Case IH 3510-03 - DEC – Engine ECU (Engine Control Unit / EDC): 5 volt sensor supply instance 2 electrical circuit fault - voltage above normal

The 5-volt reference circuit (Supply #2) is shorted to a higher voltage source (such as a 12V battery circuit). When the Engine Control Unit detects voltage higher than the expected 5V on this circuit, it logs this code and will typically trigger an engine power derate to protect the system.

• MAGNUM AFS Connect
• Magnum series (e.g., Magnum 250, 310)
• Steiger series
• Puma series
• CVX series (e.g., CVX 140, 150, 160, 175, 195)
• Farmall series

1. 1

   Check Engine ECU connectors (pins J1-54/J1-18 for newer ECUs or J3-H4/J3-H3 for older ECUs) for corrosion, moisture, or bent pins.

2. 2

   Disconnect the VGT Vane Position sensor and Low-Pressure Fuel Pressure sensor one at a time. If voltage returns to 5V, the disconnected sensor is internally shorted.

3. 3

   Use a multimeter to check the wiring harness between the ECU and sensors for a short to battery voltage (12V) or chafed insulation rubbing against the engine block.

1. 1

   Power down machine

   Turn off the machine and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Inspect and clean connectors

   Disconnect the Engine ECU harness (J1 or J3 connectors). Clean the contacts with electrical contact cleaner and ensure no pins are pushed back or bridged by debris.

3. 3

   Repair wiring harness

   If multimeter testing revealed a short to a 12V source, locate the chafed or melted section. Splice and solder the damaged wires, then seal with heat-shrink tubing and protective loom.

4. 4

   Replace faulty sensor

   If diagnostic checks proved the VGT Vane Position sensor or Low-Pressure Fuel Pressure sensor was internally shorted, remove and replace the faulty sensor.

5. 5

   Reassemble and clear codes

   Reconnect all sensors, the ECU, and the battery. Use a compatible diagnostic scan tool to clear the inactive 3510-03 fault code.

6. 6

   Test run

   Start the engine and monitor the 5V sensor supply voltage via the diagnostic tool to ensure it remains stable and the code does not return.