Tech Tip: Mercedes-Benz A/T Fluid Leaks at the Electrical Connector – UnderhoodService

Tech Tip: Mercedes-Benz A/T Fluid Leaks at the Electrical Connector

A 2002 ML 500 with a 722.6 automatic transmission may leak oil in the area of the electric connection. Secondary concerns may be oil in the wiring harness. Perform the following procedure to resolve the problem. Clean the transmission in the affected area and replace the electrical connector and the related O-rings ....

A 2002 ML 500 with a 722.6 automatic transmission may leak oil in the area of the electric connection. Secondary concerns may be oil in the wiring harness. Perform the following procedure to resolve the problem.

Service Procedure:
1. Clean the transmission in the affected area and replace the electrical connector and the related O-rings.

Note: The electrical connector may only be assembled/disassembled when transmission oil temperatures are less than 50° C in order to prevent damage to the conductor plate.

2. If there is transmission oil in the wiring loom, wipe it dry and blow out the plug at the transmission and ECU connections. The contacts can be cleaned with commercially available contact cleaner.

Note: When connecting the wiring harness to the transmission, ensure that the harness is routed in a tension-free path (see Fig. 1) and that no tension is applied to the electrical connector from the harness (see Fig. 2).

Courtesy of ALLDATA.

For information on products offered by ALLDATA, visit www.alldata.com.

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