John Deere 412 – Engine Control Unit (ECU): EGR Cooled Gas Temperature is High (ECU) / EGR Temperature Signal Extremely High.

This error code is triggered when the exhaust gas recirculation (EGR) exhaust temperature significantly exceeds the normal operating range. When this code is logged, the ECU typically initiates protective measures (engine derate), limiting engine speed and power to prevent damage due to overheating.

• 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
• 5095M
• 5105M
• 9230
• 9330
• 9430
• 9530
• 9630
• 9870 STS
• S660
• S670
• S760
• S770
• 7760
• 444K
• 544K
• 624K
• 724K
• 130G
• 210GLC

1. 1

   Inspect the EGR Cooler for internal clogging, fouling from deposits, or damage. Poor EGR cooling is a primary cause of this code.

2. 2

   Inspect the engine's general cooling system and radiator for debris that could be reducing overall cooling efficiency.

3. 3

   Check the EGR valve for proper operation, sticking, or carbon buildup.

4. 4

   Verify that there are no blockages or restrictions in the exhaust system that could cause excessive heat buildup.

5. 5

   Ensure the EGR temperature sensor is functioning correctly, not shorted, and providing accurate input voltage readings to the ECU.

1. 1

   Clean the EGR System

   Run a clean-out procedure on the EGR valves to remove carbon buildup.

2. 2

   Calibrate

   Perform a calibration reset on the EGR valves using a John Deere diagnostic tool (Service ADVISOR).

3. 3

   Test Run

   Run the machine under load to see if the code returns. If the code clears, the issue was likely carbon buildup.

4. 4

   Replace Faulty Components

   If the code persists, repair or replace the component identified during the diagnostic checks (e.g., replace a clogged EGR cooler, a sticking EGR valve, or a faulty EGR temperature sensor).

5. 5

   Clear Codes

   After repairs are made, reset the ECU to clear the fault code and perform a final system check to ensure exhaust gas temperatures return to normal specifications.