That worked for my Check Engine light, it did clear the CE light and code.
But not with the SRS light. I had it unplugged all night! Still the stupid light came on. So you have to take it in.
My friend Justin with a 1999 E430: I unplugged his seatbelt and his SRS light went on, I then plugged it back in and it automatically sensed that it was OK and turned back off! THey must have updated the OBDII to correct that problem by 1999.
2006 E350 w/ 155k miles (Daily Driver)
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!)