More service is always better than less.

It needs to be scanned by a high end scanner such as MB's SDS or a few others. A hand held OBDII scanner will read engine codes but not the trans module.

The adaptation values (how your trans has attempted to adjust itself recently) is also valuable data as is the tech's knowledge interperting that data. Sometimes the dealer is your best bet.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)