Case IH 19106 (F-3363-04) - ECU – Engine Control Module (ECM) / Aftertreatment System ECU: DEF/AdBlue tank heater actuator short circuit to ground failure

The control module has detected that the electrical circuit operating the DEF tank heater actuator has shorted to ground. This causes an unexpected voltage drop, disabling the DEF heating system and potentially triggering an engine derate or SCR inducement warning.

• VESTRUM CVX
• 240 Series Axial-Flow Combines (7240, 8240, 9240)
• T7 Series Tier 4B Tractors
• Farmall 40, 45, and 50 Tractors
• Case IH Skid Steer and Compact Track Loaders (SV340B, TR340, 410-450CT series)

1. 1

   Stop the engine and allow it to cool completely to avoid injury from hot engine coolant lines

2. 2

   Inspect the wiring harness and the connector leading to the DEF tank heater actuator for chafed wires, melted insulation, or pinched lines

3. 3

   Disconnect the actuator and inspect the pins for loose machine grounds, bent pins, corrosion, or water/debris intrusion

4. 4

   Using a digital multimeter, test the harness side for continuity to ground to determine if the wiring loom is shorted

5. 5

   Test the actuator pins directly to see if the solenoid coil itself has failed and shorted internally

1. 1

   Turn off the machine, remove the key, and disconnect the battery ground cable.

2. 2

   Locate the DEF tank heater actuator (coolant control valve).

   Typically located near the DEF tank or along the coolant lines routing to the tank.

3. 3

   Disconnect the electrical connector from the actuator.

4. 4

   Repair the damaged section of the wiring loom.

   If the diagnostic tests proved the wiring harness is at fault, use appropriate OEM repair connectors, terminals, and heat-shrink sleeving.

5. 5

   Clamp off the engine coolant hoses on both sides of the actuator valve.

   If the actuator itself is internally shorted, prepare to replace it and prevent coolant loss.

6. 6

   Loosen the hose clamps, remove the coolant lines from the actuator, and unbolt the actuator from its mounting bracket.

7. 7

   Install the new heater actuator valve, secure it to the bracket, and reconnect the coolant hoses.

   Remove the hose clamps.

8. 8

   Reconnect the electrical connector.

   Note: Some updated replacement valves may require a jumper/adapter harness if adapting from an older square 4-pin configuration to a newer 3-pin configuration.

9. 9

   Reconnect the battery ground.

10. 10

    Top off the engine coolant if any was lost.

11. 11

    Turn the key on, clear the fault codes using a diagnostic scan tool, and run the engine.

    Verify the code does not return and that there are no coolant leaks.