Case IH 519008-07 - UCM – UCM: Front suspension rod pressure not changing

The system is commanding a change in the front suspension rod pressure (to adjust ride height, firmness, or damping), but the pressure transducer on the rod side of the suspension cylinder does not detect a change in pressure. This indicates a failure to raise or lower pressure, which is typically caused by a faulty pressure transducer, a stuck suspension lock valve, a damaged wiring harness, or a hydraulic supply issue to the front suspension manifold.

• MAGNUM AFS Connect
• Case IH Magnum 180 AFS Connect
• Case IH Magnum 200 AFS Connect
• Case IH Magnum 240 AFS Connect
• Case IH Magnum 280 AFS Connect
• Case IH Magnum 310 AFS Connect
• Case IH Magnum 340 AFS Connect
• Case IH Magnum 380 AFS Connect
• Case IH Magnum 400 AFS Connect

1. 1

   Harness & Routing Inspection: Check the wiring harness and plugs leading to the front suspension valve block. Note: A known issue on Magnum tractors is that the harness to the height potentiometer and lockout valve can get damaged/chafed near the bottom of the engine fan shroud due to poor routing.

2. 2

   Sensor Verification: Check the front suspension rod pressure transducer for proper voltage and range. Ensure it is not shorted to ground or open.

3. 3

   Solenoid Testing: Check the front suspension lock valve solenoid for an open circuit or short to ground.

4. 4

   Hydraulic Supply: Verify that adequate hydraulic pressure is reaching the front suspension manifold and that the system is not suffering from a low regulated supply pressure.

5. 5

   Calibration Check: Verify via the AFS Pro 1200 monitor if the front suspension is enabled and check if the suspension travel range has lost its calibration.

1. 1

   Secure the Machine

   Park the tractor on a level surface, engage the parking brake, and ensure the front suspension is fully lowered or mechanically supported before opening any hydraulic lines.

2. 2

   Repair Wiring

   If harness damage is found near the fan shroud or valve block, repair the broken wires and secure the harness with zip ties away from moving parts and vibration points.

3. 3

   Replace Faulty Sensors/Valves

   If the rod pressure transducer fails electrical testing, depressurize the system and replace the sensor on the right side of the suspension valve block. If the lockout solenoid is stuck or electrically failed, replace the solenoid cartridge or the entire directional control valve block.

4. 4

   Reassemble and Bleed

   Install new components, ensuring protective caps (like the valve cap plate cover) are securely fastened to protect the spool cartridges from environmental damage.

5. 5

   Recalibrate

   Use the tractor's AFS Pro 1200 display or a dealer diagnostic tool to clear the UCM fault codes and perform a front suspension travel range calibration.