| Diagnosis and Testing NOTE:Do not take short cuts or assume that critical adjustments have already been made. NOTE:Follow the procedure as written to avoid missing critical components or steps. To properly diagnose a concern have the following publications available: - OASIS massages
- Technical Service Bulletins (TSBs)
- Wiring Diagram
Preliminary Inspection and Diagnosis NOTE:When the faults are stored, the Automatic transmission module differentiates between continuous and sporadic faults. If a fault only occurs once within several driving cycles, it is stored as a sporadic fault. If the fault is not detected again over a distance of approximately 1000 km (625 miles) or 20 hours, it is cleared from the memory. If the fault is present again within the driving cycles, it is stored in the Automatic transmission module as a continuous fault and can be read out through the data link connector (DLC) with the scan tool. NOTE:After certain repairs to the transmisson and engine, it is necessary to clear the learned (adaptive) values from the Automatic transmission module and reconfigure the basic values with the scan tool, e. g. after changing the valve body assembly or the PCM. Proceed according to the following diagnosis flow chart. - Know and understand the customer's concern.
- Verify the concern by operating the vehicle.
- Check fluid level and condition.
- The Automatic transmission module, the signals of the sensors and the control of the actuators are monitored during the self-test. If faults occur, substitute functions are made available. The faults can be read out from the keep-alive memory of the Automatic transmission module with the scan tool. Thus, the faults are retained even if the battery or the Automatic transmission module plug are disconnected.
- Check whether any additional accessories have been installed after the vehicle was sold (and whether they have been installed correctly), for instance air conditioning, car telephone, cruise control system, trip computer, additional stop lamp.
- Check shift linkages for proper adjustment.
- Check TSBs and OASIS messages for the concern.
- Interrogate the trouble codes both in a test with the engine running (KOER) and in an engine-OFF test (KOEO). Note the displayed trouble codes.
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Emergency mode If critical faults (such as open or short circuit, electrical or hydraulic components defective) occur when driving, the transmission will continue to operate in an emergency running mode. If the fault occurs in "D", "3" or "2", then 3rd gear emergency mode is activated. If the fault occurs in "1", "P", "N" or "R" then the emergency running mode for that stage is activated. If the engine is started again in the emergency running mode and the fault occurs when selector lever is in position "D", "3" or "2" then 3rd gear is activated hydraulically, until the fault is rectified. | 
