Massey Ferguson 04.01.56 – TRANS: Transmission Filter Blockage Sensor Issue

The controller is receiving an abnormal signal from the transmission filter blockage sensor (designated in Massey Ferguson electrical diagrams as sensor X20). The system has detected a pressure drop or restriction across the transmission/hydraulic filter, indicating that the filter is clogged, the oil is too thick to pass through efficiently, or there is an electrical fault (short/open circuit) in the sensor itself.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 7714S
• 7719S

1. 1

   Check oil temperature: Cold, thick hydraulic/transmission oil can cause a false blockage reading. Allow the tractor to reach normal operating temperature to see if the code clears.

2. 2

   Inspect wiring and connector: Locate the X20 transmission filter blockage sensor on the side of the transmission housing. Inspect the wiring harness and connector for corrosion, broken wires, or loose pins.

3. 3

   Check filter for contamination (Crucial): Remove and inspect the transmission filter. A blocked transmission filter is a common early warning sign that the internal brake discs are breaking up. If fibrous friction material or metal filings are found, do not continue driving the tractor.

1. 1

   Park the tractor on a level surface, lower all implements, and turn off the engine.

2. 2

   If the X20 sensor wiring was found to be damaged during diagnostics, repair the harness or replace the connector plug.

3. 3

   Place a large drain pan under the transmission filter housing and drain the fluid.

4. 4

   Unbolt the transmission filter housing plate and remove the hydraulic/transmission filter element.

5. 5

   Inspect the filter for heavy contamination.

   If brake material or metal shavings are present, the rear axle/brakes must be stripped and repaired, and the entire hydraulic system must be flushed.

6. 6

   If the filter is simply old or clogged with normal dirt, install a new genuine Massey Ferguson transmission filter element and replace the housing seals.

7. 7

   If the filter was perfectly clean and the wiring is intact, the X20 sensor has failed. Unscrew the old filter blockage sensor from the transmission housing and install a new one.

8. 8

   Top off the transmission fluid to the correct level using approved Massey Ferguson transmission/hydraulic oil.

9. 9

   Start the tractor, check the filter housing for leaks, and use the dashboard terminal to clear the stored 04.01.56 fault code.