New Holland ENG 3824 – Engine Control Module (ECM / EDC / Engine ECU): Throttle Valve Actuator (TVA) Circuit - Short Circuit To Ground (A = 60pin Connector - Engine; A34)

The engine's control module has detected that the electrical circuit controlling the Throttle Valve Actuator (specifically the "Out2" circuit on Pin A34 of the H-bridge driver) is shorted directly to a ground source. This prevents the actuator from properly regulating the intake air/EGR flow.

• L220
• L316
• L318
• L320
• SR175
• SV185
• B90B
• B100B
• B95C
• B110C

1. 1

   Visually inspect the wiring harness running between the Engine ECM (60-pin connector) and the Throttle Valve Actuator (TVA) for chafed wires, melted insulation, or areas rubbing against the engine block or chassis.

2. 2

   Disconnect the TVA and the ECM. Inspect the pins (especially Pin A34 on the ECM side) for corrosion, moisture, or pushed-out pins.

3. 3

   With the battery disconnected and both the ECM and TVA unplugged, use a multimeter to check for continuity to ground on the wire corresponding to ECM Pin A34. If there is continuity to ground, the engine wiring harness is shorted. If there is no continuity to ground, the short circuit is likely internal to the Throttle Valve Actuator itself.

1. 1

   Disconnect the machine's battery to prevent electrical spikes.

   Disconnect the machine's battery to prevent electrical spikes.

2. 2

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

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

3. 3

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

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

4. 4

   Remove the intake tube connected to the TVA.

   Remove the intake tube connected to the TVA.

5. 5

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

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

6. 6

   Remove the faulty Throttle Valve Actuator and clean the mating surface.

   Remove the faulty Throttle Valve Actuator and clean the mating surface.

7. 7

   Install the new Throttle Valve Actuator and reconnect the intake tube.

   Install the new Throttle Valve Actuator and reconnect the intake tube.

8. 8

   Torque the mounting bolts and nuts to 20 - 30 N·m (15 - 22 lb ft).

   Torque the mounting bolts and nuts to 20 - 30 N·m (15 - 22 lb ft).

9. 9

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

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

10. 10

    Reconnect the battery, clear the fault codes using an electronic service tool, and run the engine to verify the repair.

    Reconnect the battery, clear the fault codes using an electronic service tool, and run the engine to verify the repair.