Massey Ferguson 05.01.31 – Transmission Module (TRANS / TRANS1): Issue With Signal From 4wd Button On Side Pillar Dyna VT

The transmission controller is receiving an incorrect, out-of-range, or missing electrical signal from the manual 100% 4WD engagement switch (switch X137) located on the right-hand B-pillar. When this signal fails, the tractor's computer cannot verify the driver's manual input, and the system typically defaults to allowing only the '4-WD Auto mode' while disabling manual 100% 4WD override.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 7600 Series
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 8600 Series
• 8670
• 8690
• 8700 Series
• 8700 S Series
• 6S Series

1. 1

   Inspect the 4WD button on the right-hand B-pillar for physical damage, sticking, or debris preventing it from making contact.

2. 2

   Remove the switch and use a multimeter to test for continuity across the switch terminals when the button is pressed and released. If the switch does not close the circuit, it has failed internally.

3. 3

   Inspect the wiring harness connecting the B-pillar switch panel to the transmission controller (specifically looking at the roof harness/pillar harness junctions). Look for corroded pins, loose connectors, or chafed wires.

4. 4

   Check if code 05.01.32 ('Issue With Signal From Auto 4wd Button') is also present. If both the manual and auto 4WD buttons are throwing codes, the issue is likely a shared ground or a damaged wiring harness in the pillar rather than a single faulty switch.

1. 1

   Power Down

   Turn off the tractor ignition and disconnect the negative battery cable to prevent electrical shorts.

2. 2

   Access the Pillar Panel

   Carefully pry or unscrew the trim panel on the right-hand side B-pillar where the 4WD, PTO, and lighting controls are housed.

3. 3

   Disconnect the Switch

   Locate the back of the manual 4WD switch (X137) and unplug its electrical connector.

4. 4

   Remove the Faulty Switch

   Depress the retaining tabs on the sides of the switch body and push it out through the front of the pillar bezel.

5. 5

   Install the New Part

   Snap the replacement 4WD switch into the panel until it clicks securely into place.

6. 6

   Reconnect

   Plug the electrical harness back into the new switch.

7. 7

   Reassemble

   Reinstall the B-pillar trim panel and reconnect the battery.

8. 8

   Clear Codes

   Turn the ignition on, test the manual 4WD engagement, and clear the stored 05.01.31 fault code using a diagnostic tool or the tractor's onboard diagnostic menu.