Case IH 519082-06 - UCM – UCM: Rear hitch lower solenoid - overcurrent / short to ground

The controller has detected that the electrical circuit for the solenoid responsible for lowering the rear 3-point hitch is drawing too much current, typically due to a short circuit to ground or a failed solenoid coil.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect Series (Magnum 180, 200, 240, 250, 280, 310, 340, 380, 400)
• Case IH Steiger Series (Steiger 425 Rowtrac)

1. 1

   Disconnect the wiring harness from the UCM and test the resistance of the rear hitch lower solenoid circuit directly at the controller connector to check for a harness short.

2. 2

   Test the continuity from the UCM to the hitch lower solenoid and inspect the wiring harness for any areas where it may have rubbed through and shorted to the tractor chassis (ground).

3. 3

   Inspect the 2-pin electrical connector at the rear hitch lower solenoid for water ingress, corrosion, or melted pins, which can cause high current draw.

1. 1

   Disconnect power

   Turn off the tractor ignition and disconnect battery power.

2. 2

   Locate solenoid

   Locate the rear hitch lower solenoid valve on the rear hydraulic control valve block.

3. 3

   Disconnect connector

   Disconnect the 2-pin female electrical connector from the lower solenoid.

4. 4

   Test solenoid coil resistance

   Using a multimeter, measure the resistance across the pins of the solenoid coil itself. If the resistance is out of specification (shorted internally), the solenoid coil/valve must be replaced.

5. 5

   Inspect and repair wiring harness

   If the solenoid tests good, the fault lies in the wiring. Trace the harness back to the UCM, looking for pinched wires or damaged insulation. Repair the wiring harness as necessary.

6. 6

   Replace electrical connector

   If the connector housing is damaged or brittle, cut it back and splice in a replacement connector pigtail (see parts list below).

7. 7

   Reconnect and clear codes

   Reconnect the solenoid, restore battery power, and clear the fault codes.

8. 8

   Test and calibrate

   Run the tractor and test the rear hitch raise/lower functions. A hitch calibration may be required after hydraulic valve repairs.