Case IH 1035 – Hitch / ETC (Electronic Tractor Control) / TCU (Tractor Control Unit): Percent slip error

The Percent slip received from ETC indicates failure condition. The tractor calculates wheel slip by comparing the theoretical speed (measured by the wheel speed/transmission sensors) against the actual true ground speed (measured by the ground speed radar sensor). When the difference between these two values falls outside of plausible operating parameters, or if the data is missing/corrupted over the CAN data bus, the system flags a failure condition.

• Magnum
• Steiger T4B
• Magnum Series
• Steiger Series
• Quadtrac Series
• Maxxum Series
• Puma Series

1. 1

   Inspect the ground speed radar sensor (usually mounted under the cab or chassis facing the ground) for heavy mud, crop debris, or physical damage blocking the radar signal.

2. 2

   Inspect the electrical connectors at the radar sensor, the wheel speed sensors, and the TCU. Ensure the connectors are fully seated, not damaged, and the pins are tight and free of corrosion.

3. 3

   Use a multimeter to check the sensor circuits for continuity. Check for an open circuit, a short to ground, or a short to B+ power between the sensors, the instrument controller, and the TCU.

4. 4

   Verify that the instrument controller is properly communicating with the ETC/TCU over the data bus, as a CAN failure can also trigger this code.

1. 1

   Clean the Radar

   If the ground speed radar is obstructed by mud or debris, thoroughly clean the face of the sensor. A blocked radar will report 0 mph ground speed, causing an immediate 100% slip error when the wheels are moving.

2. 2

   Repair Wiring

   If the multimeter tests reveal a short or open circuit in the harness, repair or replace the damaged section of the wiring harness.

3. 3

   Replace Faulty Sensors

   If the wiring is intact but the radar sensor or wheel speed sensor fails to output the correct voltage/frequency (or is physically destroyed), remove the mounting hardware and replace the defective sensor.

4. 4

   Recalibrate

   After replacing a radar or wheel speed sensor, perform a slip/radar calibration procedure via the tractor's Pro 700/1200 display to ensure the new sensor accurately matches the tire size and mounting angle.

5. 5

   Clear Codes and Test

   Clear the inactive fault code 1035 from the TCU. Test drive the tractor under a draft load to verify that the percent slip is calculating correctly and the fault does not return.