Massey Ferguson 04.00.71 – TRANS (Transmission Control Unit / Autotronic Controller): Cruise Speed C2 Button Issue (TRANS)

This fault code indicates an electrical malfunction or illogical signal coming from the "C2" cruise speed button. The system logs this code when the switch fails (e.g., gets stuck closed, fails open, or has a wiring short/break).

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5600 Series
• 5700 Series
• 6600 Series
• 6700 Series
• 7600 Series
• 7719S
• 8700 Series

1. 1

   Check the C2 button on the armrest or joystick for physical damage, sticking, or debris lodged around the micro-switch.

2. 2

   Inspect the electrical connector and wiring harness beneath the armrest console for looseness, chafing, or corrosion. Clean the contacts with an electrical contact cleaner.

3. 3

   Perform a continuity test on the C2 push button switch using a digital multimeter. It should show an open circuit (infinite resistance) when released, and a closed circuit (continuity) when pressed.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the negative battery terminal to prevent electrical shorts.

2. 2

   Access the Switch

   Carefully remove the retaining screws on the right-hand Command Control Armrest console or the multifunction joystick housing to expose the internal wiring and switches.

3. 3

   Disconnect

   Locate the C2 cruise speed button and unplug its electrical connector.

4. 4

   Remove

   Unclip or unscrew the faulty push button switch from its mounting seat in the plastic housing.

5. 5

   Install

   Snap or screw the new OEM push button switch into place and reconnect the electrical harness.

6. 6

   Reassemble

   Reinstall the armrest/joystick covers and secure all screws.

7. 7

   Test & Clear

   Reconnect the battery, turn the ignition on, and test the C2 button functionality. Clear the 04.00.71 fault code via the Datatronic screen or dealer diagnostic tool.