last month with the car:

1.After leaving the car parked for a week ( it rained all the time, i think it is an important detail ) I found that the battery went flat. I tried jum starting the car using the terminals under the hood but the car wouldnt start. All the electrical stuff worked ( dials, navigation, lights, signals, electrical seats etc. ) but when I pressed the break peddal and the Strat/stop button the engine wouldnt crank and the navigation display would close and open again.

2. Someone came and took a look at the car and we tested the starter motor. They managed to get it out and tested it. I worked fine. Then we mounted the starter on the car again and they tried to supply current to the starter using a battery. The car managed to crank and the engine started. This made them think that the problem is with the CAS but someone told them that the car should crank even with a messed up CAS module.
After aprox 2 hours of tests they somehow found out that the steering column locking mechanism didnt get any voltage. They dissasembled the whone steering column, blocked the locking mechanism and took the CAS away to reprogram it ( I believe they installed some sort of emulator that bypasses the locking of the steering ). AFTER PUTTING ALL OF THESE BACK IN, THE CAR WORKED PERFECTLY.

3. 2 days after the car was “fixed” I got a battery discarge warning when starting the car. Drove home ( aprox 12 km ) and in the morning ( 10 hours later ) the battery was dead and I had tot start the car with a jump starter.

4. the next time I started the car ( also with the jump starter as it sit for another 10 hours ) the windows, signals and high beam didnt work. Someone told me that the FRM module got messed up.
I kept it running for about 30 minutes, closed it using the key fob ( as the remote didnt work ) and I saw that even after 3 hours there were wome LEDs working inside the car ( the “P” on the gearbox selector, the start stop button and the backlight of the idrive)

5. Took the car to someone else (using a platform ) and they kept it for about one week doing all sorts of tests as I thought that there is something that drains the battery. They mounted the correct battery on the car ( as the one mounted on the car was not the one specified by BMW. The car had a 74Ah non-AGM battery and the car needed a 70Ah AGM. ) and they registered it. Kept the car for another 5-6 days and measured the battery everytime. They also let it parked for a few days and measured the battery and everything was fine.
There was no residual voltage when the car went in sleep mode and I thought that there is problem was solved and the issue was the old battery that was not registered and the car probably didnt charge it appropiately.

6.Got the car back, used it without any problem for a week and parked it for Christmas. After 2 days I wanted to see if it is ok and…….dead. Tried to jump start it and it didnt work. Kept the charger for about 10 minuted and NOTHING….

It snowed during christmas and the car was covered with snow. Now….as I wrote at the beginning of the thread, the similarities with the first time I found the car dead is that there was “water” involved both times. I believe it is possible that water short circuited something and that got the battery to drain…

It is getting me crazy.

Did anyone faced something remotely close to this?

Do you have any suggestions as what can I do to narrow it down and find the source of the problem?

Also…any tips on opening the boot with a dead battery and not being able to jump start the car?
 
So most of the f**k ups that could be done have been done…

To start from scratch ..

You’ll need a decent brand new battery 70ah or 80 AGM..it will need to be coded and registered.,.but you can do that later…

What you’ll need is a decent battery charger to be applied to the charging post in the engine bay

Let it charge for 12 hours +

You MAY have enough juice then to release the boot to put a brand new fully charged battery in

If not you will need to jump lead to the engine bay with a car running…be careful..

That should give you enough power to release the boot to put the new battery in…

In the f**k-ups you and your partners in crime have committed you MAY have frazzled the FRM..fortunately this can be repaired for £50 but it is a bench only fix.

You MAY have frazzled the steering ECU and or the EFB ECU..but let’s get to that later.

Jumping the battery is a big no no and you MAY have blown the main fuse between the battery / engine bay..that’s a big problem..

Once you’ve got things working after a fashion then do a residual current leakage check …

But..you’re a long way from there..

Merry Christmas..
 
Hello and thank you for your message.

I installed an OEM battery on the car 2 weeks ago. It is a 70 Ah AGM battery. They also registered it, as I mentioned in the previous message.

I am just looking for someones possible similar experience with something that can cause the battery to drain. Maybe some water that gets in some places and short circuited something…I dont know. Until everyone gets back to work and I can get it back into a service I wanted to know If i can do some investigations.
 
MihaiDumitrache said:
Hello and thank you for your message.

I installed an OEM battery on the car 2 weeks ago. It is a 70 Ah AGM battery. They also registered it, as I mentioned in the previous message.

I am just looking for someones possible similar experience with something that can cause the battery to drain. Maybe some water that gets in some places and short circuited something…I dont know. Until everyone gets back to work and I can get it back into a service I wanted to know If i can do some investigations.
Click to expand...
The way to find out what the issue is by either subtraction and/or code reader..

With the car shut down you measure the current flow from the battery ..it should be around 7ma with occasional bursts up to 70ma

If it’s greater than this then you disconnect the modules you think most likely that are causing the issue comfort access, Bluetooth etc usually by pulling the fuse…

Fault code reader may show rogue modules also…


Bluetooth , comfort access, FRM are amongst the main culprits
 
Hello again,

I connected the car to a charger and left it there for about 11 hours. Nothing happened. No lights, no dash, nothing.

