PMGRANDS

I recently bought a 99 CLK320. I've read that the car comes with a 722.6xx transmission. I replaced the Tranny gasket and filter. Also put in new fluid.. Long story short, I took it for a ride and it won't shift to 2nd. It goes into reverse and 1st no problem but will not shift to 2nd.

I've read that it could be one of the following.. TCM, ECU, Speed Sensor Control, Gear Shifter & Module, Valve Body, Throttle Position Sensor, or the Conductor Plate, O-Rings on the Conductor Plate Connector. Is there anything else I'm missing?

Plutoe

What I find amazing is that you never mentioned a pre purchase test drive and or the presence of a check engine light----in any event and to eliminate all the HS get a transmission scan then you will know what to focus on!!

insame1

How did you check the fluid level?

Serndipity

Mechanically the 722.6xx quite bullet proof, with the vast majority of limp mode issues being due to the electrical modules (e.g. conductor plate, transmission control module, transmission sift module, speed sensor etc.).

As Plutoe suggested, diagnosis requires that you need to have your car scanned for fault codes, with the MB STAR diagnostic system.

I believe you'll find the link below, which starts with Part 1 of of a 6 part series regarding shifting problems, informative.

Note that even after proper diagnosis and parts replacement, you will need the MB STAR diagnostic system to clear any stored trouble codes (e.g. discussed in Part 4).