Case IH 10028 – CCM: Suspension will not lower fault

The front axle suspension system is failing to depressurize or lower when commanded.

• VESTRUM CVX
• Magnum Series (235-340 Series 4, 275, 305)
• Puma Series (170-260 CVX and PowerDrive)
• Optum Series

1. 1

   Check system pressure sensors (rod and piston) using the Case IH Electronic Service Tool (EST) or A-post display. Both should read below 40 psi (302 kPa) when completely depressurized.

2. 2

   Inspect the internal brass orifices in the suspension valves by removing the hydraulic lines from the front side of the valve block to ensure they haven't backed out or been destroyed.

3. 3

   Check the front axle position sensor (potentiometer) voltage to ensure it reads within expected absolute limits and is free from physical damage or debris.

1. 1

   Depressurize the System

   Screw in the manual depressurization thumb screws on the suspension solenoid valve block to allow trapped oil to return to the tank.

2. 2

   Isolate Both Sides

   Depressurize the piston side and the rod side individually using their respective screws (1 = Piston side, 2 = Rod side).

3. 3

   Inspect/Replace Components

   Replace the faulty piston-side or rod-side pressure transducer if readings are incorrect. Replace the orifices or the affected cartridge valve if the brass orifices inside the valve block are damaged or missing.

4. 4

   Reassemble and Restore Pressure

   Reconnect any removed hydraulic lines and back out the manual depressurization thumb screws on the valve block to restore normal hydraulic function.

5. 5

   Calibrate the Suspension

   Use the Case IH EST to clear the 10028 fault code and run the front suspension calibration procedure so the CCM can relearn the absolute limits of the position sensor.