Massey Ferguson 04.01.9C – TRANS2: Transmission Input Shaft Speed Sensor Open Circuit (TRANS2)

The transmission controller has detected a break in the electrical circuit (open circuit) or a complete loss of signal from the input shaft speed sensor.

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626

1. 1

   Locate the transmission input shaft speed sensor on the transmission housing and inspect the sensor body for physical damage.

2. 2

   Disconnect the sensor and inspect the connector pins for corrosion, pushed-back pins, or moisture ingress.

3. 3

   Trace the wiring harness from the sensor back to the TRANS2 module. Use a multimeter to check for continuity and ensure there are no broken wires (open circuit) or chafing against the tractor chassis.

4. 4

   Test the inductive sensor's internal resistance across its pins. If it reads completely open (infinite resistance), the sensor itself has failed internally and must be replaced.

1. 1

   Preparation

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and disconnect the negative battery terminal to prevent electrical shorts.

2. 2

   Locate the Sensor

   Identify the transmission input shaft speed sensor on the side of the transmission housing.

3. 3

   Removal

   Depress the locking tab and disconnect the electrical harness from the sensor. Remove the retaining bolt holding the sensor to the transmission casing. Carefully pull the sensor straight out. (Have a rag ready, as a small amount of transmission fluid may weep from the port).

4. 4

   Installation

   Lubricate the O-ring on the new sensor with a small amount of clean transmission fluid. Insert the new sensor into the housing and secure it with the retaining bolt. Reconnect the electrical harness until it clicks into place.

5. 5

   Calibration/Clearing

   Reconnect the battery. Turn the key to the ON position and use a Massey Ferguson diagnostic tool (or the tractor's onboard diagnostic dashboard menu) to clear the 04.01.9C fault code. Perform a short test drive to ensure the transmission shifts smoothly and the code does not return.