Case IH 180 – TMF (Tractor Multi-Function Controller): The PTO is receiving signals from the Shaft Size Sensor on a single speed PTO configuration.

The controller is programmed for a single-speed PTO (which does not use a shaft size sensor to determine 540 vs 1000 RPM), but it is actively receiving a frequency signal on the shaft size sensor circuit. This typically indicates that the PTO Shaft Speed Sensor and the PTO Shaft Size Sensor connectors have been accidentally swapped, the wiring harness is shorted, or the controller is incorrectly configured.

• Magnum
• Case IH MX Magnum Tractors
• Case IH Magnum Tractors
• TG Series Tractors
• T8000 Series Tractors

1. 1

   Verify that Connector No. 145 (PTO Shaft Speed Sensor) and Connector No. 146 (PTO Dual Speed/Size Sensor) are not plugged into the wrong sensors.

2. 2

   Check continuity from Pin 10 of controller connector C056 to Pin A of sensor connector C145.

3. 3

   Check continuity from Pin 12 of connector C056 to Pin A of connector C146, and to Pin A of C336.

4. 4

   Check continuity from Pin B of connectors C145 and C336 to the chassis ground.

5. 5

   Measure the resistance of both the speed sensor and the shaft size sensor (each should be approximately 3 K ohms).

1. 1

   Inspect the Wiring

   Locate the PTO sensors at the top rear of the transmission. Inspect the wiring harness for any rubbing, breaks, or shorts to ground.

2. 2

   Verify Connections

   Ensure the wiring connectors are routed to their correct respective sensors. If they were swapped during a recent service, swap them back to their correct positions and clear the code.

3. 3

   Test the Sensors

   Unplug the sensors and measure the resistance across the sensor pins. If the shaft size sensor or speed sensor does not read ~3,000 ohms, it has failed internally and must be replaced.

4. 4

   Repair the Harness

   If the sensors test good but the continuity checks from the diagnostic steps fail, locate the break or short in the harness between the transmission and the TMF controller and repair the wires.

5. 5

   Verify Configuration

   If the wiring and sensors are perfect, verify via the tractor monitor or diagnostic tool that the PTO controller memory has not lost its configuration and is correctly programmed for the physical PTO installed on the tractor.