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Road Testing Vehicle

Shift Point Road Test

Special Tool(s):





This test verifies that the shift control system is operating correctly.
1. Bring engine and transmission up to normal operating temperature.
2. Operate vehicle with transmission range selector lever in D position.
3. Apply minimum throttle and observe speeds at which upshift occurs and the torque converter engages. Refer to the Shift Speeds chart.
4. With the transmission in D, move the range selector lever into the manual 3 position. The transmission should downshift to 4th gear. Release the accelerator pedal; engine braking should occur.
5. Press the accelerator pedal to floor, wide open throttle (WOT). Transmission should shift from 4th to 3rd, depending on vehicle speed. The torque converter clutch (TCC) should disengage and then reapply.
6. With the transmission in D position and speed above 80 km/h (50 mph) and less than half throttle, move the transmission range selector lever from D position to manual 2 position and remove pressure from the accelerator pedal. The transmission should downshift into 2nd gear. With the vehicle remaining in manual 2 position, move the transmission range selector lever into manual 1 position and release the accelerator pedal. The transmission should downshift into 1st gear at speeds below approximately 45 - 56 km/h (28 - 35 mph).
7. If the transmission fails to upshift/downshift or the TCC does not apply and release, refer to Diagnosis By Symptom. Diagnosis By Symptom

Shift Speeds:





Road Test - Adaptive Drive Cycle

NOTE: Using the scan tool, clear the adaptive table before conducting an adaptive drive cycle test.

NOTE: All adaptive drive cycle tests are carried out with the transmission fluid temperature at normal operating temperature 80°C-82°C (175°F-180°F).

NOTE: All adaptive drive cycle test are carried out with the range selector lever in the D position.

This test will begin the adaptive learning schedule to provide a better shift quality and shift feel.

1. Verify that the transmission fluid temperature (TFT) PID is above 80°C (175°F).
2. Clear transmission control module (TCM) keep alive memory (KAM) and adaptive table using the scan tool.
3. Accelerate from rest with light throttle. The 1-2, 2-3 and 3-4 shifts must occur at engine speeds between 1300 - 1800 rpm.
4. Continue to accelerate gently to 80 km/h (50 mph) so that the transmission shifts into 5th gear.
5. Brake gently to a complete stop and hold foot on brake for at least 15 seconds.
6. Repeat Steps 3-6 a total of 5 times.