New Holland ENG 3825 – Engine Control Module (ECM): Throttle Valve Actuator (TVA) Circuit - Short circuit over load error for H-bridge.

The Engine Control Module (ECM) uses an internal "H-bridge" circuit to reverse the polarity and drive the Throttle Valve Actuator motor open and closed. This fault code triggers when the ECM detects that the H-bridge circuit is drawing excessive current (an overload/short circuit). This is typically caused by a short in the wiring harness, an internal electrical short within the TVA motor itself, or a physically jammed throttle valve that causes the motor to stall and pull high current.

• L218
• L220
• C227
• C232
• C238
• T5.95
• T5.105
• T5.115
• TD5.115
• Workmaster 50

1. 1

   Turn off the ignition switch and disconnect the battery.

2. 2

   Disconnect the electrical connector at the Throttle Valve Actuator (TVA) and the 60-pin connector at the Engine ECU. Inspect both connectors for damaged, corroded, or backed-out pins.

3. 3

   Using a multimeter, check the wiring harness between the ECU and the TVA connector for continuity. Specifically, check the H-bridge output pins on the ECU (identified in F5C manuals as pins A34 and A49).

4. 4

   Test the TVA harness circuits for a short to ground or a short to battery.

5. 5

   If the wiring harness tests good, remove the TVA and inspect the butterfly valve. Heavy carbon or soot buildup from the EGR system can cause the valve to jam mechanically, which overloads the actuator motor.

6. 6

   If the valve moves freely and the wiring is intact, the internal electrical motor of the TVA is shorted and the actuator must be replaced.

1. 1

   Turn off the machine and disconnect the battery negative cable.

2. 2

   Locate the Throttle Valve Actuator (TVA) on the engine intake manifold.

3. 3

   Disconnect the electrical connections to the TVA and the nearby air pressure/temperature sensor.

4. 4

   Loosen the clamps and remove the air intake tube connected to the TVA.

5. 5

   Remove the mounting bolts and nuts securing the TVA to the intake manifold.

6. 6

   Remove the old TVA and clean the mating surface on the intake manifold to ensure a good seal.

7. 7

   Install the new Throttle Valve Actuator.

8. 8

   Tighten the TVA mounting bolts/nuts.

   Torque Specification: 20 - 30 N·m (15 - 22 lb ft).

9. 9

   Reinstall the air intake tube and tighten the clamps.

10. 10

    Reconnect the electrical connections to the TVA and sensors.

11. 11

    Reconnect the battery, turn on the ignition, and use a diagnostic tool to clear the fault codes. Run the engine to confirm the repair.