PLEEEASE HELP!!!!!!! Code P0700 on (W220)
Code 0700 corresponds to Transmission Control System Malfunction.
Its display in 722.X automatic transmissions is more a can of worms than a specific clue. The reasons, transmission maintenance could have been overlooked due to bad original schedule (ATF and Filter replacement might have not been required on User's Maintenance Guide); ATF might have been contaminated by coolant fluid due to Coolant System failure; Valve Tray Unit might have failing/damaged component; electronic failure (connector, cable, circuit component, TCU). Whatever it is may not only be a royal pain, but also quite expensive (Valve Tray, TCU). Make sure whoever is going to trouble-shoot this is very knowledgeable and reliably honest.
Good Luck,


If fluid wicked up from the electrical connector on the transmission it will cause shifting isssues and that code.
Less than 10 bucks for the upgraded o-ring and connector dry out the leaked fluid replace the connector and your problem should be resolved.
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Last edited by salmatari; Apr 1, 2011 at 12:25 PM.


There are several threads here on cleaning the TCM. A greatly simplified version:
Open the SAM (Signal Acquisition Module) under the hood at the base of the right (passenger) side of the windshield.
Find the wire harness with traces of ATF, follow it to the TCM.
Remove the TCM and carefully open it. Use brake cleaner to carefully and thoroughly clean the board.
Replace everything. Repeat if necessary after more ATF wicks into the TCM.
Start by looking at the sticky at the top of the page that says "start here". Look for your problem. Read, read, read. There are several similar threads shown under this answer. Read, read, read.
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