Case IH 1911 – VCM / UCM: VCM - Rail 12VH1 - Left And Right Pump Reverse Input Power Off.

The power supply (Rail 12VH1) to the left and right pump reverse input is disconnected, off, or experiencing a loss of voltage. This prevents the controller from properly commanding or monitoring the reverse function of the hydraulic drive pumps.

• skid steer
• SR130
• SR160
• SR175
• SR200
• SR210
• SR220
• SR250
• SV185
• SV250
• SV300
• TR270
• TR320
• TV380
• C227
• C232
• C238
• L213
• L216
• L218
• L220
• L221
• L223
• L225
• L230
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)

1. 1

   Check the main fuse box for blown fuses or faulty relays related to the UCM/VCM power supply, specifically the 'Micro UCM Power' relay (Position A7, A9)

2. 2

   Inspect the wiring harness connecting the VCM/UCM to the left and right pump reverse solenoids for chafed wires, disconnected pins, or corrosion

3. 3

   Verify that the unswitched 12-volt supply voltage is reaching the VCM/UCM and that the module is properly grounded

4. 4

   Test the left and right pump reverse input solenoids for internal shorts that may be pulling the voltage down and causing the module to cut power

1. 1

   Disconnect Power

   Turn off the machine and disconnect the negative battery cable before servicing electrical components.

2. 2

   Replace Faulty Relays/Fuses

   If the UCM power relay or associated fuses are blown, replace them with OEM equivalents.

3. 3

   Repair Wiring

   If the harness is damaged, repair the broken wires or replace the affected harness section (e.g., WIC Chassis Electro-Hydraulic Module harness).

4. 4

   Replace the VCM/UCM

   If power is reaching the module but Rail 12VH1 remains dead, the internal power supply of the UCM/VCM has failed. Unbolt the module bracket and disconnect the multi-pin connectors. Install the new UCM/VCM. Important Note: A new or remanufactured UCM/VCM is not plug-and-play. It must be flashed/programmed with the correct machine software using the Case IH Electronic Service Tool (EST) before use.

5. 5

   Clear Codes

   Reconnect the battery, turn the key on, and use the diagnostic tool to clear the DTCs. Test the machine's drive system in reverse to ensure the fault does not return.