Case IH F-100-21 - ECU – ECU: Oil pressure is too low

The engine oil pressure has dropped below the minimum safe operating threshold programmed into the control module. Operating the machine in this condition can lead to severe internal engine damage.

• MAGNUM AFS Connect
• Magnum 340
• Magnum 400 AFS Connect
• Magnum 370
• Magnum 380

1. 1

   Check the engine oil level using the dipstick to ensure it is within the safe operating range.

2. 2

   Inspect the engine block, oil filter housing, and oil pan for visible leaks.

3. 3

   Inspect the oil pressure sensor wiring harness and connector for oxidation, damage, or loose pins.

4. 4

   Verify that the oil pressure sensor is receiving the correct +5V reference supply voltage from the ECU.

5. 5

   Connect a mechanical oil pressure gauge to the engine block to verify the actual oil pressure and rule out a failing sensor.

1. 1

   Correct Fluid Levels

   If the oil level is low, top up with the OEM-specified engine oil to the correct level and retest the machine.

2. 2

   Sensor Replacement

   If the mechanical gauge shows normal oil pressure but the ECU still logs the F-100-21 code, the engine oil pressure sensor is faulty and must be replaced.

3. 3

   Investigate Mechanical Failures

   If the mechanical gauge confirms that the oil pressure is actually low, do not run the engine. Investigate mechanical causes such as a clogged oil filter, blocked oil pickup tube, failing oil pump, or worn engine bearings.

4. 4

   Routine Maintenance

   Replace the engine oil and filter if they are heavily contaminated or past their service interval.

5. 5

   Clear Codes

   Clear the active and logged fault codes using a diagnostic service tool and run the engine to verify the repair.