John Deere 3514.04 – ECU: Sensor Supply #6 Voltage Out of Range Low

The Engine Control Unit (ECU) detects that the voltage on Sensor Supply Circuit #6 has dropped below the acceptable threshold. This is almost always caused by a short to ground in the wiring harness or an internally shorted sensor pulling the entire circuit's voltage down.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC
• 8245R through 8400R
• 8310RT
• 8335RT
• 8360RT
• 9470RT
• 9520RT
• 9570RT
• 7180
• 7280
• 7380
• 7480
• 7580
• 7780
• 7980

1. 1

   Isolate the sensors on Supply Circuit #6 by disconnecting them one at a time, starting with the DPF Differential Pressure Sensor and Exhaust Temperature sensors.

2. 2

   Monitor the voltage or active fault codes while disconnecting each sensor. If voltage returns to approximately 5V or the code changes to 'High' or 'Open', the unplugged sensor is internally shorted.

3. 3

   If all sensors are unplugged and the code remains, inspect the wiring harness routing near the DPF/exhaust area for melted insulation, chafing against the frame, or pinched wires.

4. 4

   Disconnect the main harness from the ECU and check for continuity to ground on the Sensor Supply 6 pin to confirm a harness short.

1. 1

   Turn off the machine and disconnect the battery ground before performing electrical repairs.

2. 2

   If a sensor is faulty: Remove the internally shorted sensor (e.g., DPF Pressure Sensor). Clean the connector face, apply dielectric grease, and install the replacement sensor.

3. 3

   If the harness is faulty: Locate the chafed or melted section of the wire. Cut out the damaged section and splice in a new wire using weather-sealed (heat-shrink) butt connectors, or replace the affected harness section.

4. 4

   Reconnect all components and restore battery power.

5. 5

   Clear Codes: Turn the key to the ON position and use a diagnostic tool (like John Deere Service ADVISOR) to clear the stored 003514.04 code.

6. 6

   Verify: Start the engine and allow it to reach operating temperature to ensure the code does not return and the aftertreatment sensors are reading correctly.