Case IH 519008-03 - UCM – UCM: Front suspension rod pressure sensor voltage high.

The control module is detecting a voltage signal from the front suspension's rod-side pressure sensor that exceeds the normal operating range (short to power or open circuit). This prevents the suspension system from accurately determining the hydraulic pressure on the rod side of the suspension cylinders, which can disable the active suspension damping and leveling functions.

• MAGNUM AFS Connect
• Magnum AFS Connect Series
• Puma Series
• Optum Series

1. 1

   Depressurize and Check Baseline: Using the Electronic Service Tool (EST) or the tractor's display (Trans FSUS view pressure page), monitor the rod and piston pressures. Manually depressurize the suspension system. With zero pressure, both sensors should read below 40 psi (approx. 275 kPa). If the rod sensor still reads high voltage/pressure, the sensor is likely faulty or there is a wiring issue.

2. 2

   Wiring & Connector Inspection: Inspect the 3-pin electrical connector at the rod pressure sensor. Look for corrosion, pushed pins, or a short-to-power in the wiring harness leading back to the UCM.

3. 3

   Sensor Swap Test: Swap the rod pressure sensor with the piston pressure sensor. If the fault code changes to the piston side (e.g., 519009-03), the sensor is internally shorted and must be replaced. If the fault remains on the rod side, the issue is in the wiring harness or the UCM.

4. 4

   Inspect Valve Orifices: Remove the hydraulic lines on the front side of the suspension valve block and check the internal brass orifices. Ensure they have not backed out, which can cause erratic pressure readings or calibration failures.

1. 1

   Depressurize the System

   Locate the level control block (typically located on the top of the rear axle housing or near the suspension accumulators). Locate the manual adjusting screws (thumb screws) on the solenoid valves. Screw in the screws for both the piston side and the rod side individually. This dumps the pressurized oil back into the tank.

2. 2

   Disconnect Power

   Turn off the tractor and disconnect the battery to prevent electrical shorts.

3. 3

   Remove the Sensor

   Locate the rod-side pressure sensor on the suspension control block. Disconnect the 3-pin electrical connector.

4. 4

   Replace the Sensor

   Unthread the faulty pressure sensor from the block. Install the new sensor and tighten it to the OEM torque specification.

5. 5

   Reconnect

   Plug the 3-pin electrical connector back into the new sensor.

6. 6

   Restore Pressure

   Back out the manual depressurization screws on the level control block to allow the system to build pressure again.

7. 7

   Calibrate

   Start the tractor and use the EST or the in-cab display to perform a Front Axle Suspension Calibration. This ensures the UCM learns the baseline voltage of the new sensor.