John Deere 412.03 – ECU: EGR Cooled Gas Temperature Signal Voltage is High (ECU) / EGR Temperature Sensor Input Voltage Problem

The Engine Control Unit has detected that the voltage signal from the Exhaust Gas Recirculation (EGR) temperature sensor is higher than the normal operating range. This typically indicates an open circuit in the sensor harness (either the signal or ground wire) or an internal failure of the EGR temperature sensor itself.

• 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
• 7200R
• 7230R
• 8235R
• 8360R
• 9230
• 9330
• 9430
• 9530
• 9630
• 9470RT
• 9520RT
• 9570RT
• 204L
• 304L
• 444K
• 524K
• 624K
• 724K
• 724L
• 9760STS
• S660
• S670
• S770
• 250D
• 210GLC
• 350GLC
• 643L
• 843L

1. 1

   Inspect the EGR temperature sensor wiring harness for visible damage, chafing, or disconnected plugs

2. 2

   Disconnect the EGR temperature sensor and inspect the pins for corrosion, moisture, or bent terminals

3. 3

   Test the harness for an open circuit on both the signal and ground wires leading back to the ECU

4. 4

   Test the EGR temperature sensor's resistance with a multimeter to determine if the sensor itself has failed internally (creating an open circuit)

1. 1

   Turn off the engine, remove the key, and disconnect the battery to ensure electrical safety.

   Ensure electrical safety before beginning work.

2. 2

   Locate the EGR temperature sensor, which is threaded into the exhaust gas recirculation system/cooler piping.

   Identify the sensor location on the exhaust piping.

3. 3

   Disconnect the electrical harness connector from the sensor.

   Unplug the sensor from the wiring harness.

4. 4

   If the diagnostic tests revealed a wiring issue, repair the broken wire or replace the damaged harness section.

   Address any open circuits or damage found in the harness.

5. 5

   If the sensor is faulty, use a wrench to carefully unscrew the old EGR temperature sensor from the exhaust piping.

   Remove the failed sensor.

6. 6

   Thread the new EGR temperature sensor into place and tighten to OEM torque specifications.

   Install the replacement sensor securely.

7. 7

   Reconnect the electrical harness to the new sensor.

   Restore the electrical connection.

8. 8

   Reconnect the battery.

   Restore power to the machine.

9. 9

   Clear the fault codes from the ECU using John Deere Service ADVISOR (or a compatible diagnostic scanner) and run the engine to verify the code does not return.

   Verify the repair was successful.