Case IH 17643 (F-3285-05) - ECU – Engine Control Unit (ECU / EDC): Differential pressure sensor: sensor reporting under voltage error

The sensor monitoring the pressure difference across the Diesel Particulate Filter (DPF) or exhaust system is receiving insufficient voltage, or the sensor itself has suffered an internal electrical failure.

• VESTRUM CVX
• Austoft 9900 Sugarcane Harvesters
• Farmall 40
• Farmall 45
• Farmall 50
• Farmall 115U
• SR/SV series skid steers
• Magnum
• Steiger

1. 1

   Check the electrical harness and connector at the DPF differential pressure sensor for corrosion, pushed-out pins, or moisture

2. 2

   Test the sensor connector for proper reference voltage and ground to identify a short to ground or broken supply wire

3. 3

   Inspect the physical hoses connecting the sensor to the DPF/exhaust to ensure they are not detached, melted, or blocked with soot

4. 4

   Verify the main power and ground connections to the Engine ECU, as systemic low voltage can trigger this code

1. 1

   Locate the Sensor

   Find the DPF differential pressure sensor, typically mounted near the exhaust/DPF assembly with two small hoses routed to it.

2. 2

   Disconnect and Inspect

   Unplug the sensor's electrical connector. Clean the contacts with electrical contact cleaner if dirt or corrosion is present.

3. 3

   Repair Wiring

   If the voltage test reveals a drop or missing reference voltage, trace the harness back to the ECU and repair any chafed or broken wires.

4. 4

   Replace the Sensor

   If the wiring harness tests perfectly (proper voltage and continuity to the ECU) and the hoses are clear, the sensor has suffered an internal failure. Remove the hose clamps, unbolt the sensor bracket, and install a new differential pressure sensor.

5. 5

   Clear Codes

   Reconnect the battery/power, use a diagnostic tool to clear the 17643 (F-3285-05) fault code from the Engine ECU, and run the engine to verify the code does not return.