Case IH 29 – Instrumentation Controller (INST) or Central Controller (XCM): Hydraulic Control Valve Disconnected

Indicates that there is an open circuit in the chassis harness or a complete loss of communication between the tractor's instrumentation and the remote hydraulic controller.

• MXM
• Magnum Series (MX210, MX230, MX255, MX285, and Series 4 235-340)
• Puma Series (165, 170, 180, 185, 195, 210, 215, 220, 225, 230)
• MXM Series (MXM 120 through MXM 190)
• Maxxum Series
• Steiger Series

1. 1

   Verify the communication lines between the instrument controller and the remote hydraulic controller

2. 2

   Ensure that connector C055 (the primary connection for the remote hydraulic controller) is securely plugged in and free of corrosion

3. 3

   Test the chassis harness for open circuits, specifically checking the signal ground

4. 4

   Verify that the Remote Hydraulic Controller is receiving proper voltage and check for over-voltage faults (like AUX 8012) which can shut down the controller

1. 1

   Visual Inspection

   Locate the remote hydraulic control valves and the chassis harness. Inspect the wiring for physical damage, rubbing, or disconnected plugs.

2. 2

   Clean and Reconnect

   If connector C055 or the valve solenoids are disconnected or corroded, clean the pins with electrical contact cleaner, apply dielectric grease, and securely reconnect them.

3. 3

   Harness Repair

   If a multimeter continuity test reveals an open circuit in the chassis harness or signal ground, repair the broken wire or replace the affected harness section.

4. 4

   Component Replacement

   If the wiring is intact and the data bus is communicating properly, but the fault persists, the internal circuitry of the hydraulic control valve or the Remote Hydraulic Controller itself has likely failed and must be replaced.

5. 5

   Recalibration

   After replacing the valve or controller, use a dealer-level diagnostic tool (such as the Case IH EST or Jaltest) to clear the fault codes, perform spool valve coding, and recalibrate the rear lift/hitch system.