Help - Major electric drain

[bertiejaffa]

Hi all,

As you will know I have recently bought a Z4MC which I am thoroughly enjoying, however I have noticed that there is a large power drain somewhere when the car is parked up. I have checked for the usual things that I can think of such as ensuring the courtesy lights are off when the boot is closed and making sure that there are no auxillaries plugged into the cig lighter etc.

Any ideas what this could be? Has anyone experienced similar?

I did wonder if there is a way to disable to alarm/immobiliser using a particular set of key presses when locking the car?

Open to any suggestions as it is currently losing around 1v per day!!

I have checked the battery and it is fine and I have put my spare one on and that has the same issue - the alternator seems good - charging at 14v when the engine is running.

 

[enuff_zed]

One quick check you can do is look at the fuse box. If there are any piggyback fuses in there, or signs that someone has wired something extra in then that's a starting point.

 

[SonnyA85]

AA solar charger any good?

 

[bertiejaffa]

AA solar charger any good?

I do have a solar charger - didnt think to use that but will put it in. However it doesnt resolve the issue which is that after 7 days since I fitted a perfectly good battery with circa 12.7v on it the car is dead and the battery now only reads 2.3v

 

[ronk]

Try disconnecting the alternator and see if it still draws current while everything is . I experienced this fault on a car a few years ago. It was pulling about 4amps as I remember. An alternator repair fixed it of course.
Needless to say don’t run it in this condition

 

[SonnyA85]

AA solar charger any good?

I do have a solar charger - didnt think to use that but will put it in. However it doesnt resolve the issue which is that after 7 days since I fitted a perfectly good battery with circa 12.7v on it the car is dead and the battery now only reads 2.3v

Yeah sorry can't help on the drain front but thought a solar charger could offset it some what until you figure it out.

It literally could be anything in the car causing it.

 

[ronk]

Have you disconnected the alternator yet?

My car exhibited the same symptoms you described and the
Alternator was they culprit.

 

[Chippie]

One possible option, if the fuse box is easily acceptable, is to note the position’s of all the fuses and then remove them all and see if you still get the battery drain, if not then replace half and check again, gradually removing and replacing banks of fuse’s until you find the battery drain, it will probably throw loads of fault codes but at least you can hopefully trace the fault.

 

[bertiejaffa]

Thanks all for the advise - I need to check the alternator as suggested, I have watched a video showing how to check it but that had the alternator fully accessabile.

Silly question, rather than try to get my hand in the engine bay and disconnect the lead at the alternator end, can you please advise if it is as simple as disconnecting it at the battery end? Maybe the connection circled?

 

[horseless_carriage]

Disconnecting the battery lead will solve the problem, but I would advise disconnecting the negative lead (brown wire) instead. Disconnecting the negative lead first is generally considered a safer practice.

Also be very careful not to let any metal tools touch the positive leads when disconnecting, it will cause substantial arching and likely damage the battery.

 

[ronk]

From my experience having suffered the same draining problems, the disconnect at the alternator was the way to go - it took that one suspect component out of the loop without any doubt.

 

[Scooba_Steve]

the alternator fully accessabile.

All you have to do is take out the intake filter box. Screwdriver on the intake hose clamp, wiggle it out then one bolt on the alternator connection.

Would probably have been quicker than posting a photo of the boot :roll:

 

[Billbob10]

hi ,it might seem obvious but have you checked glove box boot light etc i had same problem and found the light in centre console was staying on. I only noticed it by accident when i we nt in my garage in the dark!!

 

[ronk]

I would suggest you accurately measure the current flow and not just the voltage drop. This will allow you a better indication of what is using current,