Case IH 3822 – Engine Control Unit (ECU): Throttle Valve Actuator (TVA) Circuit - Short Circuit To Battery (A = 60pin Connector - Engine; A34) / Short circuit to battery on Out2 error for H-bridge.

The engine control module has detected that the circuit controlling the Throttle Valve Actuator (specifically the Out2 circuit located at Pin A34 of the 60-pin engine connector) is receiving unintended battery voltage. This indicates a short to power in the wiring harness or an internal short within the actuator's H-bridge/solenoid.

• skid steer
• Farmall 95U Pro EP
• Farmall 105U Pro EP
• Farmall 115U Pro EP
• Maxxum 135
• Maxxum 145
• Maxxum 150
• SV300
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)

1. 1

   Visually inspect the wiring harness running from the Engine ECU to the Throttle Valve Actuator for chafing, melted insulation, or pinched wires that could expose the wire to a battery power source.

2. 2

   Disconnect the 60-pin connector at the Engine ECU and the connector at the TVA. Inspect Pin A34 on the ECU side for corrosion, moisture, or bent pins.

3. 3

   With the ECU and TVA disconnected, use a multimeter to test the wire corresponding to Pin A34 for continuity to battery voltage. If voltage is present, the harness is shorted to power.

4. 4

   If the wiring harness tests good (no short to battery), the short is likely internal to the Throttle Valve Actuator's H-bridge circuit.

1. 1

   Turn off the machine's ignition and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Locate the Engine ECU and carefully disconnect the 60-pin engine harness connector.

3. 3

   Locate the Throttle Valve Actuator on the engine intake and disconnect its electrical pigtail.

4. 4

   Perform the multimeter tests outlined in the diagnostic steps.

5. 5

   If the harness is faulty: Trace the wire from Pin A34 to the TVA. Locate the shorted section of the wire and repair it using proper soldering and heat-shrink techniques, or replace the affected engine harness section.

6. 6

   If the TVA is faulty: Unbolt the Throttle Valve Actuator from the intake manifold assembly. Clean the mating surface, install a new gasket/seal, and bolt the new TVA into place.

7. 7

   Reconnect the TVA electrical connector and the 60-pin ECU connector.

8. 8

   Reconnect the battery, turn the key on, and use a diagnostic service tool to clear the inactive 3822 fault code. Run the engine to verify the code does not return and that the engine idles correctly.