E85 LONG RUNNING BATTERY DRAIN - NEED HELP IN FINDING A COMPANY WHO CAN IDENTIFY PROBLEM

[longleydel]

If you find it's draining really fast within a week and drops below 80% from full within a week and when the alarm isn't on full mode then I'd see if someone with a decent scanner can run a test for you.

I have a Carly if you are anywhere near Glasgow I'll be happy to check for issues I'm home most of the time anyways and I can even potentially test your battery using my smart charger and see what it says.

Hope you get it sorted. It could be the alternator if it's not the battery. It's not being charged when driven and you are just depleting the battery more by starting the car and using it.

So I'd Google how to test the alternator and search on here as well and YouTube. That could be the issue as well. Unless your mechanic already tested the alternator

Hi, thanks for your message. Its great that the Forum attracts many knowledgeable people willing to help and advise.

Thank you for your kind offer, unfortunately I live in the south east corner of England.

The alternator was tested by the auto electrician last summer and found to be working normally. My battery tester has the facilty to check the alternator and run a ripple test. I did this more recently and everything was normal.

Thanks again.

Derek

 

[Ewazix]

The FSU hedgehog your tech' suggested might be at fault is listed with the superceded part numbers on realoem.com, lots of aftermarket ones around for sale on the web when searching for the original part no.
https://www.realoem.com/bmw/enUS/partxref?q=64+11+6+920+365

 

[longleydel]

Many thanks for this.

Cheap enough to buy and swap it over, given earlier thoughts that the drain may relate to the blower/climate control unit. I believe a faulty hedgehog can still power up the the climate control even though ignition off/car locked etc.

Think I'll also invest in a multi-meter and test everything fuse by fuse. Online videos on identifying a parasitic drain appear really helpful.

Derek

 

[Mike6]

Electrical problems are way above my paygrade but going back to basics parasitic drain would presumably mean problems with a circuit that stays live when ignition is switched off. If that is correct then I would hope you could eliminate a number of the cars electrical circuits.
You say you have checked boot light, internal light but with car locked I am not sure how you can be sure bootlight, glovebox light and pull down locker light have all gone out. I would at least start be removing these bulbs as they are all known factors in battery drain.
If you can I would leave car unlocked when parked up at home to eliminate any possibility of drain from alarm, locking mechanism etc.
A further probably unhelpful suggestion is to check all connectors to battery (Goodness know what all those leads are for) and to the starter motor and earths.
Now gone way beyond my comfort zone but good luck in tracking down the problem.

 

[longleydel]

Thanks for your comments Mike.

Electrical issues don't come easily to me either, but, research on the internet, the Forum and online videos about tracing parasitic drains suggests its not too difficult, just time consuming.

In terms of checking fuses I was going to start with those that remain live once the car is locked (located a useful fuse box diagram on the Forum yesterday showing the cabin fuses).

I have removed the boot light bulb. Oddly, I don't have a glovebox light which is strange given the vehicle is a 3.0 SE (understand where you have a light people leave their phone in the glove box on video to check). I know the pull down locker light is going out as I can just see it doing so when I close the compartment.

The auto electrician seemed to rule out loose battery connectors (which I had already checked) and earths etc.

I think not locking/alarming etc is a good approach in the meantime.

Derek

 

[SonnyA85]

Definitely lock it buddy. But don't use the fob use the key in the door.

 

[longleydel]

Point taken, definitely.

 

[bg1]

Thanks SonnyA85 and Ewazix for your comments. I bought the car privately last July and have probably done about 1,100 since. I try to give the car a good run at (up to an hour) every week, but this hasn't always happened, especially during the winter. Iv'e bought 2 Bosch (680 CCA) batteries so far, the last around 6 weeks ago.

I use a Topdon BT100 battery tester to check battery health 3 or 4 times a week. When the battery shows low voltage/CCA , or to the point where the engine fails to turn over (usually 4-5 days) I use a NOCO Genius 5 (5 amp) smart charger to recharge it. I have avoided jump starting the second battery, as I believe this helped the first one to die.

