Case IH U24 – Transmission Control Module: Incorrect range selection

This code is typically triggered during a transmission calibration or startup procedure when the system detects that the range lever is in neutral or low range, rather than the required high range (or gear 5, depending on the specific transmission).

• JXC
• Case IH Maxxum series (MXM 120, 130, 140, 155, 175, 190)
• Case IH MX series (MX170, MX210, MX230, MX255, MX285)
• Case IH Puma series
• Case IH Magnum series
• Case IH TN series

1. 1

   Verify that the operator has moved the range lever out of neutral and into the highest range (or shifted the 4/5 lever into 5) as required by the procedure

2. 2

   Use the tractor's H-Menu (H5 switch diagnostics on the instrument cluster) to detect if the low range switch is connected and registering lever movement

3. 3

   Inspect the mechanical gear linkage to ensure it is not out of adjustment, sticking, or broken

4. 4

   Inspect the wiring harness and connectors for the transmission low range switch for damage, corrosion, or open circuits

1. 1

   Correct Lever Position

   Shift the range lever out of low/neutral and into the highest range. Re-attempt the tractor startup or transmission calibration procedure. If the code clears, it was simply an operator sequence error.

2. 2

   Adjust Gear Linkage

   If the lever is physically moved but the code persists, adjust the transmission gear linkage. Ensure the linkage fully engages the synchronizer and properly actuates the range switch.

3. 3

   Test the Low Range Switch

   Access the transmission low range switch (typically located on the transmission housing). Disconnect the switch and test it for proper resistance/continuity when the lever is moved. If the switch does not change state, it has failed internally.

4. 4

   Repair Wiring

   If the switch tests good, trace the wiring from the switch to the Transmission TCU. Repair any broken wires or replace damaged connector pins.

5. 5

   Replace Faulty Components

   Replace the low range switch or worn linkage components if they fail the above tests.

6. 6

   Recalibrate

   After repairs are made, perform a full transmission clutch calibration to ensure the system recognizes the correct lever positions and clutch fill times.