Case IH 5313 – UCM (Universal Control Module): EHF Enable Switch STP

The control module is detecting an unexpected high voltage on the circuit for the switch that enables the Enhanced High-Flow (EHF) auxiliary hydraulics. A "Short to Power" (STP) means the signal wire is shorted to a 12V power source, either internally within the switch or somewhere in the wiring harness.

• skid steer
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)
• SV300
• SV340
• SR175
• SR250
• SR270
• TV380
• TV450B

1. 1

   Inspect the EHF Enable Switch (rocker switch or multi-function button) for physical damage or sticking.

2. 2

   Disconnect the switch and inspect the connector for moisture, corrosion, or bent pins bridging power and signal terminals.

3. 3

   Use a multimeter to test the switch for internal shorts.

4. 4

   With the switch disconnected, turn the key ON and probe the signal wire on the harness side. A 12V reading indicates the wiring harness is shorted to power.

5. 5

   Inspect the EHF Interlock Wire Harness and the main chassis harness for chafing, pinched wires, or melted insulation.

1. 1

   Turn off the machine, lower the boom to the ground, and disconnect the battery to prevent electrical damage.

2. 2

   Remove the trim panel or joystick housing to access the back of the EHF Enable Switch.

3. 3

   Disconnect the wiring harness from the switch.

4. 4

   If your multimeter testing confirmed the switch is internally shorted, remove the faulty switch from the panel/joystick and snap the new switch into place.

5. 5

   If the switch tested fine but the harness showed a short to power, trace the wiring harness back to the UCM.

   Locate the damaged section of the wire and repair it using heat-shrink butt connectors, or replace the affected harness section (such as the EHF Interlock Wire Harness).

6. 6

   Reconnect the switch and reassemble the console or joystick housing.

7. 7

   Reconnect the battery.

8. 8

   Turn the ignition ON, clear the fault codes from the UCM, and test the EHF auxiliary hydraulics to verify the repair.