Is there a way I can open the boot?
 
MihaiDumitrache said:
Hello again,

I connected the car to a charger and left it there for about 11 hours. Nothing happened. No lights, no dash, nothing.

Is there a way I can open the boot?
Click to expand...
What’s the voltage on the battery off load?

What happens when you use a car to power the terminal in the engine bay?

My guess is the battery is dead…if not then one or more fuses are blown..maybe the main non repairable one?
 
B21 said:
What’s the voltage on the battery off load?

What happens when you use a car to power the terminal in the engine bay?

My guess is the battery is dead…if not then one or more fuses are blown..maybe the main non repairable one?
Click to expand...
Hello, thank you for your time,

The voltage measured on the terminals underneath the hood is around 12,2V.

I didnt get to connect another car, I am waiting for my father in law to come and do that because i have a car with start/stop ( G30 540i ) and someone told me in the past that I should avoid using my car as a donor…dont know if its true.

I will check all the fuses tomorow, I didn’t think about that….
 
Meanwhile, Do you know if there is any way I can open the boot? I have the sky hatch, I managed to open it and take the bag out but I cant see any latch to manually open the lock…
 
MihaiDumitrache said:
someone told me in the past that I should avoid using my car as a donor…dont know if its true.
Click to expand...
Don't see any reason to not connect both cars, except your whole car represents a short.

If you do have a cable give it a try.
If connected, you should be able to open the trunk lid. It can't be opened from the inside of your car.
 
MihaiDumitrache said:
Hello, thank you for your time,

The voltage measured on the terminals underneath the hood is around 12,2V.

I didnt get to connect another car, I am waiting for my father in law to come and do that because i have a car with start/stop ( G30 540i ) and someone told me in the past that I should avoid using my car as a donor…dont know if its true.

I will check all the fuses tomorow, I didn’t think about that….
Click to expand...
If you’ve got 12+ v on the front terminal pls measure it when you try and switch the car on ..it could be that the off load voltage is ok but collapses on load..not the first time..

If they’re zero change in volts ie stays at 12v+ then you’ve got one or more fuses blown..
 
Well... I managed to get it running. I found an electrical scheme posted on the forum and figured out that:
a. If the jump starter didn't drain while connected to the terminals under the hood
b. The voltage on the battery was ok ( although not a sign that the battery would be dead)
=> Got to the conclusion that there was a short circuit somewhere.

After hours spent online I came across this video ( shout out to Timm ) :

Here I saw that the boot area can easily get water inside and as I had no other good option I tried drying the boot

1. I managed to get a "slim" friend to get her head and arm through the ski hatch and disconnected the terminals off the battery. Proof:
1766997385162.png
Then she connected the jump cables to the terminals so I can extend the terminals to the outside of the car.

2. got a blow dryer inside the boot and I installed a moisture absorbent from Ceresit. Kept them there for about three hours ( constantly moving and checking on the blow dryer )

1766997686941.png

3. After that I connected a jump starter to the cables ( that were connected to the terminals inside the boot ) AND THERE WERE LIGHTS!!!

4. Managed to open the boot, I installed the terminals on the battery again and the car started without skipping a beat....So the battery was OK.

5. Put the boot in the service position and started doing what TIMM shows in the video. The previous owner told me that he changed the rear right taillight and there it was. Water...and a lot of it!
1766997897953.png
1766998004024.pngthere were clear signs that water was getting through the wronly installed tail light. It got around the gasket that was not installed right.

took the lamp out, cleaned everything and installed it right ( with the gasket pulled all the way ) and did a water test and no water was getting around it but found another place where the water was getting in that area. I attached a video:


I will get it in a service to get all the lining and the fender removed to add/replace all the gakets and missing parts.

But here is the "fun" discovery. There are 3 computers in that corner ( at least on my car ) - The handbrake computer, one that deals with the PDC Parking sensors and one that manages the boot and the roof system. They were all sitting in a pool of water.


thank you for your help and I hope this will help others. I will post updates as I go on with the repair.
 
RobbiZ4 said:
Don't see any reason to not connect both cars, except your whole car represents a short.
Click to expand...
Indeed, is possible. :unsure:

MihaiDumitrache said:
1. I managed to get a "slim" friend to get her head and arm through the ski hatch and disconnected the terminals off the battery. Proof:
View attachment 288645
Then she connected the jump cables to the terminals so I can extend the terminals to the outside of the car.
Click to expand...
The terminals under the hood were sufficient in that situation.

MihaiDumitrache said:
1766998004024-png.288648


took the lamp out, cleaned everything and installed it right ( with the gasket pulled all the way ) and did a water test
Click to expand...
Did you seal the 3rd hole in the body, that typically stays open for water if new backlights get installed?

⌛ E89: Collection of the 9 typical age-related defects in the roof environment
 
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MihaiDumitrache said:
Well... I managed to get it running. I found an electrical scheme posted on the forum and figured out that:
a. If the jump starter didn't drain while connected to the terminals under the hood
b. The voltage on the battery was ok ( although not a sign that the battery would be dead)
=> Got to the conclusion that there was a short circuit somewhere.

