Massey Ferguson 04.02.90 – Transmission Controller (TRANS1): Issue With Speed Sensor Values (TRANS1)

The transmission controller is receiving erratic, implausible, or missing signals from the transmission speed sensor. The system relies on this sensor to monitor the rotational speed of the transmission shafts to manage shifting and clutch engagement properly.

• 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

1. 1

   Inspect the wiring harness leading to the transmission speed sensor for chafed wires, melted insulation, or physical damage

2. 2

   Disconnect the sensor and check the pins for corrosion, moisture, or loose terminals

3. 3

   Test the sensor's internal resistance using a multimeter (should read approximately 540 Ohms; open or shorted indicates internal failure)

4. 4

   Verify if there are other CAN BUS communication codes (such as 04.02.94) which might indicate a broader harness or module communication failure rather than a localized sensor failure

1. 1

   Locate the Sensor

   Locate the transmission speed sensor on the transmission housing.

2. 2

   Clean the Area

   Thoroughly clean the area around the sensor base to prevent dirt or debris from falling into the transmission housing when the sensor is removed.

3. 3

   Disconnect

   Unplug the electrical connector from the sensor pigtail/cable.

4. 4

   Remove the Sensor

   Using a 24mm wrench, unthread the faulty sensor from the housing (the sensor uses an M20x1.5 thread).

5. 5

   Install the New Sensor

   Thread the new sensor into the housing. Ensure the sealing ring/O-ring is properly seated. Tighten carefully to avoid stripping the threads.

6. 6

   Reconnect

   Plug the electrical connector back into the machine's harness and ensure the locking tab clicks into place. Route the cable (which is typically around 345mm - 440mm long) safely away from moving parts.

7. 7

   Clear Codes

   Turn on the tractor, clear the stored fault codes via the diagnostic interface or monitor, and perform a test drive to verify that the transmission shifts smoothly and the speed values read correctly.