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Emergency Program

When a malfunction occurs within the transmission, the emergency program (failsafe mode) will be initiated. The emergency program will prevent unintended gear engagement and ensure driver safety. The following will occur during failsafe operation:

The fault indicator varies depending upon model, year and cluster type etc. See Fig 1 . High version instrument cluster will display a message in the matrix display. Vehicles with low version clusters will display a fault symbol in the cluster. During failsafe mode the transmission will be shifted into a higher gear to allow the vehicle to be driven to a service location. Depending upon application, the transmission will shift into 3rd or 4th gear (on a 4 spd) and 4th or 5th gear (on a 5 spd). For example the A5S360R transmission will go into 5th gear when there is a malfunction and 4th when there is a power failure to the TCM. Since pressure regulation ceases, the shift to failsafe mode will be abrupt or harsh, unless the transmission is already in the failsafe gear. On newer OBD II complaint vehicles, the MIL light will also be illuminated by the ECM (DME).

Fig 1: E46 Transmission Fault Indicator
G00317086Courtesy of BMW OF NORTH AMERICA, INC.
NOTE: Note: When diagnosing transmission related complaints, it is possible to have an erroneous fault indicator warning. Faults in the cluster can cause a false indication or "Trans Program" message. One indication of this scenario would be a transmission fault message in the cluster with no transmission faults stored in the TCM.