CLAAS Id7631h / 7631h (418) – TR2 (A57-2): Loss of gear upshift control information on the Powertrain CAN bus

Loss of gear upshift control information on the Powertrain CAN bus. When this fault is triggered, an audio warning sounds, and the system returns to the default start gear after shifting to transmission neutral. An "ISC" reset is not requested.

• CLAAS Arion 500/600 Series (510, 610, 630, 640)
• CLAAS Axion 800 Series (800, 810, 820, 830, 840, 850)

1. 1

   Check the sources of energy (fuses, power supply, and ground) for the affected modules

2. 2

   Check the connectors and continuity of the wiring harnesses linking the Drivestick, Armrest, and Transmission modules

3. 3

   Inspect both the Powertrain CAN bus network and the CLAAS vehicle CAN bus network for communication loss, short-circuits, or open circuits

4. 4

   Verify the Drivestick (R74) operation and signal output

5. 5

   Check the Armrest Module (A30 or A100) for proper communication

6. 6

   Verify communication of the Bridge Module (A103)

7. 7

   Check the 'Auto 5' Module using diagnostic tool n° 60 05 033 249

8. 8

   Check the compatibility of program versions, settings, and calibration

1. 1

   Read and Record Codes

   Note all error codes present on the tractor, as CAN bus faults often trigger multiple cascading codes. Identify if Id7631h is the root cause or a symptom of a broader CAN failure.

2. 2

   Inspect Wiring and Connectors

   Physically inspect the wiring harness from the Drivestick (R74) through the Armrest module (A30/A100) to the TR2 (A57-2) transmission module. Look for pinched wires, loose pins, or corrosion.

3. 3

   Test CAN Bus Continuity

   Use a multimeter to test the resistance and continuity of the Powertrain CAN bus and Vehicle CAN bus. Repair any open or shorted wires found.

4. 4

   Test/Replace Components

   If the wiring is intact, the fault likely lies within a module failing to send the upshift signal. Test the Drivestick (R74) and Armrest module (A30/A100). If the "Auto 5" module is suspect, test it with the specified CLAAS diagnostic tool (n° 60 05 033 249) and replace it if it fails.

5. 5

   Clear and Retest

   Clear all error codes from the system. Test drive the tractor, shifting through the gears to ensure the anomaly does not return.