CCU 002602.01 – Hydraulic Clean Oil Reservoir Level Very Low

CCU 002602.01 (CCU 2602.01)

Code: 002602.01

Shortcode: 2602.01


This fault code is triggered when the hydraulic oil level switch detects that the oil level in the clean oil reservoir is critically low, which could severely impact the hydraulic system’s performance and safety. The detection typically occurs under specific operating conditions where the hydraulic oil temperature is high, and the engine is running at a designated RPM. This issue often points to a significant depletion of oil in the differential case, which fails to supply adequate oil to the clean oil reservoir, possibly due to leaks or consumption through normal system operation.


The functionality of the hydraulic system is degraded to protect it from potential damage due to insufficient lubrication and cooling provided by the hydraulic oil.


  • Immediate Oil Level Check: Shut down the system and check the hydraulic oil level. Refill the clean oil reservoir to the recommended level to ensure proper operation.
  • Inspect for Leaks: Thoroughly inspect the hydraulic system for any signs of oil leaks, especially around the differential case and connections. Repair any leaks found to prevent future oil loss.
  • Monitor Oil Consumption: Regularly monitor oil levels and consumption rates to identify abnormal patterns that might indicate internal problems or leaks.
  • Evaluate System Temperature and Load Conditions: Analyze if the operating conditions such as high temperature and specific RPMs are contributing to faster oil depletion and adjust the operational parameters accordingly.
  • System Diagnostics and Resets: After addressing the issue, perform system diagnostics to check for any residual faults and reset the system to ensure all sensors and safety features are functioning correctly.


Maintaining optimal oil levels is critical for the health and efficiency of hydraulic systems. Regular checks and maintenance can prevent serious operational issues and extend the life of the machinery.

Control Units: John Deere

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