CCU 523316.04 – CCU Switched Supply Voltage Low

CCU 523316.04 (CCU )

Code: 523316.04



This fault code indicates that the voltage supplied to the Chassis Control Unit (CCU) is below the normal operating threshold, specifically dropping below 9.0 volts. Low supply voltage can impair the functionality of the CCU, leading to potential issues in managing and controlling various vehicle systems.


The control unit degrades its functionality to prevent damage or incorrect operation due to insufficient voltage.


  • Inspect Battery and Charging System: Check the battery and alternator to ensure they are providing adequate power. Replace the battery if it is weak or not holding a charge.
  • Examine Wiring and Connections: Inspect all wiring and electrical connections for damage, corrosion, or looseness that could cause voltage drops. Repair or replace as necessary.
  • Test Voltage at CCU: Use a multimeter to measure the voltage at the CCU terminals to confirm low voltage conditions and identify where voltage drops occur.
  • Check for Parasitic Draws: Investigate any potential parasitic electrical draws that might be draining power from the system.
  • Reset and Recalibrate: After resolving the electrical issues, reset the CCU and recalibrate if needed to ensure proper operation.


Maintaining stable and adequate voltage supply to the CCU is crucial for the reliable operation of the vehicle’s control systems. Regular maintenance and monitoring of the electrical system can prevent such issues.

Control Units: John Deere

John Deere Parts
John Deere Logo