E220 Cab (A124) Parasitic drain

[CRJ]

I have a late (1996) E220 cabriolet.
I had been experiencing a flat battery for the last couple of months which I put down to a 5 year old battery so I replaced it with a new one.
It was almost completely flatterned after 7 days of no use and returning from a 150 mile round trip.
In testing with a meter I am getting an 80ma "draw" with everything off.
Tried pulling each fuse one by one and and got a negligble drop (probably the radio anti-theft light).
Is this "normal" for my vehicle ?

 

[Tony Dyson]

The Maths aren't quite right, assuming you have a relatively healthy c80 AH battery? a current draw of 80mA should certainly take the edge off after 7 days but not drain your battery completely until around 40 Days. I can't remember where I read it but IIRC the sleeping drain should be around 30-35mA and not 80mA, the excess indicating a fault it would not be surprising that this fault will fluctuate as external forces adversely effect it, did you find the source of the 80mA drain in your earlier tests?

 

[Craiglxviii]

True. I had a 1.5A drain that killed my battery within the course of a day, what I didn’t know was that the alternator was also packing up so double whammy.

OP, try looking at the voltage regulator as first culprit...