Shift Patterns: Upshifts
NOTE:
This vehicle has been equipped with a special cold weather shift strategy. This was designed to maximize heater output. This new strategy operates under the following conditions: ambient air temperature at start-up is -4°C (25°F) or below and the engine coolant temperature at start-up is 38°C (100°F) or below. During this condition, the vehicle may experience slightly delayed shifts under light throttle. Medium and heavy throttle shifts will be normal. Once the engine coolant reaches 71°C (160°F) or above, normal shift scheduling will resume. If, during the diagnosing of a delayed shift concern, the concern goes away after the engine coolant reaches 71°C (160°F) or above, this is a normal operation of the special cold weather shift strategy. If this condition does not go away after the engine coolant reaches 71°C (160°F), refer to DIAGNOSIS BY SYMPTOM .
NOTE:
When the battery has been disconnected and reconnected, some abnormal drive symptoms can occur while the vehicle relearns its adaptive strategy. The customer needs to be notified that they may experience slightly different upshifts (either soft or firm) and this is a temporary condition that will eventually return to normal operating condition.
Transmission upshifting is controlled by the PCM. The PCM receives inputs from various engine or vehicle sensors and driver demands to control shift scheduling, shift feel and torque converter clutch (TCC) operation.