John Deere 4766.16 – ECU: DOC (Diesel Oxidation Catalyst) Outlet Temperature is Moderately High

DOC Outlet Temperature is Moderately High (or higher than expected). When this code is triggered, the system will disable Active Exhaust Filter cleaning. If the machine continues to operate under this condition, it will eventually result in engine power derating and a complete loss of machine availability.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5090M
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC
• 8235R
• 8245R
• 8260R
• 8285R
• 8310R
• 8310RT
• 8335R
• 8335RT
• 8360R
• 8360RT
• 8400R
• 9470RT
• 9520RT
• 9570RT
• D24x40 S3 Navigator HDD
• D40x55 S3 Navigator HDD

1. 1

   Inspect the Fuel System for issues that might cause excessively high exhaust temperatures, such as over-fueling or improper combustion

2. 2

   Verify Combustion Efficiency to ensure the engine is operating with the correct air-fuel ratio, checking for malfunctioning injectors or restricted air intake

3. 3

   Inspect the Exhaust System and DOC Condition for physical blockages, restrictions, or early wear

4. 4

   Review Operating Conditions to evaluate if the machine is being run under extreme loads or driving patterns that naturally elevate DOC temperatures

5. 5

   Verify the DOC outlet temperature sensor and its wiring harness for physical damage, melting, or electrical shorts

1. 1

   Cycle Power

   Turn the ignition key off and back on. In some cases, transient codes can be resolved by cycling the power or following the prompts on the CommandCenter™ display.

2. 2

   Perform Visual & Mechanical Inspections

   If the code persists, inspect the exhaust aftertreatment system for blockages and test the fuel injectors for over-fueling.

3. 3

   Replace the Sensor

   If the fuel and air systems are functioning properly and the DOC is not physically blocked, the DOC outlet temperature sensor is likely providing a false high reading. Remove and replace the sensor.

4. 4

   Reset the ECU

   After addressing the root cause or replacing the sensor, use a diagnostic tool to reset the ECU and clear the fault code.

5. 5

   Monitor the System

   Run the machine and monitor the live DOC outlet temperature data to ensure it returns to normal operating ranges and that active exhaust filter cleaning becomes available again.