Case IH 13024 – Instrument Cluster (ADIC / ICU3) or Universal Control Module (UCM): Supply voltage 12VU2 - voltage too low

This fault code indicates that the voltage on the 12VU2 power supply rail has dropped below the acceptable operating threshold. The 12VU2 rail supplies voltage to critical subsystems, such as the Electronic Draft Control (EDC) Top/Side Link load compensation, the park brake solenoid, and other implement/chassis controls.

• MAXXUM T4E
• Puma 125
• Puma 140
• Puma 210
• Magnum 235-340 Series 4
• Steiger

1. 1

   Check the main fuse panel and UCM enclosure for blown fuses related to the 12VU2 circuit (often labeled as EDC or Park Brake supply).

2. 2

   Use the tractor's built-in H-Menu diagnostics (H9 - Voltmeter diagnostic) to monitor the live voltage reading for the 12VU2 channel (Channel 215 on connector X954 / CN3A). Watch for sudden voltage drops while wiggling the harness.

3. 3

   Inspect the wiring harness and connectors between the UCM/Cluster and the supplied components (EDC solenoids, park brake solenoid) for chafed wires or loose connections.

4. 4

   Test the power control relays in the UCM enclosure to ensure they are closing properly and allowing voltage to reach the 12VU2 rail.

1. 1

   Power Down

   Turn off the tractor, apply the parking brake, and disconnect the battery ground cable to ensure safety while working on the electrical system.

2. 2

   Replace Blown Fuses/Relays

   If a blown fuse or faulty relay was identified during diagnostics, replace it with a component of the exact same amperage/rating.

3. 3

   Repair Wiring

   If the harness is chafed and shorting to the chassis (causing the voltage drop/blown fuse), cut out the damaged section of wire, solder in a replacement segment, and seal it with heat-shrink tubing. Secure the harness away from pinch points.

4. 4

   Clear Fault Codes

   Reconnect the battery. Enter the instrument cluster's diagnostic menu (H8 menu) to clear the stored fault codes and reset the EEPROM values.

5. 5

   Verify Repair

   Start the tractor and operate the systems powered by the 12VU2 rail (e.g., engage/disengage the park brake, operate the rear hitch/EDC). Verify that code 13024 does not return.