Case IH 149 – TMF or AUX: Implement feedback #2 out of range High.

The control module is receiving a voltage signal from the implement feedback sensor #2 (usually a potentiometer) that is too high. Specifically, the controller is detecting that the feedback voltage is greater than approximately 4.5 volts on a standard 5-volt reference circuit. This typically indicates a short to power, an open ground circuit, or a failed sensor.

• Magnum
• MX Magnum Series
• TG Series
• Steiger & STX Series (4WD/Quadtrac)
• Maxxum Series

1. 1

   Check the tractor-to-implement wiring harness and the scraper/implement wiring for an open circuit on the ground wire or a short to power on the signal wire.

2. 2

   Back-probe the implement feedback sensor #2 with a multimeter. As the implement moves, the voltage should sweep smoothly (typically between 0.5V and 4.5V). If it is stuck above 4.5V, the sensor is likely internally shorted or lacking ground.

3. 3

   Check the functionality of the remote hydraulic controller and scraper controller to rule out an internal module failure.

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the implement feedback sensor #2 harness connector.

2. 2

   Inspect Connectors

   Look for corrosion, moisture, or pushed-out pins in both the tractor-side and implement-side connectors. Clean with contact cleaner if necessary.

3. 3

   Test the Harness

   Using a multimeter, verify that the sensor is receiving a steady 5V reference and has a solid ground. Test the signal wire for continuity back to the TMF/AUX controller and ensure it is not shorted to a 12V power source.

4. 4

   Replace the Sensor

   If the harness tests good (proper ground and no shorts to power), the implement feedback potentiometer has failed internally and must be replaced.

5. 5

   Recalibrate and Clear Codes

   Install the new sensor, reconnect the harness, and use the tractor's display or a diagnostic service tool to clear the TMF/AUX fault codes. Perform a hitch/implement calibration if required by the specific implement.