Case IH 19637 – Engine Control Module (ECM / EDC): Fuel Filter Clog Switch blocked in clogged status

The system detects that the fuel filter clogging switch is defective and blocked in the active (closed/clogged) position, even when the filter is not restricted.

• Tier 4b
• Case IH 9250 Combines
• Magnums
• Steigers

1. 1

   Locate the fuel filter clog switch on the fuel filter housing head.

2. 2

   Visually inspect the switch pins and the wiring harness for damage or corrosion.

3. 3

   Check continuity between the ECU connector pins and the switch pins to rule out a wiring short.

1. 1

   Turn off the machine and disconnect the battery.

   Turn off the machine and disconnect the battery.

2. 2

   Disconnect the wiring harness.

   Disconnect the wiring harness from the fuel filter clog switch.

3. 3

   Test the switch.

   Test the switch for an internal short using a multimeter.

4. 4

   Evaluate switch failure.

   If the wiring harness has good continuity but the switch remains closed (active) regardless of filter condition, the switch is internally failed.

5. 5

   Replace the switch.

   Remove and replace the defective fuel filter clog switch.

6. 6

   Reconnect and clear codes.

   Reconnect the harness, restore power, and clear the fault codes.