Case IH 2307-02 - UCM – UCM: UCM: Front pilot head #3 reporting loss of communication with vehicle controller

The CAN bus network has lost its signal to or from the #3 remote valve pilot head, which can fail internally and short out the CAN bus, killing communications and causing other valves or modules to drop offline.

• MAGNUM AFS Connect
• Magnum Series (210, 280)
• Puma Series (185, 200, 220, 240 CVT)
• Optum Series (270, 300)
• Steiger / Quadtrac Series (350, 370, 400, 420, 450, 470, 500, 580)

1. 1

   Isolate the faulty node by unplugging the electrical connector to the #3 front pilot head. If the rest of the system comes back online immediately, the #3 pilot head is internally faulty and shorting the CAN bus.

2. 2

   Inspect the wiring harness routing from the UCM to the remote valves. Look for water intrusion, dirt, or corroded pins at the UCM connectors (such as connector 92, which shares power/ground circuits).

3. 3

   Verify the UCM is receiving proper supply voltage, as communication faults are frequently triggered by supply voltage dropping below operational limits.

1. 1

   Turn off the tractor and relieve all hydraulic pressure from the remote valves.

2. 2

   Disconnect the wiring harness from the #3 pilot head valve assembly.

3. 3

   Unbolt and remove the faulty pilot head from the remote valve block.

4. 4

   Install the new pilot head valve assembly and torque to OEM specifications.

5. 5

   Reconnect the wiring harness.

6. 6

   Recalibrate the remote valves.

   Use the in-cab display or dealer diagnostic tool to recalibrate the remote valves so the UCM can learn the new actuator's sweep and limits.