Dead Battery 0.87 amp draw"MB ML320 CDI"

**electrones** · 28th January, 2015, 02:32 PM

Hi friends

MB ML320 W164 drain battery at 0.87A with car all closed, hooked up amp meter and i found a fluctuating draw 0.92/0.87A (digital gauge). Carefully i removed fuse all from rigth rear compartment and on engine compartment to see if amp meter but without success.
I need take out relay too?!?
Any defect module on this car???
What can be the problem, some one have passed for this problem before!!!
Suggestions please!!

**bursuc** · 28th January, 2015, 03:32 PM

Quick question - The Alarm siren works ? What fault codes do you have on rear SAM unit ? somehing regarding alarm horn ?
If yes , that means the battery inside alarm siren is bad- this is the current drain regarding the alarm sire.

How to test it : stay in the car - Lock the car - Wait between 30 seconds and 1 min - move inside the car so the ultrasonic sensors activate the siren - If the hazard lighhts start flashing but there is no alarm sound, there you go

Please report back what you fiind

best regards

**mercis** · 28th January, 2015, 05:11 PM

and check sam front and rear for water

**alessioblaupunkt** · 28th January, 2015, 06:27 PM

Is radio OEM or not?

**simaservis1108** · 28th January, 2015, 07:34 PM

Front and Rear SAM check for water ingress.
Listen if radio makes any noise(like it is loading a CD) when it is turned off.
Alarm siren,as someone suggested.
Check door microswitches.
Check from fan for water ingress also.
Check if car has ESL emulator,sometimes they can cause trouble.

**mercis** · 28th January, 2015, 08:09 PM

remove 12v from glow plug electronic

**rideon** · 28th January, 2015, 10:26 PM

Way OFF TOPIC.........
If this thread goes any further, electrones will end up with mercedes parts all over the place....

**bursuc** · 29th January, 2015, 04:23 PM

Originally Posted by rideon

Way OFF TOPIC.........
If this thread goes any further, electrones will end up with mercedes parts all over the place....

is not that bad , but ussually is a simple thing...they can't all of them go wrong . mot likely the current drainage between 0.70 A - 1.2 A - and fluctuating is because one of the sistem dosent switch off an is fluctuating because can bus network try to turn it off ... most likely looks like an alarm siren . From my experience

P.S. - I know most of you guys know how CAN Bus works ( i just put tis P.S because i don't want to offend someoane

)

**rideon** · 29th January, 2015, 06:19 PM

This is not about offending someone ,is about helping....
Think was an audi with a faulty amplifier,every now and then didn't go to sleep.....wasted 2 days on that......
and ended up with an "explode"view of the car...
Once found a flooded gps module lost under the floor trim (previous owner didn't bother to remove)
and the list could go on,

**deondti** · 29th January, 2015, 06:38 PM

On those cars , units that I found in the past not allowing the car to go into sleep mode...

Underneath the seat are the seat control modules

also

Cluster

Unplug a unit at a time,
reconnect amp meter ,
arm the alarm and wait patiently

**electrones** · 29th January, 2015, 10:18 PM

Hi friends

Thank you all for suggestions, tips and more but the problem was the AC compressor.
I found a feed line 30+ in red wire AC Compressor after take off the wire of bypass done by magician who does not know what to do when AC system has faults so far the battery does not drain.
I will test another day battery drain and verify what really happened because this deviation have a reason. ?

Cheers