CLAAS Id7640h / 7640h (433) – TR2 (A57-2) / Transmission Control Module 2: Calibration of the Power Boost failed, Power Boost only in C and D

The system is receiving a "Bad measurement" because Engine speed sensor 1 of 2 is disconnected or failing. Because the system cannot accurately read the engine speed from this sensor, the Power Boost calibration fails and its functionality is restricted.

• CLAAS Arion series (Arion 640-510)
• CLAAS Axion series (Axion 850-810)

1. 1

   Inspect engine speed sensor connections, including the wiring harness, connector plug, and pins for corrosion, backed-out pins, or physical breaks

2. 2

   Test the inductive engine speed sensor resistance (expected ~1050 ± 100 Ohms) and signal output (expected 250Hz signal)

3. 3

   Check for related active code Id7641h (434), which indicates the sensor is disconnected during operation

1. 1

   Resolve the Circuit Interruption

   Reconnect the unplugged sensor harness, repair any broken wiring, or replace the engine speed sensor if it has failed internally.

2. 2

   Clear Active Faults

   The tractor will automatically return to normal mode once the physical sensor fault disappears.

3. 3

   Recalibrate

   Run the Power Boost calibration procedure via the CEBIS terminal or METADIAG© diagnostic tool so the transmission module can relearn the parameters.