An auto electrician carried out numerous tests last summer and concluded like you that the car wasn't being used sufficiently. I then used it more, but the drain still persisted. The same auto electrician carried out further testing more recently and thought we had identified the drain to either the climate control unit or the blower resistor (hedgehog). All relevant fuses were removed, but after 3 days the battery had flattened (down to around 8.5v). The battery has been recharged out of the car. I haven't put the battery back yet, but it has held a full charge now for several days. Presumably, the battery would loose its charge out of the car if it was no longer servicable.

Ewazix, you mention changing the hedgehog. Can you still purchase these new? I believe the original part no. for these is 64 11 6 920 365 (fits all models of E85/E86), but ( I read somewhere) was superceeded by part no. 64 11 5A 3F3B9. Unfortunately, I cannot track down any new ones on line with these part numbers. There are ones for for the E46 avaiable new, but unclear if the same blower was fitted to Z4's (like quite a few other parts from the E46).

Thanks again for your helpful comments.

Derek

Could I ask for a brief 'how to' use this Topdon. I don't really understand!?

 

[longleydel]

Hi, yes no problem. The model I have is the BT100. The user manual is really good. In use the tester is fairly intuitive and after a few uses should become second nature. You can also find some helpful videos on U-Tube.

I tend to use it more for keeping an eye on the battery performance (particularly in view of the intermittant parasitic battery drain I have). Always connect the positive clamp to the battery first and disconnect last. The unit powers up once the nagative clamp is attached to the battery (no internal batteries). The important thing is that as you go through the menu when carrying out the Battery Test is to identify the relevant CCA (Cold Cranking Ameprage) for your battery (should be a label on the battery). Mine is 680 CCA.

This battery test shows the health and charge held in the battery (e.g. a new battery would probably show around 100% and 98% respectively), the level of CCA (often shows more than stated on the battery, but seems this is quite normal), current voltage (a good battery is usually between 12 and 13 volts), and internal resistance measured in ohms (must admit i'm a little unclear about the relevance of this, though the higher the resistance, the less charge in the battery).

One thing I have noted with this test is that if the battery voltage is quite low (around 9.5 and less) the tester will tell you to replace the battery. But, this isn't always the case. I have recharged (using a trickle charger) a battery so indicated and it has been fine.

The tester also measures the CCA capability of the the battery - will tell you if this is functioning normally or not, and another test called a ripple test which I believe is to do with the charging side of things (again a normal, or otherwise reading,) and a separate charging test of the ability of the alternator to recharge the battery.

I hope this helps.

I looked around for some time for an affordable, but fairly good quality tester, before settling on this one from Amazon.

Derek

 

[SonnyA85]

If you buy a really good battery it will show a higher CCA than on the spec and a higher voltage too. My Bosch did so. I'm on my third battery in 6 years because of my low miles and if you let the battery go below a certain voltage I think 12v too many times it will just get worse and worse. You can get away with it a couple of times but the more drained it is and the longer it sits like that the worse it is.

It's why some folk have batteries last 10-15 years. They have them sitting around 90% full all year round.

 

[SonnyA85]

I just remembered sometimes you can have an intermittent fault with an alternator as in it works sometimes and other times it doesn't might be worth looking into or finding out a way to test it regularly.

 

[jimbo1958]

I had a Parasitic Drain on my old E85 that BMW traced to a faulty Gaptech Module. Don't know how they found it as it was located under the gearstick console.

 

[john-e89]

The drain on my M was the roof motor, still worked but I've taken it out, disconnected it, and that was the culprit.

 

[bertiejaffa]

My recent battery drain was the sat nav DVD that was randomly turning itself on when the car was locked.

 

[SonnyA85]

My recent battery drain was the sat nav DVD that was randomly turning itself on when the car was locked.

Interesting I have a cd changer but got rid of the OEM head unit years ago. I may need to disconnect the thing and eBay it

 

[longleydel]

Hi everyone, Iv'e been away since the early hours of Thursday morning and only just seen your comments. Many thanks for these. I 'll take a look at these areas and also chat with the auto electrician to try and track down the culprit.

Derek