Battery problems

Andrew Sheldon · Post by **Andrew Sheldon** » Sat Jun 25, 2022 9:23 am

I have a 2006 E85 2.0 litre Z4. I had to leave my car for 7months in France, with a bit of a struggle she is now back in the UK. There have been one or two little issues as a result of being left that long a period of time. My main issue being a dead battery which was a shame because she had the original 16 year old battery that was working fine up until the time I left her.
I replaced the battery with a new Bosch and have noticed there is a constant parasitic drain of around 1.1 amps taking place. This happens with the car locked or unlocked. I have removed the boot light and the interior centre console light (that wasn't switching off btw) and there is still the same drain.
Over a two to three day period this depletes my new battery to almost half of its power.
My question is, are there any common problems regarding systems on the Z4 that fail and may be the cause this parasitic drain. The only thing I can think to do is to pull out the fuses one by one until I find the right one. Not sure how this would work with relays and if you can do the same sort of tests. I have checked all the obvious things that may have been the cause but haven't come across anything.
I am currently having to disconnect the battery at the end of the day which is not an ideal situation.
Advice/help badly needed

SonnyA85 · Post by **SonnyA85** » Sat Jun 25, 2022 9:51 am

Battery drain could literally be anything and will take a lot of time and investigation to find.

In the mean time get yourself a decent smart charger and charge the battery to full and leave it on trickle charge rather than disconnecting.

Apparently the cd changer can become a drain as it tried to constantly do something.

buzyg · Post by **buzyg** » Sat Jun 25, 2022 9:55 am

Working your way through the fuses will hopefully find it. I had a battery drain issue that, I was told, was caused by the petrol flap not closing properly. It's gone anyway. Trackers also draw power if fitted.

grannyknot · Post by **grannyknot** » Sat Jun 25, 2022 11:21 am

You could also eliminate the glove box and cubby storage behind the seats as a culprit by setting your phone to video camera and putting it inside to see if they are illuminated when closed up.

Andrew Sheldon · Post by **Andrew Sheldon** » Sat Jun 25, 2022 1:08 pm

SonnyA85 wrote: ↑Sat Jun 25, 2022 9:51 am Battery drain could literally be anything and will take a lot of time and investigation to find.

In the mean time get yourself a decent smart charger and charge the battery to full and leave it on trickle charge rather than disconnecting.

Apparently the cd changer can become a drain as it tried to constantly do something.

I havent got a cd changer but leaving smart charger on isnt such a bad idea, at least I wont have to keep resetting the clock. Thnks for help.

Andrew Sheldon · Post by **Andrew Sheldon** » Sat Jun 25, 2022 1:15 pm

buzyg wrote: ↑Sat Jun 25, 2022 9:55 am Working your way through the fuses will hopefully find it. I had a battery drain issue that, I was told, was caused by the petrol flap not closing properly. It's gone anyway. Trackers also draw power if fitted.

I started to remove the fuses but quickly realised it would take me hours and wondered if I might do more harm than good. The petrol flap plunger is one thing that I too considered, however I still had a power drain whether the car was locked or not and the petrol cap lock plunger seemed to be working as it should. I will pull that fuse however and double check it.

Andrew Sheldon · Post by **Andrew Sheldon** » Sat Jun 25, 2022 1:24 pm

grannyknot wrote: ↑Sat Jun 25, 2022 11:21 am You could also eliminate the glove box and cubby storage behind the seats as a culprit by setting your phone to video camera and putting it inside to see if they are illuminated when closed up.

I like your cunning thinking, but yeah I have taken out the light for the cubbyhole and boot, the glove box light doesnt appear to be in place, there is a hole but no fitting and could see no light on around that area. Thnks for your help

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