Massey Ferguson 3.03.19 – MFA (Multifunction Armrest) module: CAN Bus Message From Joystick Controls On Arm Rest (MFA)

Communication failure on the CAN bus indicating the main control system is not receiving the expected data messages from the joystick controls located on the armrest. This may cause the tractor to lock out hydraulic functions, spool valves, or transmission commands for safety reasons.

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 5600 Series
• 5611
• 5612
• 5613
• 5700 S / SL Series
• 5710
• 5711S
• 5713S
• 6600 & 6700 S Series
• 6615
• 6718S
• 7600 & 7700 S Series
• 7615
• 7620
• 7718
• 7726
• 8700 S Series
• 8727S
• 8730S
• 8740S

1. 1

   Inspect the wiring harness routing from the base of the armrest to the main cab harness for pinch points, chafing, or broken wires caused by armrest or seat movement.

2. 2

   Disconnect the plugs at the base of the joystick and the MFA circuit board to check for bent pins, pushed-out terminals, or corrosion.

3. 3

   Verify that the MFA module is receiving its required 10V/12V reference supply and has a solid ground, as a voltage drop can cause the CAN transceiver to drop offline.

4. 4

   Connect a compatible diagnostic scanner (such as AGCO EDT or Jaltest) to read live data. If the MFA is online but the joystick state shows 'Error' or 'Not Available', the fault is isolated to the joystick itself.

1. 1

   Power Down

   Turn off the tractor and disconnect the negative battery terminal to prevent electrical spikes during module handling.

2. 2

   Access the MFA

   Remove the plastic housing/covers on the Multifunction Armrest to expose the internal wiring, the joystick base, and the MFA printed circuit board (PCB).

3. 3

   Repair Wiring

   If the diagnostic checks revealed a broken CAN High or CAN Low wire in the armrest pivot point, repair the wire using proper soldering and heat-shrink tubing.

4. 4

   Replace the Component

   If the wiring is intact, the internal CAN transceiver in the joystick or the MFA controller has failed. Disconnect the faulty joystick element or MFA PCB and swap in the OEM replacement.

5. 5

   Reassembly

   Secure the new component, route the wiring carefully to avoid future pinching, and reinstall the armrest covers. Reconnect the battery.

6. 6

   Calibration / EOL Programming

   Using the AGCO EDT (Electronic Diagnostic Tool), clear the inactive fault codes. You must then perform a Joystick Calibration and/or EOL (End of Line) programming so the TECU recognizes the new joystick's neutral and maximum travel positions.