Massey Ferguson 04.00.94 – TRANS: CAN BUS Comm Issue Transmission to Armrest

The data link (Tractor Data Bus or CAN BUS) connecting the armrest controller to the transmission controller has been interrupted, corrupted, or lost. This prevents communication between the modules, typically caused by a power/ground issue, wiring fault, or controller failure.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5709
• 5710
• 5711
• 5712
• 5713
• 6712S
• 6713S
• 6714S
• 6715S
• 6716S
• 6718S
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7714S
• 7719S

1. 1

   Check controller functionality by verifying that both the transmission controller and the armrest controller are powering up (check instrument panel display and backlight)

2. 2

   Check for accompanying fault codes or symptoms that might indicate a total transmission controller failure

3. 3

   Inspect connector C137 at the armrest controller to ensure it is correctly installed, fully seated, and free of pushed pins or corrosion

4. 4

   Test the CAN BUS / Tractor Data Bus (TDB) wiring harness between the transmission controller and the armrest module for chafing, breaks, or short circuits

5. 5

   Verify power and ground supply circuits to the armrest controller, as a voltage drop can cause the module to drop off the CAN network

1. 1

   Power down

   Turn off the tractor and disconnect the battery to prevent electrical spikes during the repair.

2. 2

   Access the wiring

   Remove the necessary interior cab trim to access the wiring harness connecting the armrest module to the main cab harness.

3. 3

   Clean and re-seat connections

   Disconnect connector C137 and any intermediate CAN BUS connectors. Spray with electrical contact cleaner, allow to dry, and apply dielectric grease. Reconnect and ensure the locking tabs click into place.

4. 4

   Repair harness

   If continuity testing reveals a break in the CAN High or CAN Low wires, repair the wiring harness using OEM-approved splicing methods.

5. 5

   Replace the module

   If the wiring, power, and grounds are all intact but the armrest controller is still not communicating on the bus, replace the internally failed armrest controller or joystick module.

6. 6

   Clear codes and calibrate

   Reconnect the battery, turn the key to the ON position, and use an AGCO Electronic Diagnostic Tool (EDT) to clear the 04.00.94 fault code. Recalibrate the armrest lever/joystick after installing a new module.