Alan,
Just change the OVP and get it over with! It's cheap, easy and likely a culprit. Even if it isn't, it's good preventative maintenance!

Mbztrio,
I don't think your car has one... The OVP is Overvolt Protection Relay, it protects the cars electrical system from getting fried, but can go faulty after a few years and cause all sorts of electrical problem. If you want to learn more, do a search, this topic has been discussed a MILLION times!

Good luck Alon and just change it.

__________________
2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)