Case IH U12 – Electronic Management Unit (EMU) / Transmission Controller: Auto Calibration Procedure Stopped / Vehicle Not Stationary

This code is triggered during the transmission or clutch calibration procedure. The system aborts the calibration because it detects that the tractor is moving, or the system prerequisites (like the handbrake being engaged) have not been met.

• Puma/Mid Range Magnum
• Maxxum
• MXM
• Case IH MXM Series (120, 130, 140, 155, 175, 190)
• Case IH Puma Series (115, 125, 140, 155, 165, 180, 195, 210, 225)
• Case IH Maxxum Series
• Case IH MXU Series

1. 1

   Verify that the handbrake is fully engaged and that the handbrake switch is functioning correctly.

2. 2

   Check the rear axle speed sensor for faults, which can send an erroneous speed signal to the EMU tricking it into thinking the tractor is moving.

3. 3

   Inspect the wiring harness connecting the rear axle speed sensor to the EMU for open circuits, shorts, or physical damage.

1. 1

   Secure the Vehicle

   Park the tractor on level ground, place all shift levers in neutral, and block the wheels (front and rear).

2. 2

   Verify Prerequisites

   Ensure the handbrake is fully applied.

3. 3

   Inspect/Replace the Sensor

   If the handbrake circuit is confirmed good, locate the rear axle speed sensor on the rear axle housing. Disconnect the electrical connector and inspect the pins for corrosion.

4. 4

   Install New Sensor

   If the sensor is faulty, remove it from the housing, install the replacement speed sensor, and reconnect the wiring harness.

5. 5

   Re-attempt Calibration

   Restart the transmission/clutch calibration procedure. Ensure all environmental prerequisites are met: Transmission oil temperature must be between 20°C and 50°C, Engine speed set to 1200 RPM, Air conditioning switched off, and All electrical and hydraulic services deselected.