Massey Ferguson 13.X.1A – Transmission Control Module (TRANS1): Issue With Park Lock Proximity Switch On The Axle Dyna VT (TRANS1)

Signal error or discrepancy between the sensor's reported status and the requested state of the ParkLock system. The system detects that the proximity switch (X21) is not providing the expected electrical signal when the park lock is engaged or disengaged.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• MF 6600 Series (6614, 6615, 6616)
• MF 7400 Series
• MF 7600 Series (7615, 7618, 7624)
• MF 7700 Series (7715, 7720, 7726)
• MF 8400 and 8600 Series (8670, 8690)

1. 1

   Verify the active code on the Datatronic screen or dashboard

2. 2

   Inspect the Park Lock Proximity Switch (Sensor X21) on the axle/transmission housing for damaged wires, corrosion, or loose pins

3. 3

   Check for physical damage, mud, or metallic debris around the proximity switch that might interfere with its magnetic/proximity sensing capabilities

4. 4

   Use a multimeter to check the sensor circuit for an open circuit, a short to ground (-), or a short to +12V power

5. 5

   Check the ParkLock hydraulic system pressure sensor (X35) and braking pressure sensor (X135) readings to verify if hydraulic pressure is failing to physically move the lock

1. 1

   Secure the Machine

   Park the tractor on a level surface, turn off the engine, and safely chock the wheels. Do not rely on the ParkLock during this repair.

2. 2

   Locate the Sensor

   Find the X21 Park Lock Proximity Switch on the axle housing.

3. 3

   Disconnect

   Unplug the electrical connector from the switch.

4. 4

   Clean

   Thoroughly clean the area around the switch base to prevent dirt from falling into the transmission/axle housing when the sensor is removed.

5. 5

   Remove

   Unscrew and extract the faulty proximity switch.

6. 6

   Install

   Thread the new proximity switch into the housing. Tighten it to the manufacturer's specified torque (do not overtighten, as proximity sensors are easily damaged).

7. 7

   Reconnect

   Plug in the electrical connector, ensuring the weather seal clicks into place.

8. 8

   Clear Codes

   Turn the key on and use a diagnostic tool (or the tractor's onboard diagnostic menu) to clear the 13.X.1A fault code.

9. 9

   Test

   Start the tractor and test the ParkLock function by engaging and disengaging it. Ensure the tractor holds securely and no new codes are generated.