CLAAS Id764Dh / 764Dh (446) – TR2 (A57-2): The actual current measured on the solenoid valve SV2 return is less than the setpoint value.

The transmission control module is commanding a specific current (setpoint) to the SV2 solenoid valve (Y335-2), but the actual current returning to the module is lower than expected. This typically indicates an open circuit, high resistance in the wiring, or a failing solenoid coil.

• CLAAS Axion 800 Series (810, 820, 830, 840, 850)
• CLAAS Arion 400, 500, and 600 Series (410, 430, 510, 610, 630, 640)
• CLAAS Ares Series (Hexashift models)

1. 1

   Check for a possible open circuit in the solenoid valve supply harness

2. 2

   Check for a possible short circuit to earth (ground) on the solenoid valve wiring

3. 3

   Test the SV2 solenoid valve (Component Y335-2) for proper resistance and operation

4. 4

   Test the 'Auto 5' transmission module (TR2 / A57-2) using the official CLAAS diagnostic tool (Tool No. 60 05 033 249) to ensure the module itself is outputting the correct current

1. 1

   Locate the SV2 Solenoid

   Identify the 'Ratio under torque' / 'Gear under torque' solenoid valve SV2 (Y335-2) on the transmission valve block.

2. 2

   Inspect Wiring and Connectors

   Disconnect the harness at the SV2 solenoid and at the TR2 (A57-2) module. Inspect the pins for corrosion, moisture, or damage.

3. 3

   Perform Continuity and Ground Tests

   Use a multimeter to check the continuity of the wires between the TR2 module and the SV2 solenoid. Test the wires for a short to ground. Repair or replace the harness if an open or short circuit is found.

4. 4

   Test the Solenoid Valve

   Measure the resistance across the pins of the SV2 solenoid valve. If the resistance is out of specification (indicating an internal open or degraded coil), replace the solenoid valve.

5. 5

   Test the TR2 Module

   If the wiring and solenoid test perfectly, the fault likely lies within the TR2 (A57-2) 'Auto 5' module. Connect the CLAAS diagnostic tool (60 05 033 249) to verify module outputs. If the module is internally faulty and cannot regulate current, it must be replaced and reprogrammed.

6. 6

   Clear Codes

   After repairs, clear the fault codes and test drive the tractor in all Hexashift ranges to ensure the code does not return.