John Deere 3509.03 – ECU, CCU, PTR, or AIC: Sensor Supply 1 Voltage Out of Range High

The control module has detected that the 5-volt reference circuit is registering a voltage higher than the normal operating range (typically above 5.2 or 5.25 volts), usually caused by the 5V supply wire shorting to a higher voltage source or an internal failure of the module's voltage regulator.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5065M
• 5075M
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5095M
• 5095MH
• 5105M
• 5015ML
• 5090M
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 7185J
• 7195J
• 7205J
• 7210J
• 7225J
• 9470RT
• 9520RT
• 9570RT
• 670G
• 670GP
• 672G
• 672GP

1. 1

   Verify Voltage Output: Use a digital multimeter to test the sensor supply voltage circuitry at the affected sensors (e.g., fuel rail pressure sensor) to confirm if the voltage exceeds 5.25V.

2. 2

   Inspect Wiring and Connections: Thoroughly inspect the wiring harness for chafing, melted insulation, or pinched wires, looking specifically for areas where the 5V reference wire might be shorting against a 12V power wire.

3. 3

   Isolate the Sensors: Disconnect the sensors on the affected 5V circuit one at a time. If the voltage drops back to a normal 5.0V when a specific sensor is unplugged, that sensor is internally shorted.

4. 4

   Test the Control Module: If all sensors are disconnected and the wiring harness is completely isolated from 12V sources, but the module's output pin still reads >5.25V, the module's internal voltage regulator has failed.

1. 1

   Power Down

   Turn off the ignition and disconnect the negative battery cable to prevent accidental electrical damage during repairs.

2. 2

   Repair Wiring

   If a short to a 12V source was found in the harness, repair the damaged wire(s) using OEM-approved splicing techniques and heat-shrink tubing, or replace the affected harness section.

3. 3

   Replace Faulty Sensors

   If a sensor was found to be internally shorted during the isolation test, replace it.

4. 4

   Replace the Control Module

   If the diagnostic checks proved the control unit's internal voltage regulator is faulty, remove the defective module (ECU, CCU, etc.) and install a replacement. Note: A new control module will require programming/flashing with John Deere Service ADVISOR to match the machine's specifications.

5. 5

   Re-test System

   Reconnect the battery. Turn the key on and use a diagnostic tool to clear the 003509.03 fault code. Start the machine and monitor the sensor supply voltage to ensure it remains stable between 4.8V and 5.2V.