Upshift Control & Torque Converter Clutch Apply

The PCM calculates the upshift points based primarily on two inputs: throttle angle and vehicle speed. When the PCM determines that conditions are met for a shift to occur, the PCM commands the shift by closing or opening the ground circuit for the appropriate solenoid.

1. Choose a throttle position of 12, 25 or 50 percent. See SHIFT SPEED SPECIFICATIONS  . All throttle angles shown should be tested to cover the normal driving range.
2. Monitor the following scan tool parameters:
   • Throttle Angle
   • Vehicle Speed
   • Engine Speed
   • Commanded Gear
   • Slip Speed
   • Solenoid States
3. Place the gear selector in the O/D position.
4. Accelerate the vehicle using the chosen throttle angle. Hold the throttle steady.
5. As the transaxle upshifts, note the vehicle speed when the shift occurs for each gear change. There should be a noticeable shift feel or engine speed change within 1 to 2 seconds of the commanded gear change.
6. Compare the shift speeds to the shift speed chart. See SHIFT SPEED SPECIFICATIONS  . Shift speeds may vary slightly due to transmission fluid temperature or hydraulic delays in responding to electronic controls. Note any harsh, soft or delayed shifts or slipping. Note any noise or vibration.
7. Repeat steps  1 - 6 to complete testing for all throttle angles.
8. Check for TCC apply in 3rd and 4th gear.
   • Note the TCC apply point. When the TCC applies, there should be a noticeable drop in engine speed and a drop in slip speed displayed by scan tool to below 100 RPM. If the TCC apply can not be detected, check for DTCs.
   • For TCC apply speeds, see SHIFT SPEED SPECIFICATIONS  .
   • Lightly tap and release the brake pedal. The TCC will release on most applications.