Massey Ferguson 04.X.89 – TRANS: Transmission Oil Temperature Signal Issue

This indicates an electrical fault—such as an open circuit, a short to ground, or a short to power—in the circuit for the transmission oil temperature sensor. Because it is a signal issue, the controller is receiving an erratic, missing, or out-of-range voltage reading from the sensor rather than strictly detecting a mechanical overheating event.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626

1. 1

   Access the Dash Control Center (DCC) on diagnostic screen 1 to view live transmission temperature. Look for erratic or extreme default values (e.g., below -24°C or above 150°C).

2. 2

   Inspect the wiring harness leading to the transmission oil temperature sensor (component X19 or 1S2) for chafed wires, corrosion in connector pins, or loose connections.

3. 3

   Use a multimeter to check for continuity between the sensor connector and the TRANS module, testing for a short to ground (voltage too low) or an open circuit/short to power (voltage too high).

4. 4

   Verify the transmission fluid level and ensure the transmission oil cooler and filters are not plugged, as severe fluid degradation can impact sensor readings.

1. 1

   Power Down

   Turn off the tractor, place all gears in neutral, and disconnect the battery to prevent electrical shorts during repair.

2. 2

   Locate the Sensor

   Locate the transmission oil temperature sensor on the transmission housing (refer to your specific model's service manual for the exact port location).

3. 3

   Remove the Sensor

   Disconnect the electrical plug from the sensor. Place a drain pan underneath to catch any hydraulic/transmission fluid that may escape, then unthread the sensor from the housing.

4. 4

   Install the New Sensor

   Thread the new temperature sensor into the transmission housing and tighten it to the manufacturer's specified torque.

5. 5

   Reconnect

   Plug the electrical harness back into the sensor. Ensure the connector clicks into place securely.

6. 6

   Fluid Check

   Top off the transmission/hydraulic fluid to replace any that was lost during the swap.

7. 7

   Clear Codes

   Reconnect the battery. Turn the ignition on and use a specialized diagnostic tool or the tractor's onboard diagnostic menu to clear the 04.X.89 DTC.

8. 8

   Test Operation

   Start the tractor and allow it to warm up. Verify that the transmission temperature registers correctly on the dash and that the fault code does not return.