New Holland TRANS 126 – Transmission Control Unit (TCU) / TRANS: Even clutch is not calibrated

The transmission controller lacks valid calibration data for the "Even" clutch pack. This can happen if a calibration routine was interrupted, if the EEPROM memory was cleared/corrupted, or if a mechanical/electrical issue prevented the controller from successfully completing the calibration sequence for this specific clutch.

• TG Series
• TG210
• TG230
• TG255
• TG285
• TG305
• T7 Series
• T8 Series
• T9 Series
• T8000
• T9000
• T8.xxx
• T9.xxx
• TJ Series
• TM Series

1. 1

   Check for active electrical fault codes for the Even clutch solenoid (e.g., TRANS 104 or TRANS 114). Resolve any wiring or solenoid issues before attempting calibration.

2. 2

   Ensure transmission fluid is warmed up to the stipulated operating temperature to avoid 'Cold Oil Temp' or 'Hot Oil Temp' calibration blocks.

3. 3

   Verify safety setup: park the tractor on level ground away from obstacles, apply the parking brake, chock the wheels, and ensure the ground speed display reads zero.

1. 1

   Start the tractor and warm the transmission fluid to normal operating temperature.

   This is required before calibration can begin.

2. 2

   Enter the transmission calibration mode.

   Often displayed as "cal" or "cc" on the instrument cluster.

3. 3

   Navigate to the individual clutch calibration menu and select the Even Clutch, or initiate the Automatic Clutch Calibration sequence.

4. 4

   Observe the calibration process.

   The screen will display 'Even 0 mA' when the calibration begins. The controller will slowly increase the electrical current (mA) to the Even clutch solenoid until it detects a slight drop in engine RPM (engine droop), indicating the clutch has engaged.

5. 5

   Verify successful calibration.

   Once successfully calibrated, the screen will display '*Even mA' along with the final calibration value.

6. 6

   Press the Enter or PROG key to save the value and move to the next clutch.

7. 7

   Reduce engine speed to low idle, turn the keyswitch to the OFF position, and leave it off for at least 15 seconds.

   Crucial Final Step: This writes the new calibration values to the controller's EEPROM memory.