Case IH F45 – Transmission Controller or CCU (Chassis Control Unit): Low/High Range Synchronizer Potentiometer Out Of Calibrated Range

This indicates that the transmission controller is receiving a voltage signal from the low/high range synchronizer potentiometer that falls outside of the expected, previously calibrated parameters.

• MXM
• Case IH MXM Series (MXM 120, 130, 140, 155, 175, 190)
• Case IH Magnum Series (MX210, MX230, MX255, MX285)
• Case IH Maxxum Series
• Case IH Puma Series (e.g., Puma 140)
• Case IH Steiger Series

1. 1

   Inspect Connectors: Check the low/high range synchronizer potentiometer connector (designated as X-666) and the CCU connector (X-097). Ensure the connectors are fully seated, not damaged, the pins are in the correct position, and the fit is tight.

2. 2

   Check Reference Voltage: Disconnect connector X-666. Turn the ignition switch to the ON position and measure the voltage at the connector to ensure the potentiometer is receiving a steady 5-Volt reference signal from the controller.

3. 3

   Test the Solenoid: Check the low range clutch solenoid by measuring the electrical resistance between solenoid terminal 1 and terminal 2. The resistance should measure between 8 and 11 Ohms.

1. 1

   Wiring Repair

   If the visual inspection or voltage test reveals a fault in the wiring harness or connectors (X-666 or X-097), repair or replace the damaged wiring/pins as required.

2. 2

   Solenoid Replacement

   If the resistance of the low range clutch solenoid is not between 8 and 11 Ohms, remove and replace the solenoid.

3. 3

   Potentiometer Replacement

   If the wiring is intact, the 5V reference is present, and the solenoid tests fine, the synchronizer potentiometer itself has likely failed internally and must be replaced.

4. 4

   Transmission Calibration

   Because the code specifically flags the sensor as being 'Out Of Calibrated Range,' you must perform a transmission clutch calibration procedure via the tractor's H-Menu/Calibration mode after any repairs or parts replacements are made.