**CAR THREAD** battery drain??? Video included

[Clutchy]

Apologies about the car thread, delete if appropriate.

2014 M235i with 39k miles

Bought the car last week privately, battery was flat when I woke up this morning had to get AA to get me started.

Car tested and was found to be charging fine and the battery (AGM) in good condition just needed a full charge.

Discharge draw was 0.15 amps

However since owing the car it never wants to go into stop start despite all the other requirement (engine temp etc met) which could only leave insufficient charge being the reason it won't go into stop start in eco mode or any other mode.

Now I bought a decent trickle charger went to put it on and an hour after the car had last been turned off I could hear water being pumped around the engine (not leaking) sounds like the water pump was engaged as shown in the video.

I also opened the water resoviour to see water being squirted in at high pressure.

This must be causing a massive drain when the car is off, however it wasn't doing this when tested this morning

Any suggestions?


Link here https://youtu.be/4olO-xw5nfU
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Malaguti F12 Phantom-Dead, Suzuki AY50- Dead, NRG power DD LQ, CBR125.
*33 BHP restriction up on 10/12/14* Current bikes/car: SV 650 S/ MKIV GOLF
Guide to pass your test with no lessons!

[Copycat73]

[Clutchy]

In fairness, if there tests couldn't find the fault today I don't see how they would of when it was purchased.

It had been checked over in full by bmw 2 months ago with a video presentation.

Sliver lining, an excuse to get back on the bike
____________________
Malaguti F12 Phantom-Dead, Suzuki AY50- Dead, NRG power DD LQ, CBR125.
*33 BHP restriction up on 10/12/14* Current bikes/car: SV 650 S/ MKIV GOLF
Guide to pass your test with no lessons!

[Copycat73]

ok..

only sensible thing i have to say is .. Air Conditioning .. try pullin the fuse out.. see if that stops it...

and or turn the heater switch to warm .. even though the key is out of the ignition.

i think you have a "clever.". keep the car cool circuit when its parked up ..

and while your on read this ...
https://www.aircon-servicing.sg/why-aircon-auto-turn-on-and-off-by-itself/
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Whatever I post I have no citation and no intention of providing one..
caveat emptor

[RhynoCZ]

REST (Residual engine heat utilisation)

Check the REST is not running. REST uses the residual heat of the engine coolant to heat the cabin after you turn the engine off. It has its own auxiliary pump in the cooling system pushing the hot coolant through the heater core in the cabin (you can hear water running around) + turns on the cabin air ventilator = warm air comes out of the vents even when the engine is not running.

The REST system turns itself off (or should), when the coolant temperature drops below certain temperature and/or the battery voltage drops below 12.14V or so. Meaning, it should not be running with the engine cold and/or flat battery. This was and still is a pretty common feature in all the BMW and Mercedes-Benz cars from the 90's until today. You may activate the system with a button or program this function to happen automatically.

EDIT: I guess modern cars might not have a dedicated REST buton, but they still might have such option in the car's computer menu.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[bugeye_bob]

Test battery with multi meter, no load, then with ignition on but not running, and again with engine running and heated rear window on,
not sure how it was tested previous,

If the car has a tracker, or the car alarm has battery back up, these can draw extra current, but 0.15A is nothing.

a quick google about iffy Start and stop, and battery voltage is top of the list.

[Ste]

How much did you pay?

[Clutchy]

[Ste]

No particular reason, just seeing if you'd paid massively under the standard price but hadn't left any coins in the piggy bank for fixing whatever reasons there might be for its cheapness.

BCF always delivers so you shouldn't be surprised that BCF has been more helpful than the biggest UK car forum has been.

[Clutchy]

Just incase anyone was interested:

As expected the electric water pump is at fault and seems to want to turn itself on when it wants at night and draws and massive 30 amps.

Battery 'had' to be changed also as it had apparently damaged it due to running it nothing on more than 1 occasion.

So;

Electric water pump
New battery installed and registered /coded to the car
Labour and dignostics

Total arse-raping amount:
£1345.26


BMW customer services and managing director have been emailed
____________________
Malaguti F12 Phantom-Dead, Suzuki AY50- Dead, NRG power DD LQ, CBR125.
*33 BHP restriction up on 10/12/14* Current bikes/car: SV 650 S/ MKIV GOLF
Guide to pass your test with no lessons!

[-]

[UncleFester]

If you fit a new battery, the ECU needs to be told as the alternator charging output is monitored vs battery condition. You run the risk of damage to either battery and / or alternator if you don't do this.

Welcome to the world of BMW fredtronics.
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Module 1 and 2 passed - October 2014. Happy owner of a 2017 Z1000SX, ex owner of a YBR125 / CB500 / VFR800.

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[RhynoCZ]