CLAAS Id77B6h / 77B6h (11) – HYD (A60) - Hydraulic Module: "Instruction" message of valve 2 is not received or is improbable

The system cannot verify the command being sent to or received from the valve, triggering a safety response where electrodistributor 2 is forced to return to its neutral position.

• Axion 800
• Axion 810
• Axion 820
• Axion 830
• Axion 840
• Axion 850
• Arion series

1. 1

   Check the Hydraulic CAN Bus Network for communication frame errors, open circuits, or short-circuits on the CAN bus lines

2. 2

   Check the connectors and the continuity of the harnesses linking the HYD (A60) module to the electrodistributor module

3. 3

   Check the sources of energy (fuses, power supply, and ground) for the electrodistributor module (VALVE power supply)

4. 4

   Check the electrodistributor module (A105-2) and the hydraulic module HYD (A60) for physical damage or internal faults

1. 1

   Document and Analyze

   Note all error codes present on the tractor. Analyze the interaction between them to ensure Id77B6h is the root anomaly and not a cascaded error from a broader CAN bus failure.

2. 2

   Inspect Harnesses

   Visually and electrically inspect the wiring harness between the HYD (A60) module and the Valve 2 electrodistributor (A105-2). Look for rubbed wires, pinched cables, or corroded pins.

3. 3

   Test the CAN Bus

   Using a multimeter or oscilloscope, verify the integrity of the Hydraulic CAN bus network. Ensure the resistance across the CAN lines is correct (typically 60 ohms with batteries disconnected) and that there are no shorts to ground or power.

4. 4

   Verify Power Supply

   Ensure the electrodistributor module is receiving the correct operating voltage.

5. 5

   Replace Faulty Component

   If the wiring, power, and CAN bus network are all intact, the fault lies within the electrodistributor module (A105-2) failing to process the instruction message, or the HYD (A60) module failing to send it. Replace the electrodistributor valve first as it is the most common point of failure.

6. 6

   Clear and Test

   Clear all error codes using the diagnostic tool, then operate the tractor's hydraulic functions to ensure the anomaly does not reappear.