Case IH 1065 - UCM – UCM: EDC Hydraulic valve lower solenoid – short circuit

The Electronic Draft Control (EDC) system has detected a short circuit (either to ground or to a voltage source) in the electrical circuit that controls the lower proportional solenoid valve. This solenoid is responsible for shifting the valve spool to allow hydraulic fluid to return to the tank, which lowers the rear hitch. When this circuit shorts, the controller disables the circuit to prevent damage, resulting in the hitch being unable to lower properly or drifting.

• VESTRUM CVX
• Puma Series (140, 165, 180, 195, 210, 225 CVX)
• Maxxum Series (MXM 120, 130, 140, 155, 175, 190)
• Magnum Series (210, 215, 245, 275, 305, 7200 series)
• Steiger Series
• Farmall Series (models with CVT and cab)

1. 1

   Disconnect the tractor's battery for a short period to reset the electronic control systems and verify if the code is a transient error.

2. 2

   Locate the EDC hitch control valve block at the rear of the tractor. Inspect the wiring harness and the 2-pin connector at the lower solenoid for melted plastic, chafing, or water ingress that could cause a short circuit.

3. 3

   Unplug the connector from the lower solenoid. Using a multimeter, measure the resistance across the solenoid pins (Pin A to Pin C / Pin B to Pin C). It should be between 3.8 and 4.2 Ohms. A reading of 0 Ohms or significantly below spec indicates an internal short in the solenoid coil.

4. 4

   Check the tractor-side wiring harness for continuity to ground or an unwanted short to a 12V power source.

1. 1

   Preparation

   Lower the rear hitch completely to the ground to relieve trapped hydraulic pressure in the lift cylinders. Turn off the tractor and disconnect the battery.

2. 2

   Access the Valve

   Locate the EDC hydraulic valve block and identify the lower proportional solenoid.

3. 3

   Connector Replacement (If Applicable)

   If the diagnostic checks revealed a melted or shorted connector, cut the damaged connector off the harness and splice in a new 2-pin female pigtail connector.

4. 4

   Solenoid Replacement

   If the solenoid coil failed the resistance test, remove the retaining nut at the end of the solenoid stem and slide the faulty coil off the cartridge valve. (If the cartridge valve itself is physically stuck or damaged, unscrew the entire cartridge from the valve block, catching any residual oil).

5. 5

   Installation

   Slide the new solenoid coil onto the valve stem and secure it. Plug the 2-pin electrical connector back into the solenoid.

6. 6

   Clear Codes

   Reconnect the battery. Use the tractor's instrument cluster H-Menu to clear the codes. Access the 'HC' menu to erase all stored error codes without erasing the hitch calibration information. (Note: Do not use the 'H8' menu unless you intend to wipe all EEPROM calibration values back to factory defaults).

7. 7

   Testing

   Start the tractor and operate the EDC raise/lower switches to confirm the hitch moves smoothly and the 1065 code does not return.