Case IH 5393 – UCM (Universal Control Module): EHF Pump Solenoid(s) STP

This code indicates a Short to Power (STP) in the Enhanced High-Flow (EHF) pump solenoid circuit. The system has detected that the voltage on the EHF directional pump control circuit is higher than expected. This typically happens when the control wire is chafed and touching a 12V power source, or if the solenoid coil itself has suffered an internal short circuit.

• skid steer
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)
• SR175
• SR250
• SR270
• SV300
• SV340B
• TV380

1. 1

   Visually inspect the wiring harness from the UCM to the EHF hydrostatic pump assembly for pinched wires, melted insulation, or chafing where the harness routes along the frame or near moving loader arms.

2. 2

   Perform a voltage check by disconnecting the electrical connector at the EHF pump solenoid. With the key ON (engine off), probe the signal wire on the harness side. If it shows full battery voltage (12V) when the EHF auxiliary is not being commanded, the wiring harness is shorted to power.

3. 3

   Perform a solenoid coil resistance test. If the harness tests fine, use a multimeter to measure the resistance (Ohms) across the pins of the EHF pump solenoid itself. A reading of zero or near-zero indicates the solenoid coil is internally shorted.

1. 1

   Safety First

   Lower the loader arms completely (or engage the mechanical lock if they must be raised), turn off the machine, and disconnect the negative battery cable.

2. 2

   Locate the Solenoid

   Access the hydrostatic/hydraulic pump assembly (usually located under the cab, which may need to be tilted forward). Locate the EHF pump control PRV (Proportional Relief Valve) directional solenoids.

3. 3

   Disconnect

   Unplug the wiring harness connector from the faulty EHF pump solenoid.

4. 4

   Harness Repair (If Applicable)

   If your diagnostic checks revealed a short in the wiring, splice and repair the damaged section of the harness using weather-sealed heat-shrink connectors.

5. 5

   Solenoid Replacement (If Applicable)

   Remove the retaining nut or bolt at the end of the solenoid valve stem. Slide the faulty EHF solenoid coil off the valve cartridge. Slide the new solenoid coil onto the stem and secure it with the retaining nut.

6. 6

   Reassembly

   Plug the wiring harness back into the new solenoid. Ensure the connector clicks into place and is free of dirt/moisture.

7. 7

   Test

   Reconnect the battery, lower the cab, start the machine, and engage the EHF auxiliary hydraulics to verify proper operation and ensure the 5393 code has cleared.