Case IH 3822 – Engine Control Unit (ECU) / EDC: Throttle Valve Actuator: Short circuit to battery on Out2 error for H-bridge

The Engine Control Unit (ECU) uses an internal power stage called an H-bridge to drive the motor of the Throttle Valve Actuator (TVA). This code is triggered when the ECU detects that the "Out2" circuit (specifically Pin A34 on the 60-pin engine connector) has a short circuit to a positive battery/external power source.

• Farmall
• Farmall 95U
• Farmall 105U
• Farmall 115U Pro EP
• Puma
• Magnum
• SV300

1. 1

   Verify if the fault code is currently active or stored as a historic code

2. 2

   Inspect the engine wiring harness between the Engine Controller (EDC) and the Throttle Valve Actuator (TVA) for chafed wires, melted insulation, or pinch points that could expose the wire to a positive battery source

3. 3

   Disconnect the 60-pin connector at the EDC and the connector at the TVA, then use a multimeter to test the Out2 circuit (Pin A34 on the EDC A-connector) for continuity to battery voltage

4. 4

   If the wiring harness shows no short to battery voltage, check if the short is internal to the Throttle Valve Actuator itself

1. 1

   Disconnect Power

   Ensure the machine is turned off and the battery is disconnected before performing electrical repairs.

2. 2

   Repair Wiring

   If your multimeter tests reveal a short to battery voltage in the wiring harness, locate the damaged section of the harness. Repair the damaged wires or replace the engine wiring harness entirely.

3. 3

   Replace the TVA

   If the wiring harness tests good (no short to battery), the fault is likely an internal short inside the Throttle Valve Actuator. Remove the intake tube, unbolt the TVA, and install a replacement unit.

4. 4

   Test the System

   Reconnect all harnesses, clear the fault codes using a diagnostic service tool, and run the engine to verify the repair.

5. 5

   Replace the EDC

   If the fault code persists after repairing the wiring and replacing the TVA, the Engine Controller's internal H-bridge power stage has failed. You will need to replace the EDC. Note: If the EDC is replaced, you must use the appropriate CNH service tool procedure to restore the engine's self-learning parameters.