New Holland ENG 394 – Engine Control Module (ECM): Front Timing current is too low

The Engine Control Module (ECM) has detected an open circuit, high resistance, or abnormally low current draw on the circuit that controls the front timing actuator (Timing Actuator #1).

• TG255
• TG285
• T8040
• MX240
• MX255
• MX270
• MX285
• STX 375

1. 1

   Inspect the engine wiring harness connecting the ECM to the front timing actuator on the CAPS pump for chafed wires, broken wires, or high resistance

2. 2

   Disconnect the CAPS pump harness connectors and the ECM connectors to inspect for corrosion, pushed-back pins, or moisture

3. 3

   Use a multimeter to check the resistance across the front timing actuator pins to verify if the solenoid itself has an internal open circuit

4. 4

   Inspect the main ground strap from the engine to the frame, ensuring the contact points are clean and tight

5. 5

   Verify that the ECM is outputting the correct boost voltage to the actuator circuit

1. 1

   Harness Repair

   If the diagnostic tests reveal a wiring issue at the pump connector, install a CAPS Pump Harness Repair Kit. Cut back the damaged wiring, splice in the new connector using proper crimps/solder, and seal the connections with heat shrink and dielectric grease.

2. 2

   Actuator / Pump Replacement

   If the wiring is intact but the front timing actuator has failed internally, replace the entire CAPS injection pump (or the accumulator module).

3. 3

   Bleed the Fuel System

   If the CAPS pump is replaced, loosen the fuel supply line at the CAPS pump, operate the lift pump (which runs for about 30 seconds upon key-on) until all air is expelled, and re-tighten.

4. 4

   Clear the Code

   Perform a key cycle, start the engine, and let it idle for 1 minute. The fault code should change to INACTIVE. Use an electronic service tool (like Cummins INSITE or CNH EST) to clear the inactive code from the ECM memory.