Case IH 1002 - UCM – UCM: Radar disconnected

This fault code indicates that the control module has lost communication with the ground speed radar sensor. The radar sensor is responsible for measuring the true ground speed of the tractor, which the system uses for slip control, draft control, and general performance monitoring.

• VESTRUM CVX
• Magnum Series (180, 190, 210, 225, 250, MX210-MX285)
• Maxxum Series (100, 110, 115, 125, 140, MXM120-MXM190, MXU100-MXU135)
• Puma Series (165, 180, 195, 210, 225)
• Steiger / 4WD Series
• Farmall / JX Series (85U, 95U, 105U, JX70U-JX1100U)
• Legacy 51 Series & MX Series

1. 1

   Visually inspect the radar sensor for physical damage. Ensure the sensor face is clean and not obstructed by heavy mud, debris, or crop material.

2. 2

   Inspect the wiring harness leading to the radar sensor for severed wires, rubbing, or rodent damage. Disconnect the sensor and check the connector pins for corrosion, moisture, or pushed-out pins.

3. 3

   Verify continuity in the wiring harness between the radar sensor connector and the UCM/EDC module to rule out a broken wire.

4. 4

   Ensure the radar sensor bracket is not bent. The sensor must be angled correctly toward the ground to read speed accurately.

1. 1

   Power down

   Turn off the tractor, remove the key, and disconnect the negative battery cable to prevent electrical shorts.

2. 2

   Locate the sensor

   Locate the ground speed radar sensor mounted on its bracket beneath the tractor.

3. 3

   Disconnect harness

   Unplug the electrical harness connector from the radar sensor.

4. 4

   Remove sensor

   Remove the mounting bolts/nuts securing the radar sensor to the bracket and remove the old sensor.

5. 5

   Install new sensor

   Mount the new radar sensor onto the bracket and tighten the hardware securely. Ensure it is oriented in the exact same direction/angle as the original.

6. 6

   Reconnect

   Plug the electrical harness back into the new sensor. Reconnect the battery.

7. 7

   Calibrate sensor

   Enter the tractor's calibration menu (via the armrest display or instrument cluster) and perform the ground speed radar calibration. This typically involves driving the tractor over a precisely measured distance (e.g., 400 feet or 100 meters) on a hard, flat surface while the system learns the new sensor's pulse rate.