aamirkhan

First, My battery died b/c i left the lights on.
i charged the battery but then the ignition wouldnt switch or turn at all.
went and bought a brand new battery and the battery was good
for a couple of days (2-3) and then the brand new battery died.
any advice what this problem could be and why would it effect
the ignition from turning at all?

Chauss

Sounds like a bad ground.

lexlyf

Hmmm. Sounds like you may have a fried front and/or rear SAM module. With all of the electrical components in the MB, these modules (one physically in the front of the car & the other in the rear) assist in the proper powering on and off (w/ or w/o key or keyless go card, if applicable) of the various systems (i.e. radio, int lights, hvac, inst. cluster lighting, etc.).

These SAMs are a common weak point in the MB electrical system. They are often damaged/fried through voltage spikes and/or voltage irregularities. If you attempted to recharge your dead battery while still connected to your car, I can see a voltage spike/irregularity, due to the recharger, frying a SAM.

You could have also sent a spike through the system upon reinstalling another battery. As stated above, these SAMs are not as reliable as they should be.

The net effect of a fried SAM is that some of your electrical components are not powering down, thus excessively draining the battery. Just as your noticing, a brand new or fully charged battery only lasts 2/3 days tops.

I discovered all of this when trying to diagnose the same problem in my own CL600. My CL had just come back from the stealership upon addressing the cluster recall when I starting experiencing this problem. Hopefully, you have a warranty, preferably Starmark, and it will cost nothing for your local stealership to fix.

I would inform your SA to have both SAM modules checked. I recommend this b/c MB technicians have a difficult time correctly diagnosing SAM failure in a one visit attempt.