Case IH 5044 (1883.04) - DEC – Transmission Control Unit (TCU) or Central Control Module (CCM) / EPL Module: Rear PTO Speed Sensor - Short To Ground

The control module has detected a short to ground (0 volts) in the circuit for the rear Power Take-Off (PTO) speed sensor. When this occurs, the system is unable to read the rotational speed of the rear PTO shaft, which can disable PTO functions or auto-PTO features.

• VESTRUM CVX
• Puma 165
• Puma 180
• Puma 195
• Puma 210
• Puma 225
• Puma 240 CVT
• Maxxum 115
• Maxxum 125
• Farmall 115U
• Magnum MX210
• Magnum MX230
• Magnum MX255
• Magnum MX285

1. 1

   Visually inspect the Rear PTO Speed Sensor (connector X251) on the rear right-hand side of the transmission housing. Check the wiring harness for chafing, melting, or pinched wires shorting against the tractor chassis.

2. 2

   Verify the sensor pinout: Pin 1 (Green) is PTO Supply, Pin 2 (Orange) is Signal, and Pin 3 (Black/White) is Sensor Ground.

3. 3

   Perform a disconnect test to isolate the cause: Disconnect the sensor and turn the key ON. If the code changes from 5044 to 5027 (Open Circuit), the sensor is internally shorted and must be replaced. If code 5044 remains active, the signal wire (Pin 2) is shorted to ground in the harness between the sensor and the ECU.

1. 1

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and disconnect the battery ground cable.

2. 2

   Locate the Rear PTO Speed Sensor on the rear transmission housing.

3. 3

   Thoroughly clean the area around the sensor to prevent dirt or debris from falling into the transmission fluid.

4. 4

   Disconnect the 3-pin electrical connector from the sensor.

5. 5

   Remove the retaining bolt(s) securing the sensor to the housing.

6. 6

   Carefully pull the faulty sensor out of the transmission bore.

   Have a rag ready, as a small amount of hydraulic/transmission fluid may seep out.

7. 7

   Lubricate the O-ring on the new sensor with clean transmission fluid.

8. 8

   Insert the new sensor into the housing and torque the retaining bolt to OEM specifications.

9. 9

   Reconnect the electrical harness, ensuring the locking tab clicks into place.

10. 10

    Reconnect the battery, start the tractor, and engage the rear PTO to verify the speed registers on the dash and the fault code moves to an inactive state.