Case IH tCD – Transmission Control Module (TCM): 1 CAN Chip, Data Valid But Below Normal Range

This indicates a communication or voltage issue on the Controller Area Network (CAN) bus, specifically where the data being received by the CAN chip is recognized as valid but falls below the normal operating threshold.

• MXM
• MXM 120
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190
• TM115 through TM165

1. 1

   Check PCU power supply to ensure the Transmission Control Module is receiving the correct voltage and that the battery/alternator output is stable

2. 2

   Inspect CAN bus wiring harness and connectors leading to the Transmission Control Module for corrosion, loose pins, or chafing that could cause a voltage drop

3. 3

   Check for recent component replacements (microprocessor, PWM solenoid valve, potentiometer) or non-volatile memory resets that were performed without a subsequent calibration

1. 1

   Resolve Wiring/Voltage Issues

   Repair any damaged CAN bus wiring or clean corroded connectors at the Transmission Control Module.

2. 2

   Replace the Module (if necessary)

   If the wiring is intact and the power supply is correct, the CAN chip inside the Transmission Control Module may have failed, requiring the replacement of the ECU/PCU.

3. 3

   Perform Transmission/EDC Calibration

   Whether you replaced the controller, a PWM valve, or simply cleared a memory fault, you must perform the H1 Clutch and Synchroniser Calibration: Lower all equipment to the ground and place all shift levers in neutral. Block the front and rear wheels. Press and hold the High and Low range buttons simultaneously, then start the engine. When 'CAL' appears in the transmission display, release the High and Low range buttons. Set the engine speed to 1200 ERPM (± 100). Follow the on-screen prompts to calibrate the clutches.