Massey Ferguson 04.X.55 – TRANS: Transmission Temperature Signal Out Of Range (TRANS)

The transmission controller is receiving an electrical signal (voltage or resistance) from the transmission hydraulic oil temperature sensor that falls outside the programmed normal operating parameters. This typically indicates an electrical fault—such as an open circuit, a short to ground, a damaged wiring harness, or a completely failed sensor—rather than an actual mechanical overheating condition.

• 4707
• 4708
• 4709
• 4710
• T4 (2015-2021)
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7714
• 7715
• 7716
• 7718
• 7719
• 7720
• 8600 Series

1. 1

   Check the transmission/hydraulic fluid level via the sight glass or dipstick on level ground, as low fluid can cause erratic temperature readings.

2. 2

   Inspect the transmission temperature sensor electrical connector and the wiring harness leading back to the TRANS module for chafing, breaks, corrosion, or loose pins.

3. 3

   Perform a circuit test by turning the ignition switch on, disconnecting the sender wire, and grounding the terminal with a jumper wire. If the temperature gauge sweeps to full scale, the wiring is intact and the sensor is likely faulty.

4. 4

   Test the sensor resistance (ohms) with a multimeter at room temperature or suspended in heated water. If it reads completely open (infinite resistance) or shorted (zero resistance), the sensor is dead.

1. 1

   Preparation

   Park the tractor on a flat surface, lower all hydraulic implements to relieve system pressure, turn off the engine, and allow the transmission fluid to cool.

2. 2

   Locate the Sensor

   Find the transmission temperature sensor, which is typically threaded into the bottom or lower side of the transmission casing/hydraulic sump.

3. 3

   Clean the Area

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

4. 4

   Disconnect

   Unplug the electrical wiring harness from the sensor.

5. 5

   Removal

   Place a clean drain pan underneath the sensor location, as some hydraulic fluid will escape. Use an appropriate wrench or deep socket to unthread and remove the faulty sensor.

6. 6

   Installation

   Thread the new OEM temperature sensor into the casing. Tighten it to the manufacturer's specified torque (do not overtighten, as the brass/plastic housings can break).

7. 7

   Reconnection

   Reconnect the electrical harness, ensuring the connector clicks securely into place.

8. 8

   Fluid Top-Off

   Check the hydraulic/transmission fluid level and top it off with the manufacturer-recommended fluid (e.g., AGCO Parts Transmission Oil) to replace any fluid lost during the swap.

9. 9

   Clear Codes

   Use a diagnostic tool to clear the 04.X.55 fault code from the TRANS module, then start the tractor and verify the code does not return.