Case IH 2914 – Transmission (Trans), Front Suspension, UCM, or ICU: 12VF3 voltage supply is low. (possible blown fuse*)

The control module has detected that the voltage on the 12VF3 power supply circuit has dropped below the normal operating threshold. The most common culprit is a blown fuse on that specific circuit.

• Magnum
• Magnum Tractors 235 - 340 (Series 4)
• Steiger Tractors STX 350 - 600
• Puma Tractors
• Combines 7140
• Combines 8240
• Combines 240 Series

1. 1

   Clear the error code and retest, as this code can sometimes be induced during cold starting.

2. 2

   Verify that the battery is fully charged and the alternator/charging system is operating at the correct voltage.

3. 3

   Inspect the main fuse box for a blown fuse on the 12VF3 circuit (often fuse F-022).

4. 4

   Inspect the wiring harness and connectors associated with the 12VF3 circuit for damage, loose connections, or bent pins.

5. 5

   If battery, fuse, and wiring are good, check the controller/ECU for internal faults.

1. 1

   Turn off the machine and remove the key from the ignition.

   Ensure the machine is completely powered down before accessing electrical components.

2. 2

   Access the main electrical fuse panel.

   Refer to your specific model's operator manual for the exact location, usually in the cab console or under the hood.

3. 3

   Locate the fuse for the 12VF3 circuit.

   In most Case IH schematics, this is designated as F-022 (a 15-Amp Mini fuse).

4. 4

   Pull the fuse and inspect it.

   If the internal filament is broken or scorched, the fuse is blown.

5. 5

   Replace the blown fuse with a new OEM 15A Mini Blue fuse.

   Do not use a fuse with a higher amperage rating.

6. 6

   Turn the key on and clear the fault code.

   Use your electronic service tool or the in-cab display to clear the fault code.

7. 7

   Start the machine and operate it to verify the code does not return.

   Ensure normal operation without the fault code reappearing.

8. 8

   Trace and repair dead short to ground if the new fuse blows immediately.

   If the new fuse blows immediately upon startup, you have a dead short to ground in the 12VF3 wiring harness that must be traced and repaired before replacing the fuse again.