Massey Ferguson 06.00.43 – TRANS1: Issue With Signal From External PTO On/Off Button Dyna VT (TRANS1)

The transmission control system is receiving an invalid, out-of-range, or missing electrical signal from the external Power Take-Off (PTO) control switch mounted on the rear fender/mudguard. This is typically caused by a failed switch mechanism (often due to water/dust ingress), a severed or chafed wire in the fender harness, or a corroded electrical connector.

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

1. 1

   Inspect the external fender PTO switch for physical damage, a torn rubber weather boot, or a stuck button mechanism.

2. 2

   Trace the wiring harness from the back of the fender switch to the main cab harness. Look for chafing, cuts from debris, or pinched wires against the mudguard frame.

3. 3

   Disconnect the switch and inspect the terminals for green corrosion, moisture, or pushed-out pins.

4. 4

   Using a multimeter, test the switch for continuity (normally closed, rated for 70V 0.5A 10W). Verify that the switch state changes cleanly when the button is pressed.

5. 5

   If a diagnostic scan tool is available, monitor the live data for the TRANS1 module to see if the external PTO switch state toggles when manually pressed.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical arcing or accidental PTO engagement during the repair.

2. 2

   Access the Switch

   Locate the faulty external PTO switch on the rear fender/mudguard. Depending on the exact fender extension kit, you may need to reach behind the mudguard panel or remove the retaining bezel on the front of the switch.

3. 3

   Disconnect

   Unplug the wiring harness connector from the back of the switch.

4. 4

   Remove and Replace

   Push the retaining tabs or remove the locking nut to extract the old switch. Insert the new switch into the fender mounting hole until it clicks or is securely fastened.

5. 5

   Reconnect

   Plug the wiring harness into the new switch, ensuring the weather-resistant sealing rubber is properly seated to prevent future moisture ingress.

6. 6

   Test and Clear

   Reconnect the battery. Turn the ignition on and test the external PTO engagement/disengagement (ensure all implements are clear and safety protocols are followed). Clear the 06.00.43 fault code using a diagnostic tool or the tractor's dash interface.