Workshop Hints
Workshop HintsCentral Connector
To simplify access, a small central connector is located on the left side of the gearbox below the clutch sensor. The central connector incorporates the circuit connections for the following hydraulic unit components:
^ Wiring for hydraulic valves
^ Signal line for pressure sensor
^ Voltage and ground supply for pressure sensor
^ Ground connection for hydraulic valves
The gearshift lever accommodates a Micro-Quadlock system with a 12 pin tray. Two pins are additionally assigned in the US version. They are the outputs for the illuminated gearshift lever position indicator, which is located on the drivers side next to the gearshift lever on the center console.
SMG Bus System Overview
Diagnosis
Diagnosis corresponds to E46 diagnostics and contains the following:
^ Read identification
^ Read fault memory
^ Delete fault memory
^ Diagnosis request
Programming
The SMG Control Module is programmable. Programming must be performed whenever the SMG Control Module has been replaced.
Working on Hydraulic System
Note: Prior to any work on the hydraulic system, the system pressure must be reduced with the service function "Before working on hydraulic system" in the DlSplus/GT1.
^ The hydraulic pump relay must be removed to prevent the hydraulic pump from activating. The relay must not be reconnected for the entire duration of the repair work.
^ The service function After working on hydraulic system must be implemented with the DlSplus/GT1 (to vent the hydraulic system).
^ The service function Teach gearbox must be implemented with the DlSplus/GT1. The hydraulic pump must not run when dry,
^ After work is completed on the hydraulic system, the hydraulic fluid level must be checked and topped up if necessary. The hydraulic pump relay can be reinstalled. The hydraulic fluid level must be checked again.
Teaching Gearbox
The service function Teaching gearbox must be implemented with the DlSplus/GT1 when the following components are replaced:
^ SMG Control Module
^ SMG Transmission
^ Clutch
^ Clutch sensor
Note: The SMG control system learns the clutching characteristic during the drive off operation. There may be impaired comfort during the initial gearshift operations.