Shift Point Road Test
Road Testing VehicleThe following Shift Point Road Test and Torque Converter Clutch Operation Test provide diagnostic information on transmission shift controls and torque converter operation.
Refer to Component Tests for Torque Converter Diagnosis. Component Tests
Shift Point Road Test
NOTE: Always drive the vehicle in a safe manner according to driving conditions and obey all traffic laws.
This test verifies that the shift control system is operating correctly.
1. Bring engine and transmission up to normal operating temperature.
2. Operate the vehicle with the transmission range selector lever in (D).
3. Apply minimum throttle and observe the speeds at which the upshift occurs and the torque converter engages.
4. With the transmission in OVERDRIVE (fourth gear), depress the Transmission Control Switch (TCS). The transmission should downshift to third gear. Remove your foot from the accelerator pedal; engine braking should occur.
5. Press the accelerator pedal to the floor (wide-open throttle). The transmission should shift from third to second gear or third to first, depending on vehicle speed. The Torque Converter Clutch (TCC) should disengage and then reapply.
6. With vehicle in (D) range above 80 km/h (50 mph) and less than half throttle, move the transmission range selector lever from (D) range to MANUAL 2 range and remove your foot from the accelerator pedal. The transmission should immediately downshift into second gear. With the vehicle remaining in MANUAL 2 range, move the transmission range selector lever into MANUAL 1 range. Transmission should downshift into first gear at speeds BELOW 52 km/h (38 mph).
7. If the transmission fails to upshift/downshift or the TCC does not apply and release, refer to Diagnosis By Symptom for concern diagnosis.
Shift Speed Chart
NOTE: AD gasoline applications have new adaptive shift strategies. Whenever the vehicle's battery has been disconnected for any type of service or repairs, the strategy parameters that are stored in the Keep Alive Memory (KAM) will be lost. The strategy will start to relearn once the battery is reconnected and the vehicle is driven. This is a temporary condition and will return to normal operating condition once the Powertrain Control Module(PCM) relearns all the parameters fro the driving conditions. There is no time frame set for this process. If this concern is present during down shifts or converter clutch apply, it is not the shift strategy and will require diagnosis.
The customer needs to be notified that they may experience slightly different upshifts (either soft or firm) and that this condition is temporary and will eventually return to normal operating condition.
NOTE: D is the same as (D) with the transmission control switch actuated (light on).
Shift Speeds - Approximate mph