Case IH 1931-07 - UCM – UCM: Aux Valve 2 Port Flow Command

Indicates a mechanical issue with the second rear auxiliary hydraulic valve. The rear pilot head #2 spool valve is physically stuck and not responding to the flow command.

• MAGNUM AFS Connect
• Magnum
• Puma
• Maxxum
• Optum
• Steiger

1. 1

   Visually and mechanically inspect the spool valve to see if it is physically protruding or stuck in the bore.

2. 2

   Verify the issue is not electrical by checking for short or open circuits in the wiring harnesses and connectors between the UCM and the auxiliary valve.

3. 3

   Verify that the hydraulic fluid is clean. Contaminated fluid or a clogged hydraulic filter (sometimes loaded with packing material or debris) can cause spool valves to stick or bind.

1. 1

   Relieve hydraulic pressure

   Relieve all hydraulic system pressure before servicing the valve block.

2. 2

   Disassemble valve

   Disassemble the rear pilot head #2 / auxiliary valve 2 for maintenance.

3. 3

   Inspect and polish spool valve

   Inspect the slide/spool valve. If the spool is rusted, roughened, or has minor burrs, it can sometimes be polished smooth with fine (metallographic) sandpaper.

4. 4

   Inspect pilot valve spring

   Inspect the pilot valve spring; if it is broken, it must be replaced.

5. 5

   Inspect pilot valve body

   Inspect the pilot valve body for internal scoring or damage. If the body is damaged, the entire pilot head/valve assembly must be replaced.

6. 6

   Reassemble and test

   Reassemble the valve, clear the inactive fault codes from the UCM using the monitor (e.g., Pro 1200) or a diagnostic tool, and test the hydraulic remote for proper operation.