Massey Ferguson 04.2.55 – Transmission Control Module (TRANS): Transmission Temperature Signal Out Of Range

The controller is receiving a voltage signal from the transmission hydraulic oil temperature sensor that falls outside the normal, expected operating parameters. This typically indicates an electrical fault (such as a short circuit, open circuit, or a failed sensor) rather than an actual mechanical overheating issue, though extreme fluid temperatures can sometimes trigger out-of-range errors.

• 4707
• 4708
• 4709
• 4710
• T4 (2015-2021)
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720

1. 1

   Locate the transmission temperature sensor and visually inspect the electrical connector and wiring harness for physical damage, corrosion, or loose pins.

2. 2

   Use a multimeter to perform a wiring continuity test, checking for an open circuit or a short to ground in the wiring harness between the sensor and the Transmission Control Module (TRANS).

3. 3

   Test the sensor's resistance with a multimeter to see if it matches OEM specifications for the ambient temperature. If it reads completely open (infinite resistance) or shorted (zero resistance), the sensor has failed internally.

4. 4

   Verify the actual temperature and level of the transmission hydraulic fluid to ensure the transmission is not genuinely overheating due to low fluid or a blocked transmission filter.

1. 1

   Locate the Sensor

   The transmission temperature sensor/switch is typically located at the bottom of the transmission casing or near the hydraulic filter housing, depending on your specific series.

2. 2

   Clean the Area

   Thoroughly clean the area around the sensor to prevent dirt and debris from entering the transmission housing when the sensor is removed.

3. 3

   Disconnect the Harness

   Unplug the electrical connector from the sensor.

4. 4

   Prepare for Fluid Loss

   Place a clean drain pan underneath the sensor location. Because the sensor is threaded into the transmission casing, hydraulic fluid will leak out when it is removed.

5. 5

   Remove the Sensor

   Unscrew the faulty temperature sensor.

6. 6

   Install the New Sensor

   Quickly thread the new sensor into the port to minimize fluid loss. Tighten it to the OEM torque specification. (Use a new sealing washer or thread sealant if required by the specific part design).

7. 7

   Reconnect and Refill

   Reconnect the electrical harness. Check the transmission fluid level via the sight glass or dipstick and top up any fluid that was lost during the swap.

8. 8

   Clear Codes

   Turn the key on and use a diagnostic tool to clear the 04.2.55 fault code from the TRANS module. Test drive the tractor to ensure the code does not return.