After hours spent online I came across this video ( shout out to Timm ) :

Here I saw that the boot area can easily get water inside and as I had no other good option I tried drying the boot

1. I managed to get a "slim" friend to get her head and arm through the ski hatch and disconnected the terminals off the battery. Proof:
View attachment 288645
Then she connected the jump cables to the terminals so I can extend the terminals to the outside of the car.

2. got a blow dryer inside the boot and I installed a moisture absorbent from Ceresit. Kept them there for about three hours ( constantly moving and checking on the blow dryer )

View attachment 288646

3. After that I connected a jump starter to the cables ( that were connected to the terminals inside the boot ) AND THERE WERE LIGHTS!!!

4. Managed to open the boot, I installed the terminals on the battery again and the car started without skipping a beat....So the battery was OK.

5. Put the boot in the service position and started doing what TIMM shows in the video. The previous owner told me that he changed the rear right taillight and there it was. Water...and a lot of it!
View attachment 288647
View attachment 288648there were clear signs that water was getting through the wronly installed tail light. It got around the gasket that was not installed right.

took the lamp out, cleaned everything and installed it right ( with the gasket pulled all the way ) and did a water test and no water was getting around it but found another place where the water was getting in that area. I attached a video:


I will get it in a service to get all the lining and the fender removed to add/replace all the gakets and missing parts.

But here is the "fun" discovery. There are 3 computers in that corner ( at least on my car ) - The handbrake computer, one that deals with the PDC Parking sensors and one that manages the boot and the roof system. They were all sitting in a pool of water.


thank you for your help and I hope this will help others. I will post updates as I go on with the repair.
Click to expand...

Interesting…where do you hypothesise the short circuit to have been?
 
Hello. The car didn't seem to make any trouble. I kept checking if the battery drains overnight ( i lended a battery testing device from a friend ) and everything seems fine.
The error that kept showing up was for the parking break... And if i touched/moved the parking break module in the trunk ( previously dipping in a pool of water as you previously saw ) the error went away.
I thought it was a bad connection and decided to remove the connector and clean the pins.

The connector and the module were coroded, as you can see in the images below and the module had water inside.
1767539207800.png
1767539223569.png
1767539265740.png
The only problem now is that one pin was broken and is inside the connector. I will attach a picture with the module and you can see the place where the pin should be and one with the connector ( where you can see the tip of the pin )
1767539449099.png1767539473835.png

I dont know if this was causing the problems with the battery but now I have to find a way to release the parking break in order to get the car to BMW.
Do you know if there is an "analog" way to release the parking break?

Thnak you!
 
MihaiDumitrache said:
Do you know if there is an "analog" way to release the parking break?
Click to expand...
There isn't, a working EMF is required. Alternatively the 2 handbrake motors have to be driven manually from below the car.

Generally Pin 2 will be cut off due to electrochemical corrosion. Unfortunately this is the power supply of the module, which sits at the lowest position of this big black connector and so is the first affected by raising water in the trunk.

The missing pin can't be restored in a simple way due to the technology used when producing this module.

I've developed a solution to place a new power supply onto this mainboard, that you already have cut open.

Clean your connectors carefully and forget pin2, it can stay in the housing.
1767544943084.png
In total there are 3 power supply lines: 2x 50A for both motors on the right, pin 2 just for the electronics on the left. To reanimate the pcb, I've drilled 2 holes for the wires throught the EMF housing, routed one of the 50A contacts through an external 5A fuse back to pin 2 on the pcb. Works fine and is safe.

1767542987531.png
The external fuse has to be placed exact on this side of the module!

1767542993800.png
 
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RobbiZ4 said:
There isn't, a working EMF is required. Alternatively the 2 handbrake motors have to be driven manually from below the car.

Generally Pin 2 will be cut off due to electrochemical corrosion. Unfortunately this is the power supply of the module, which sits at the lowest position of this big black connector and so is the first affected by raising water in the trunk.

The missing pin can't be restored in a simple way due to the technology used when producing this module.

I've developed a solution to place a new power supply onto this mainboard, that you already have cut open.

Clean your connectors carefully and forget pin2, it can stay in the housing.

In total there are 3 power supply lines: 2x 50A for both motors on the right, pin 2 just for the electronics on the left. To reanimate the pcb, I've drilled 2 tiny holes throught the EMF housing, routed one of the 50A contacts through an external 5A fuse back to pin 2 on the pcb. Works fine and is safe.

View attachment 288944

View attachment 288945
Click to expand...
wow, thats great!
I didn't know that the part + connector and labour would get to 1k...its absurd. I found second hand parts for around 300-400 pounds.

But I will definitely give this a try....atleast I can unlock the breaks with this... I will get back to you!
 
@RobbiZ4 - would a code reader with the ability to wind back the rear brakes for pad swaps etc be able to release the handbrake, or does that go through that damaged module?
 
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