CLAAS Id762Dh / 762Dh (414) – TR2 (A57-2): Loss of the ENG module engine speed information (knowing the units are supplied with 12V after ignition and a theoretical speed of > 1 km/h is specified).

The transmission control module is no longer receiving the engine RPM/speed signal from the engine control module over the Powertrain CAN bus, despite the system having 12V power and the tractor moving at a theoretical speed greater than 1 km/h.

• Axion 800
• Axion 810
• Axion 820
• Axion 830
• Axion 840
• Axion 850
• Axion 920
• Axion 950
• Arion 410
• Arion 430
• Arion 510
• Arion 530
• Arion 550
• Arion 610
• Arion 620
• Arion 630
• Arion 640
• Ares 567 ATZ
• Ares 617 ATZ

1. 1

   Check the Powertrain CAN bus network for communication errors, shorts to ground, or shorts to 12V

2. 2

   Verify that the Engine Module ENG (A15) is receiving a steady 12V supply after the ignition is turned on

3. 3

   Check the adjustment, wiring, and resistance of the engine speed sensors (B231, B232, B228-1, B228-2)

1. 1

   Read Active Codes

   Connect the CLAAS Diagnostic System (CDS) or a compatible diagnostic tool (e.g., JCB ServiceMaster 4) to the Powertrain CAN bus to confirm active and stored fault codes.

2. 2

   Inspect Wiring

   Thoroughly inspect the wiring harnesses and connectors linking the ENG (A15) module to the TR2 (A57-2) module. Look for chafing, heat damage, or loose pins that could cause a loss of CAN communication when the tractor warms up.

3. 3

   Test Sensors

   Measure the output signals (Hz) and resistance of the B231, B232, B228-1, and B228-2 sensors while the engine is running. Replace any sensor that drops its signal as the engine block heats up.

4. 4

   Test the ENG (A15) Module

   If the wiring and sensors test good, the fault is likely internal to the ENG (A15) engine module (a common failure point when symptoms appear only after 5-10 minutes of running). Remove the module and have it bench-tested by an ECU specialist, or swap it with a known good unit if available.

5. 5

   Clear and Test

   After repairing the wiring, replacing the faulty sensor, or replacing the ENG (A15) module, clear the fault codes via the diagnostic tool and perform a test drive under load to ensure the code does not return.