Re: Car not shifting past 5,500 rpms!
This is exactly what has been discussed at length before.
You need to spin the front wheels, if they are stationary the PCM will lock down the rev's well before redline.
The other method is to get your hands on the Mercedes Star computer and software and put the car into "dyno mode"
Pulling fuses, resetting things, or anything short of turning the front tires or using the software will do nothing but set codes.