A Look At Ford and GM’s Jointly Built 6T40 Transmission
In this last and final article of this series, we will be looking at the Transmission Adaptive Values Learn. As most know by now, this is a series of tests that are run to allow the transmission control module (TCM) to learn individual clutch characteristics.
Transmission Adaptive Values Learn, as most know by now, is a series of tests that are run to allow the transmission control module (TCM) to learn individual clutch characteristics. Once the clutch data is learned, Transmission Adaptive Values Learn translates it into the adaptive data cells, which the TCM uses for clutch control during shifts. The scan tool provides initiation of the Transmission Adaptive Values Learn procedure. This procedure is to be used following transmission repair. The Transmission Adaptive Values Learn procedure must be performed when one of the following repairs have been made to the vehicle. Failure to perform the procedure after one of the following repairs may result in poor transmission performance, as well as transmission DTCs being set:
- Transmission internal service/overhaul
- Valve body repair or replacement
- Control solenoid valve assembly replacement
- TCM software/calibration update
- Any service in response to a shift quality concern
Note: Ensure the following conditions are met before performing the Transmission Adaptive Values Learn procedure:
- Drive wheels are blocked
- Parking brake is applied
- Service brake is applied
- Zero percent throttle and no external engine RPM control
Transmission fluid temperature is between values listed below, if you attempt to run the test above or below these temperatures, the test will not start:
- MY 2011 and prior 70-95°C (158-203°F)
- MY 2012 Gen 1 70-95°C (158-203°F)
- MY 2012 Gen 2 64-95°C (147-203°F)
- MY 2013 Gen 1 70-95°C (158-203°F)
- MY 2013 Gen 2 64-76°C (147-169°F)
- MY 2014 and later 64-76°C (147-169°F)
Transmission gear selector has been cycled from park to reverse three times in order to purge air from the reverse clutches.
Transmission Adaptive Values Learn will abort if the transmission fluid temperature increases to the values listed below:
- MY 2011 and prior 110°C (230°F)
- MY 2012 Gen 1 110°C (230°F)
- MY 2012 Gen 2 100°C (212°F)
- MY 2013 Gen 1 110°C (230°F)
- MY 2013 Gen 2 86°C (187°F)
- MY 2014 and later 86°C (187°F)
Note: If at any time during the procedure, required conditions are not met, Transmission Adaptive Values Learn Adapts may abort and the process may need to be started again from the beginning. If this occurs, the transmission will be left in a neutral state until the controller is shut down, key OFF and the scan tool is removed. Wait for more than 30 seconds prior to re-try procedure. If the procedure repeatedly fails, a limit that engineering set is being exceeded and there is possibly a transmission hardware issue.
- Use the scan tool to navigate to Transmission Adaptive Values Learn by selecting the following:
- 1.1. Module Diagnostics
- 1.2 Transmission Control Module
- 1.3 Configurations/Reset Functions
- 1.4 Transmission Adaptive Values Learn
Note: If at any time during the procedure, required conditions are not met, Transmission Adaptive Values Learn may abort and the process may need to be started again from the beginning.
- Use the scan tool to perform the Transmission Adaptive Values Learn procedure. As the procedure is being performed, the scan tool data display will provide operator instructions. Follow the scan tool instructions, as required.
- Once the procedure is complete, shut OFF the engine and power down the TCM. You will lose communication to the scan tool.
- Restart the engine. This will complete the Transmission Adaptive Values Learn procedure.
Note: When the Transmission Adaptive Values Learn procedure is completed, the transmission will remain in a neutral state until the controller shuts down. If after 1-2 minutes of sitting, with the key OFF and scan tool removed, the vehicle remains in a neutral state, disconnect the battery and wait 5-10 minutes and then hook the battery back up. Reverse and drive should return.
If the Transmission Adaptive Values Learn will not run and the above stated conditions have been met, ensure the following:
Note: The generation of transmission can be determined by using a scan tool to check for Specific DTC P0842. If DTC does not show Invalid, the transmission is Gen 1. If DTC shows Invalid, transmission is Gen 2.
- Determine if transmission is Gen 1 or Gen 2.
- Verify vehicle model year.
- Verify transmission fluid temperature is between the temperatures listed above for the vehicle model year and generation of transmission.
- Brakes and brake switch are functioning properly (Perform Brake Pedal Position Sensor Learn procedure if necessary).
- No active DTCs
- Closed throttle and engine RPM increases above 1,500 RPM while at entrance of the test
- Park/neutral position switch is properly adjusted and functioning
- Line pressure control is able to provide 1,000 kPa and is within specifications
- Vehicle is not moving or vibrating excessively
- Clutches are properly assembled
Brake Pedal Position Sensor Learn
Note: Do not apply the brake pedal during the brake pedal position sensor calibration procedure. Any movement of the brake pedal during this procedure will cause the calibration procedure to fail. If this occurs, the brake pedal position sensor calibration must be repeated. Brake pedal position sensor calibration must be performed after the brake pedal position sensor, body control module (BCM), or engine control module (ECM) have been serviced. The calibration procedure will set the brake pedal position sensor home value. This value is used by the BCM and ECM to determine the action of the driver applying the brake system and to provide this information to the vehicle subsystems via serial data.
Calibration Procedure:
- Apply the parking brake.
- Ignition ON, engine OFF, place the transmission in the PARK position for automatic transmission or NEUTRAL position for manual transmission.
- Install a scan tool.
- Clear all DTCs before proceeding.
- Navigate to the Configuration/Reset Functions menu of the BCM.
- Select the Brake Pedal Position Sensor Learn procedure and follow the directions displayed on the screen.
- Navigate to the Configuration/Reset Functions menu of the ECM.
- Select the Learn Functions menu.
- Select the Brake Pedal Position Sensor Learn procedure and follow the directions displayed on the screen.
We hope that this entire series broken down into 4 parts has been extremely helpful and useful. You can find the other article sections below: