Automatic Transmission
Inspection and Verification
This section is intended to provide a means for the technician to diagnose transmission component faults, rather than replacing the entire unit.
However, there are a number of situations where the replacement of the unit is the only practical solution, and this section will cover the diagnosis necessary to gather the information required for transmission replacement to be authorized by the warranty prior approval program (WPAP) where it applies, as well as covering the diagnostic trouble codes (DTCs) stored by the control module.
The basic checks of the transmission (fluid condition and level, etc) should be carried out first, and this will mean using the approved diagnostic system or other equipment with data logging facility to monitor temperatures, etc.
For information on the operation of the transmission, refer to the relevant this product section.
1 Verify the customer concern.
2 Visually inspect for obvious signs of mechanical or electrical damage.
3 If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4 Use the approved diagnostic system or a scan tool to retrieve any DTCs before moving onto the DTC index.
- Because the DTCs are stored in more than one module, a complete vehicle read is recommended
- Make sure that all DTCs are cleared following rectification.
DTC Index
For a list of Diagnostic Trouble Codes (DTCs) that could be logged on this vehicle, please refer to A L L Diagnostic Trouble Codes ( DTC ). For additional information, refer to Diagnostic Trouble Code (DTC) Index - DTC: Transmission Control Module (TCM) - Bosch Transmission Control Module (TCM) - Bosch