Massey Ferguson 13.03.1A – TRANS1: Issue With Park Lock Proximity Switch On The Axle

The transmission control system is receiving an abnormal, missing, or out-of-range signal from the proximity switch responsible for monitoring whether the mechanical Park Lock on the axle is engaged or disengaged. This can be caused by a failed sensor, a wiring issue (open or short circuit), or the sensor being physically out of adjustment (incorrect air gap).

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• MF 7600 Series (e.g., 7614, 7615, 7618, 7624)
• MF 7700 / 7700S Series (e.g., 7715, 7718, 7720, 7726)
• MF 6S Series
• MF 7S Series
• MF 8S Series

1. 1

   Visually inspect the Park Lock Proximity Switch on the axle housing, its electrical connector, and the wiring harness leading back to the TRANS1 module for physical damage, corrosion, or loose pins.

2. 2

   Check the sensor air gap and mounting to see if the sensor has backed out, become loose, or if debris is interfering with the sensor face.

3. 3

   Perform a wiring continuity test using a multimeter between the proximity switch connector and the TRANS1 ECU to check for continuity, short-to-ground, or short-to-power.

4. 4

   Perform a sensor state test using a diagnostic tool (like AGCO EDT) by monitoring live data while engaging and disengaging the park lock to see if the sensor state changes.

1. 1

   Preparation

   Park the tractor on a flat, level surface. Chock the wheels securely, as you will be working on the park lock system. Turn off the engine and disconnect the battery.

2. 2

   Locate the Sensor

   Locate the Park Lock Proximity Switch on the axle/transmission housing.

3. 3

   Disconnect

   Unplug the electrical connector from the proximity switch.

4. 4

   Clean the Area

   Thoroughly clean the area around the sensor base to prevent dirt or debris from falling into the axle housing when the sensor is removed.

5. 5

   Remove the Sensor

   Loosen the lock nut (if equipped) and unscrew the proximity switch from the housing.

6. 6

   Install the New Sensor

   Thread the new proximity switch into the housing. Adjust the sensor depth/air gap exactly to the OEM specifications for your specific tractor model. (Installing it too deep can cause mechanical damage; too shallow will result in no signal). Tighten the lock nut to secure it.

7. 7

   Reconnect

   Plug the electrical connector back into the sensor.

8. 8

   Clear and Test

   Reconnect the battery, use a diagnostic tool to clear code 13.03.1A, and test the park lock engagement/disengagement to ensure the code does not return.