Emergency Running Function

In order to ensure a safe driving state and to prevent damage to the automatic transmission, the TCM control module switches to limp-home mode in the event of critical faults. A diagnostic trouble code (DTC) assigned to the fault is stored in memory. All solenoid and regulating valves are thus de-energized.

The net effect is:

• The last engaged gear remains engaged.
• The modulating pressure and shift pressures rise to the maximum levels.
• The torque converter lockup clutch is deactivated.

In order to preserve the operability of the vehicle to some extent, the hydraulic control can be used to engage 2nd gear or reverse using the following procedure:

• Stop the vehicle.
• Move selector lever to "P".
• Switch off engine.
• Wait at least 10 seconds.
• Start engine.
• Move selector lever to D: 2nd gear.
• Move selector lever to R: Reverse gear.

The limp-home function remains active until the DTC is rectified or the stored DTC is erased with the appropriate scan tool. Sporadic faults can be reset via ignition OFF/ON.