John Deere 3511.04 – Engine Control Unit (ECU): Sensor Supply 3 Circuit - Voltage Below Normal or Shorted to Low Source

The Engine Control Unit (ECU) provides a 5-volt reference signal to power various engine sensors on the #3 sensor supply circuit. This code triggers when the ECU detects that the voltage on this specific circuit has dropped below the acceptable specification (typically below 4.75V). This condition is almost always caused by a short to ground in the wiring harness or an internal short within one of the sensors sharing this 5V circuit (such as the Engine Oil Pressure Sensor, Fuel Pressure Sensor, or Throttle Position Sensors).

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 7R Series
• 8R Series
• 9RT Series
• 9470RT
• 9520RT
• 9570RT
• 9670 STS
• 9770 STS
• 7000 Series Forage Harvesters
• 8000 Series Forage Harvesters
• 770G Motor Grader
• 772G Motor Grader
• 130G Excavator
• 210G Excavator
• 550J Dozer
• 850J Dozer
• 7760 Cotton Picker

1. 1

   Turn the machine off and visually inspect the wiring harness and connectors associated with the 5-volt Sensor Supply 3 circuit for chafed wires rubbing against the engine block or chassis, corrosion, or loose pins.

2. 2

   Disconnect the sensors on this circuit one at a time (Engine Oil Pressure Sensor, Fuel Pressure Sensor, Air Throttle Position Sensor, Exhaust Throttle Position Sensor) to isolate a potential internal short.

3. 3

   Monitor the 5V supply voltage with a multimeter or John Deere Service ADVISOR while disconnecting each sensor. If the voltage jumps back up to 5V when a specific sensor is unplugged, that sensor has an internal short.

4. 4

   If all sensors are disconnected and the wiring harness tests good (no continuity to ground), but the 5V supply is still missing at the pins, check the ECU's internal voltage regulator.

1. 1

   Disconnect Power

   Disconnect the negative battery cable before performing electrical repairs.

2. 2

   Repair Wiring

   If the diagnostic checks revealed a chafed wire shorting to the frame, repair the damaged section using proper splicing techniques and heat-shrink tubing, or replace that section of the engine harness.

3. 3

   Replace Faulty Sensor

   If a sensor was identified as internally shorted during the isolation test, remove it. Clean the mounting port, install the new OEM sensor, and torque it to the manufacturer's specification.

4. 4

   Reconnect and Verify

   Reconnect all sensor harnesses, ensuring the connectors click securely into place and are free of moisture or debris.

5. 5

   Clear Codes

   Reconnect the battery, turn the key to the ON position, and use a diagnostic tool to clear the 003511.04 fault code.

6. 6

   Test Run

   Start the engine and verify that the code does not return and that the machine operates without derating.