ECU 004766.16 – DOC Outlet Temperature Moderately High. John Deere System Advisory.

ECU 004766.16 (ECU 4766.16)

Code: 004766.16

Shortcode: 4766.16


This diagnostic code is set when the DOC outlet temperature is detected to be moderately high. Moderately elevated outlet temperatures can indicate more significant issues within the exhaust system or engine operation that need attention.


The ECU may limit or adjust engine performance to manage the moderately high DOC outlet temperature, ensuring safe operation of the exhaust system and emissions control.


  • Inspect Fuel System: Check for issues in the fuel injection system that might cause moderately higher exhaust temperatures, such as excessive fuel injection or improper combustion.
  • Verify Combustion Efficiency: Ensure that the engine combustion process is operating efficiently. Address any issues related to incorrect air-fuel ratios or malfunctioning injectors.
  • Inspect Exhaust System: Look for blockages or restrictions in the exhaust system that could contribute to elevated temperatures.
  • Check DOC Condition: Inspect the DOC for any signs of wear, damage, or blockages that might cause higher outlet temperatures.
  • Monitor Operating Conditions: Review the operating conditions and driving patterns that might contribute to moderately elevated DOC outlet temperatures.
  • Reset ECU and Monitor System: After addressing the issue, reset the ECU to clear the fault code and monitor the system to ensure temperatures return to normal ranges.


Maintaining appropriate DOC outlet temperatures is essential for the efficiency and longevity of the exhaust aftertreatment system. Regular inspections and maintenance can help prevent temperature-related issues.

Control Units: John Deere

John Deere Parts
John Deere Logo