be careful...
the s class has two sensors for the throttle - if its the same system as mine...
one is on the pedal itself, the other is on the end of the cable. if the two get out of 'sync' - for example by a mechanic twisting the throttle cable end instead of the pedal - it can go into limp home mode - i.e. no throttle...
but apart from that - i have no idea! sorry