CSC 523666.04 – Low Supply Voltage at Rear Chassis Control Unit. John Deere System Advisory.

CSC 523666.04 (CSC )

Code: 523666.04



Error code CSC 523666.04 is generated when the supply voltage at the input of the rear chassis control unit falls below 9 V. Low voltage conditions can impair the operation of the control unit and associated systems, potentially leading to reduced performance or functionality.


The control software may limit or disable functionality to prevent operation under inadequate power conditions, which could cause further issues.


  • Check Power Supply and Connections: Inspect the power supply and all connections to the rear chassis control unit to ensure they are secure and free from damage or corrosion.
  • Measure Voltage Levels: Use diagnostic tools to measure the voltage at the input of the rear chassis control unit. Verify that it meets the required specifications.
  • Inspect and Repair Wiring Harness: Look for any issues in the wiring harness that might cause voltage drops, such as loose connections or damaged wires. Repair or replace faulty wiring as needed.
  • Evaluate Power Source: Ensure that the power source providing voltage to the rear chassis control unit is functioning correctly and providing stable voltage.
  • System Reset and Testing: After addressing the low voltage issue, reset the control system and perform comprehensive testing to confirm that the voltage levels are stable and the control unit operates correctly.


Maintaining stable power supply levels is critical for the reliable operation of control units. Regular checks of the power supply system and prompt repairs of any faults can help ensure consistent performance and prevent operational disruptions.

Control Units: John Deere

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