2006 WK Overland
Your transmission is different than the ones indicated in this thread. Yours is a 545RFE and the subject of this thread is dealing with the Mercedes NAG1 transmission. Also, there is no "magic" switch to get yours out of limp home mode. You say that you've done everything? What is everything? How many miles are on the vehicle/transmission? When is the last time the transmission was serviced? Have you checked the fluid level when fully warmed up and its condition/color/smell? Have you checked for Diagnostic Trouble Codes (DTC) using an advanced diagnostic scanner that can read transmission codes?