Case IH 519076-05 - UCM – UCM: Rear hitch top link retract solenoid circuit

The controller is detecting a 'current below normal' or an open circuit condition in the Rear hitch top link retract solenoid circuit. This means the electrical current flowing to the top link retract solenoid is lower than the expected threshold, which is typically caused by a broken wire, a disconnected plug, or a burnt-out (open) solenoid coil.

• MAGNUM AFS Connect
• Puma 125
• Puma 165
• Puma 180
• Puma 195
• Puma 210
• Puma 225 CVX
• Maxxum Tier 3
• Maxxum MXM
• Farmall 95U
• Farmall 105U
• Farmall 115U Pro

1. 1

   Identify the circuit for the top link retract solenoid, designated as Wire Number 4056 (W - White).

2. 2

   Locate the UCM (often behind the operator's seat) and check Connector CN3-B, Pin 6 for the top link retract solenoid wire.

3. 3

   Inspect the wiring harness from the UCM to the rear hitch valve block for chafing, breaks, or pinch points.

4. 4

   Disconnect the plug at the retract solenoid on the hitch valve block and check for water ingress, corrosion, or pushed-out pins.

5. 5

   Measure the resistance across the solenoid coil pins. An infinite reading (OL) confirms the coil is internally open. If good, check for continuity on the white wire (4056) between the solenoid plug and Pin 6 on UCM Connector CN3-B.

1. 1

   Power Down

   Turn off the tractor. Always disconnect the two earth (ground) cable connections at the battery prior to performing major electrical repairs to prevent damage to the electronic and electrical systems.

2. 2

   Access the Valve Block

   Locate the rear hitch control valve assembly at the rear of the tractor.

3. 3

   Isolate the Fault

   Based on your diagnostic checks, determine if the fault is in the wiring harness (Wire 4056) or the solenoid itself.

4. 4

   Repair Wiring (If Applicable)

   If wire 4056 is broken between the UCM and the valve block, repair the wire using appropriate weather-sealed splice connectors.

5. 5

   Replace Solenoid (If Applicable)

   If the solenoid coil is open, remove the retaining nut holding the solenoid coil to the valve cartridge. Slide the old coil off and install the new replacement solenoid. Torque the retaining nut to OEM specifications.

6. 6

   Reassemble and Clear Codes

   Reconnect the battery ground cables. Turn the key on and use the tractor's Pro 1200 monitor (or equivalent AFS display) to navigate to the 'Faults and Warnings' menu to verify the code has moved from 'Active' to 'Inactive', then clear the inactive faults. Test the rear hitch top link retract function.