Anyone know if there is a way to check the amplifier to see if it is working . Just had it changed about 5 months ago and the same things are happening again. The car will not lock or unlock all the time and today the seatbelt extender did not come out to access the seat belt. Sure could use some help , thanks. 2004 CLK 500

 

You Should be in the CLK 500 forum not the W204

 

I'm sure the mods will catch this and then you may get people who know what you're dealing with!