High Rate of Battery Discharge Error

[Pjwmhere]

Hi All,

I recently bought a 2013 x6 40d msport and a couple of days later I started getting a charging fault so took it to my local mechanic and they tested the alternator and said it was not good so charged me £440 for a new alternator. It then seemed ok but in the mornings it started coming up with a high rate of battery discharge error so I took it back to garage and the tested battery and charged me £350 to put a new AGM battery in but next day code came up again. I took it back and they said battery needed registered and did that free of charge however, next morning the error still came up.
I ordered an Ancel BMW scanner and ran it and it said the ECU did not recognise the IBS so took it back to garage yesterday and they have installed a new IBS but got home and original charging fault error has come back and ran the scanner and it still does not recognise the IBS. It’s cost me over a grand and still no further forward. I have checked to see if anything is draining it and nothing else seems to be on. Unplugged everything I could and I don’t have CAS doors. Anyone had anything similar. I picked up two other codes, one for EGR sensor and one for transfer case oil wear which I doubt will be connected. Driving me batshit crazy

[X5Sport]

Main Dealer or Indy?

Worth checking that all of the ground wires are fully tightened and clean. Also have a look at the jump start points under the bonnet. The +ve should be tight. Power goes from the alternator to that point and then back to the battery.

If you can, see if someone has a ‘current clamp’ as that will tell you what amperage is coming off the alternator. A check of the output voltage (no more than 14.8V, typically 14.4V) to see if that’s OK. Given all the hardware has been replaced, wiring would be worth looking at. Check the engine to body earthing straps too.

The following notes are in the BMW technical manual for the IBS: Installers have to be very careful with it or it can be destroyed.

IMG_3272.jpeg (211.32 KiB) Viewed 8403 times

[Pjwmhere]

Hi,

Thanks so much for your reply, it was an independent garage but the parts came from BMW. I will check the jump start points tomorrow but car is back in to have the transmission fluid replaced next week which he already told me won’t be cheap as the fluid is £29 a litre. I will ask them to check the other wiring then too. They said they registered the battery but on reading up it needs to be registered and coded so not sure if they have done that. I might have a look at that tomorrow as my scanner has that function. I’m already wishing I kept my E53 X5. Even with 230k on the clock it ran like a dream with none of this. In two years I did 40k miles and only had to replace the tyres and a wheel bearing

[X5Sport]

The Indy is right about the fluids. Ideally you want the whole lot changed from front to back. Note the 40d has a special rear diff with three separate chambers and two different fluids. They MUST be the correct ones. Main box uses ZF Lifeguard 8. A full change on mine was just over £1,000 a few years back. They MUST also replace the bottom of the auto box and use new bolts. The base is the filter assembly. Should be replaced every 50,000 miles or 8 years. They may have got the kit from ZF for the box anyway, and it has everything you need.

If you weren’t already aware, tyre choice is critical to the E70 & 71. Wrong choices break the transfer boxes and diffs.

Also worth bearing in mind is the N57 engine ought to have its oil and filter changed every 12 months regardless of whether that is low mileage. Do it to protect the timing chain. Don’t go with the BMW 2 year/20,000 mile intervals. I know do mine once a year even though I only did less than 1,500 miles last year.

[Leslie]

Was the engine running when the charging fault error occured ? as this fault can occur when doors are open too long etc as the current draw is quite high till it shuts down after 20 mins or so.

[Pjwmhere]

Good Morning,

Yes the doors were closed and engine was running when the charging fault occurred. I just went to start it this morning and the high rate of battery discharge error came on again. I checked the jump start terminals and they seem ok. This is the error showing when I run the battery scan.

[X5Sport]

Have they actually plugged it in? The IBS Sensor is the block on the -ve cable. It contains a CAN Bus device pcb and is static sensitive. Mishandle it and game over! Mishandling in this case means not wearing a static strap, dropping it, undoing the wrong nut or jump starting the car at the battery itself. The image below is the top of my E71 battery so you have something to compare with. I’ve marked the two relevant points with yellow circles. The connector must be plugged in at both ends.

IMG_1998.jpeg (170.14 KiB) Viewed 7883 times

and closer…the blue connector.

IMG_2001.jpeg (140.29 KiB) Viewed 7883 times

[Pjwmhere]

Ok, I checked and it all appears pretty much identical to yours. If I try coding the battery with my scanner, would the number in the second picture be required? Or would it be the number on the battery bar code?

[Leslie]

It's most likely an earth corrosion issue causing a high resistance and voltage drop , I've read on here about earth wires on the boot floor that were crumbling and corroded where a bunch of them join the floor I can't find the thread but that's what I'd be looking for next.
I've never coded a battery but I suspect you are looking to input the model Eg 019 would be the lead /acid type and the cold cranking amps or amp hour size.x5sport will know , I just try and fit like for like .

[X5Sport]

Recoding the battery needs no more than it’s type (AGM) and current rating - mine is set to AGM 90Ah. The battery is an AGM 95Ah but that option isn’t listed on my coding tool.

Interesting that the IBS unit is unprotected - as in bare - given it’s a sensitive component. Maybe BMW went cheaper later.

[Alan Gunn]

As above that IBS should have cover.
I think that is your problem it has had a bang as i don't think the cover comes off easily.
Maybe try a second hand IBS or if you know anybody with one you cod try just to test.

[Pjwmhere]

Hi thanks for your replies, I will have a look at the earthing points. I’m not sure what you mean by doesn’t have a cover. The whole battery was covered, I had to take it off to get the pictures. I can’t see how it could have taken a knock as there was nothing could get to it and it was just fitted the other day.

[X5Sport]

The IBS should have a fully protective cover as it does on mine. It’s the device on the -ve terminal. It needs protecting from mechanical impact as well as static discharge. Yours is ‘bare’.

[marti]

Had this problem, so I unplugged the IBS which also disables the stop/start which I like , havent had any problem with the battery or any electrical gremlins...unplugged over four years ago, yes still get the code if scanned, but I know what it is......

[Pjwmhere]

Still no further forward but I could do with some more advice. When I ran the scan on the car, one of the fault codes that came up was the tilt and motion sensor. Anyway, over the weekend I was sitting in the car with it locked and completely still trying to work out what could be draining the battery. Anyway, the car started beeping and would do so every so often. So my question is, would that cause the high battery drain and can you turn off the tilt sensor so I can see if it stops the message. It would at least tell me if that is the problem.