Case IH 3361 – Engine Control Unit (ECU) / Aftertreatment Control Module OR Engine Control Module (ECM): DEF Dosing Fault / DEF Injection Valve Actuator Error OR ECM EEPROM - General Error

On Tier 4 Final models, the DEF dosing valve is not delivering the correct amount of fluid, or there is an electrical fault on the valve's circuit. On Tier 3 / Tier 4a models, there is a read/write operation failure or a general memory fault within the Engine Control Module's internal EEPROM memory.

• skid steer
• Case IH Magnum (235–340 Series 4)
• Case IH Steiger
• Case IH Puma
• Case IH Maxxum
• Case IH Optum
• Case 580N
• Case 580 Super N
• SSL/CTL skid steers

1. 1

   For Tier 4 Final (DEF Fault): Inspect the wiring harness leading to the DEF dosing valve for chafing, open circuits, or short circuits to ground.

2. 2

   For Tier 4 Final (DEF Fault): Inspect the DEF dosing lines for crystallized DEF, which is common after extended sitting and blocks fluid delivery.

3. 3

   For Tier 4 Final (DEF Fault): Check the DEF filter for heavy blockages that restrict fluid flow to the dosing valve.

4. 4

   For Tier 4 Final (DEF Fault): Verify that the DEF pump module is generating the correct system pressure.

5. 5

   For Tier 3 / Tier 4a (EEPROM Error): Check battery voltage and ECM harness grounds, as low voltage or poor connections can cause memory read/write errors.

6. 6

   For Tier 3 / Tier 4a (EEPROM Error): Power cycle the system by turning the ignition off, waiting for the ECU to power down completely, and restarting the machine.

1. 1

   Disconnect battery

   For DEF Dosing System: Disconnect the battery to ensure safety while working on the electrical harness.

2. 2

   Inspect and test connector

   For DEF Dosing System: Visually inspect and test the DEF dosing valve connector with a multimeter. Repair any damaged pins or wires.

3. 3

   Flush DEF lines

   For DEF Dosing System: Remove the DEF dosing lines. If crystallized urea is present, flush the lines with warm distilled water to dissolve the blockage.

4. 4

   Replace DEF filter

   For DEF Dosing System: Replace the DEF filter located in the DEF pump module, as this should be done at regular service intervals anyway.

5. 5

   Replace DEF dosing valve

   For DEF Dosing System: If the wiring is intact, the lines are clear, and the filter is new, the DEF dosing valve (injector) has failed mechanically or electrically and must be replaced.

6. 6

   Clear codes and test

   For DEF Dosing System: Reconnect the battery, clear the fault codes using a CNH Electronic Service Tool (EST), and run a forced DEF dosing test to verify the repair.

7. 7

   Clean ECM connections

   For ECM EEPROM Error: Clean and tighten all ECM power and ground connections.

8. 8

   Check for software update

   For ECM EEPROM Error: Have a dealer check if an ECU software update/flash is available to resolve the memory glitch.

9. 9

   Replace Engine ECM

   For ECM EEPROM Error: If the code persists and the ECM cannot retain its memory, the Engine ECM must be replaced and reprogrammed by an authorized dealer.