hook an ammeter inline with the negative cable and let the car sit and check your draw after sitting 30 minutes. 203 should be about 50mA or less.

__________________


1980 500SE/AMG Euro
1981 500SEL Euro
1982 380SEL
1983 300TD
1983 500SEC/AMG Euro
1984 500SEC
1984 300TD Euro
1986 190E 2.3-16
1986 190E 2.3
1987 300D
1997 C36 AMG
2003 C320T 4matic

past: 1969 280SE 4.5 | 1978 240D | 1978 300D | 1981 300SD | 1981 300SD | 1982 300CD | 1983 300CD | 1983 300SD | 1983 380SEC | 1984 300D | 1984 300D | 1984 300TD | 1984 500SEL | 1984 300SD | 1985 300D | 1986 300E | 1986 560SEL | 1986 560SEL/Carat | 1987 560SEC | 1991 300D 2.5 | 2006 R350

Thanks Ferdman.I tried it but still dont work.Today,my mechanic told me the car is using 0.8A (0.5A for normal car) without the engine starts.Something is draining the battery.

That is way way to much amperage draw. A 2001+ C class should draw
between 20 and 50 milliamps with the car locked after 45 minutes.
your car is drawing 800 ma. Front power seats, GPS Comand units, Phone
PSE control units and Rear Sam control modules are all common draw issues
on that car. You will need to isolate the circut with the draw.
The Prefuse box next to the battery is a good place. You can remove power
from all the main power sam/fuseboxes on the car whilst watching the draw
one at a time.
Once you disconnect the fuse box with the draw, start chasing circuts one by
one by pulling fuses and disconnecing ecus.

Good luck and remember, it takes some ecus over an hour to got to sleep and stop drawing current. (E-call and GPS)

Euro cars with stationary heaters can have draws from the heater controller
as well.

Regards,
DR.D

__________________
Dr.Diesel -
Shop Foreman
Master Guild Mercedes-Benz Technician.

Think the dealer is expensive? Do you know how much it costs to train a dealer tech? Or buy the required MB special tools to have on hand?