Case IH 55022 – STEERING Control Module (Steering ECU): ARTIC_BYPASS Driver Pin Voltage Not Detected

The control module is not detecting the expected voltage on the ARTIC_BYPASS (Articulation Bypass) driver pin (Pin C057-10). This is an electrical fault, most commonly caused by an open circuit, a short to ground, a disconnected harness plug, or a burned-out articulation bypass valve solenoid coil.

• STX Steiger
• Case IH STX Series (STX-275, STX-325, STX-440)
• Case IH Steiger Series (280, 330, 335, 350, 400, 450, 500, 550, 600, and Quadtrac variants)

1. 1

   Visual Inspection: Trace the wiring harness from the Steering ECU down to the articulation bypass valve solenoid on the steering valve block. Look for pinched wires, chafing against the articulated joint, or rodent damage.

2. 2

   Connector Inspection: Disconnect the harness at the articulation bypass solenoid and at the Steering ECU (specifically checking the connector containing Pin C057-10). Inspect for pushed-back pins, corrosion, or moisture intrusion.

3. 3

   Solenoid Resistance Test: Using a multimeter, measure the resistance across the pins of the articulation bypass solenoid coil. An infinite reading (OL) indicates an open coil that has failed. A reading of 0 ohms indicates a dead short.

4. 4

   Harness Continuity Test: Measure the continuity of the signal wire between ECU Pin C057-10 and the solenoid connector. Test the same wire for a short to ground.

5. 5

   ECU Output Test: With the key ON and the system active, back-probe Pin C057-10 at the ECU to verify if the controller is outputting the required voltage. If the wire and solenoid are good but no voltage is present, the Steering ECU may have suffered an internal driver failure.

1. 1

   Secure the Machine

   Park the tractor on a level surface, articulate the tractor to the straight-ahead position, and install the mechanical articulation lock frame to prevent accidental movement or crushing hazards.

2. 2

   Disconnect Power

   Turn off the ignition and disconnect the negative battery cable.

3. 3

   Locate the Component

   Locate the articulation bypass valve, which is typically mounted on the main steering control valve block near the articulation joint.

4. 4

   Remove the Faulty Component

   Disconnect the electrical connector to the bypass solenoid. If diagnostic tests proved the solenoid is faulty, remove the retaining nut holding the solenoid coil to the valve stem and slide the old coil off.

5. 5

   Install the New Part

   Slide the new articulation bypass solenoid coil onto the valve stem and tighten the retaining nut to the manufacturer's specified torque (do not overtighten, as this can distort the valve spool).

6. 6

   Repair Wiring (If Applicable)

   If the wiring harness was the culprit, splice in a new connector pigtail or repair the broken wire using weather-sealed, heat-shrink butt connectors.

7. 7

   Reassemble

   Reconnect the electrical plug to the solenoid.

8. 8

   Restore Power

   Reconnect the battery, remove the articulation lock, and turn the ignition ON.

9. 9

   Clear Codes

   Clear the stored 55022 fault code using the tractor's in-cab diagnostic display or a CNH Electronic Service Tool (EST).

10. 10

    Test

    Start the engine and test the steering system lock-to-lock to ensure the code does not return and the articulation bypass functions correctly.