CLAAS Id7633h / 7633h (420) – TR2 (A57-2) Transmission Module: Loss of the up and down shifting control of ranges on Powertrain CAN bus information

The transmission control system has lost communication with the shifting controls (specifically the upshift and downshift commands for the transmission ranges) over the Powertrain CAN bus network.

• CLAAS Axion 850–810
• CLAAS Axion 800 series
• CLAAS Arion 640–510
• CLAAS Arion 630–610 C

1. 1

   Check the physical shifting joystick (Drivestick R74) for proper operation and signal output

2. 2

   Check the Armrest Module (Cebis terminal module A30 or Multifunction Armrest module MFA A100)

3. 3

   Inspect the Powertrain CAN Bus Network wiring harness and connectors for continuity, shorts, or open circuits

4. 4

   Verify the integrity of the main CLAAS Vehicle CAN Bus Network

5. 5

   Check the Bridge Module (A103) that relays information between the CAN buses

6. 6

   Test the TR2 (A57-2) Auto 5 module using the official CLAAS diagnostic tool

1. 1

   Verify the Symptom

   Confirm that the tractor is unable to shift ranges up or down using the Drivestick. Note that an audio warning will sound when this fault occurs.

2. 2

   Inspect Wiring and Connections

   Visually and electrically test the Powertrain CAN bus and CLAAS Vehicle CAN bus wiring harnesses. Look for chafed wires or loose pins at the Drivestick (R74), Armrest module (A30/A100), Bridge module (A103), and TR2 module (A57-2).

3. 3

   Test the Drivestick and Armrest

   If the wiring is intact, test the Drivestick (R74) inputs. If the Drivestick is not sending signals to the Armrest module, replace the Drivestick. If the Armrest module is not broadcasting the Drivestick's commands to the CAN bus, the Armrest module (A30 or A100) may be at fault.

4. 4

   Test the Bridge Module

   Ensure the Bridge module (A103) is successfully relaying messages between the Vehicle CAN bus and the Powertrain CAN bus.

5. 5

   Diagnose the TR2 Module

   Connect the CLAAS diagnostic tool (Tool No. 60 05 033 249) to the TR2 (A57-2) "Auto 5" module. Run a module test. If the module fails to communicate or process the CAN bus shifting information, replace the TR2 (A57-2) module.

6. 6

   Clear Codes and Test

   After replacing the faulty component or repairing the wiring, clear the fault codes and test drive the tractor to ensure upshifting and downshifting of ranges operates normally.