New Holland ENG 3419 – ENGINE: ECU Power stages: SCG error on the Turbocharger PWM output power stage

The Engine Control Unit (ECU) has detected a Short Circuit to Ground (SCG) in the Pulse Width Modulation (PWM) output circuit that controls the turbocharger wastegate actuator (electric valve).

• W50C
• W60C
• W70C
• W80C
• 21F
• 121F
• 221F
• 321F
• T5.95
• T5.105
• T5.115
• T6
• T7
• T8
• T9
• L218
• L220
• C227

1. 1

   Connect the Electronic Service Tool (EST) to the diagnostic connector to verify that fault code 3419 is currently active.

2. 2

   Visually inspect the wiring harness running from the Engine ECU to the turbocharger wastegate actuator for chafing, melting, or pinched wires that could cause a short to ground.

3. 3

   Disconnect the turbocharger actuator and the ECU connector. Measure the resistance between the turbocharger PWM signal wire and the chassis ground. If there is continuity, the harness is shorted.

4. 4

   Check the electric wastegate valve for internal short circuits.

1. 1

   Repair/Replace Wiring

   If the multimeter test reveals a short to ground in the wiring harness, locate the damaged section of the wire. Repair the wire using OEM-approved splicing methods and heat shrink, or replace the affected engine harness section.

2. 2

   Replace the Actuator

   If the wiring harness tests good (no short to ground), the short is likely internal to the turbocharger wastegate actuator. Replace the electric valve/actuator. (Note: On some turbocharger models, the actuator is not serviced separately and the entire turbocharger assembly must be replaced).

3. 3

   Test the ECU

   If both the wiring harness and the actuator test perfectly fine, the fault lies within the Engine ECU's internal power stage. The ECU will need to be replaced and reprogrammed by a dealer.

4. 4

   Clear Codes

   Reconnect all components, turn the key on, and use the Electronic Service Tool to clear the fault codes. Run the engine to verify the code does not return.