help please with e300 problem
 

I just bought a 1996 e300 as a "project" and I may have made a MB newbe type error. I charged the battery using the JUMP START post under the hood. After I did that I now get a "check engine electronics" check engine error.
The car still starts and runs fine but the multi function system is telling me that just about everything is broken.

My question is what did I do and how do I fix it????

Connect a scanner to the OBD-II port and check for codes. You might also try disconnecting the battery.

It's most likely not catastrophic. Do as Matt suggests and connect into the ODB2 with a code scanner. You need to buy one anyway if you work on '96 and newer cars. This should allow you to clear the codes.

In the future, no matter what you are working on always take the time to properly charge the battery by connecting directly to the battery posts making sure the cables from the car are already removed completely.

Good Luck,

-GH

I would bet the OVP is blown,

It cannot be the OVP, as this car doesn't have one.