Monday, June 15, 2020

Technical Service Bulletin # Mercedes Benz Truck GL 550 LI27-50_P-0497102 Date: 120703

Technical Service Bulletin # Mercedes Benz Truck GL 550 LI27-50_P-0497102 Date: 120703

A/T - Switches To Limp Home Mode And One Or More DTC's Stored

Automatic transmission limp-home mode, fault codes 0717, 0718,

0722, 0723, 2200, 2201, 2204, 2205, 2206, 2207, 2767, 2768

Numero de tema: L127 5rnF-049710

Version: 2

Grupo de construccion: 27.50 Gear assembly

Edicion: 0703-2012

Validez: Automatic transmission 722.9 it is not possible to repair the EHS (VGS) in AMG vehicles

Motivo de modificacion: Note added: It is not possible to repair the EHS (VCS) in AMG vehicles

Reclamacion:

Automatic transmission 722.9 switches to limp-home while driving (gearshifts no longer possible) and/or one or more of the following fault codes

are stored or current:

2011 Mercedes Benz Truck GL 550 (164.886) V8-5.5L (273.963) Page 54

For vehicles with VGS1

2200 2201 2204 2205 2206 2207

For vehicles with VGS2 or VGS3

0717, 0718, 0722, 0723, 2767, 2768

Causa:

Rpm sensor fault

Remedio:

Process the speed sensor fault codes completely using the DAS/Xentry guided test (possible as of DVD 01/2011 and add-on 1740). This may or may

not entail a replacement of the EHS.

In the case of hardware replacement (when SDS instructs to do so, see attachment) the adaptation data of the old transmission control unit is read out

in the DAS/Xentry guided test and transferred to the new control unit after the repair. Subsequently, the transmission control unit, which is bolted

onto the electrohydraulic controller unit (EHS), may only be replaced using the EHS repair kit (A000 270 17 00) In other cases SDS will provide

alternate instructions

See also the Akubis direct film: "Replacement of "fully integrated transmission control" (VGS) controller unit at electrohydraulic controller unit

(EHS) on automatic transmission 722.9"

The VGS Control Unit (Control Module) only is to be replaced for VGS2 and VGS3 Control Unit versions with these fault codes, when SDS

instructs to do so VGS Control Unit is available as EHS Repair Kit (A000 270 17 00) Complete valve body "Electrohydraulic Controller Unit

(EHS)" replacement is necessary for VCS1 Control Unit versions when SDS instructs to do so. Control Unit Version is identified from the

Transmission Control Unit Log.

2011 Mercedes Benz Truck GL 550 (164.886) V8-5.5L (273.963) Page 55

Note in Cases where hardware replacement is specified:

This procedure differs from a complete valve body replacement as the adaptation data, coding and valve body calibration data are transferred from

the old VGS Control Unit to the new VGS control unit This data from the old VGS Control Unit is stored in the Star Diagnosis unit by processing

one of the above codes. The same Star Diagnosis SW stem unit MUST be used to process the fault code and perform initial startup of the new VGS

Control Unit. Failure to do so will result in the necessary data not being transferred and improper transmission functionality after VCS Control Unit

replacement.

1. Process the speed sensor fault code completely by following the instructions in DAS/Xentry related to the fault code Note: During the

replacement of the VGS Control Unit it is imperative that the position of the solenoid valves are noted and re-installed in their original positions

Failure to do so will cause a mismatch in the calibration data to respective solenoid valve(s) and subsequent shifting complaints.

2. Replace the VGS Control Unit per WIS instructions For the initial road test following VGS Control Unit replacement the vehicle must be driven

gently for the first several shifts in each gear since it will be necessary to bleed the air from the valve body. Until the air is bleed out irregular

shifting will be noticed momentarily and will clear up with subsequent shift processes. Because the adaptation data is transferred from the

original VGS Control Unit performing subsequent shift adaptations is not necessary.