Case IH 1487-04 - ICM – ICM: Display failure - TFT_LED (TFT backlight supply)

The "-04" Failure Mode Identifier (FMI) specifically indicates that the Vkey line has failed due to a short to ground ("curto com o terra") or a blown fuse ("fusível queimado"). This means the circuit supplying power to the display's TFT backlight is grounded out or has lost its fused power source.

• MAGNUM AFS Connect
• Magnum AFS Connect (250, 280, 310, 340, 380, 400)
• Steiger AFS Connect (420, 470, 500)

1. 1

   Inspect the 5A unswitched B+ fuse for the Instrument Cluster Module (e.g., fuse F-068) for a blown fuse on the Vkey line.

2. 2

   Check the wiring harness supplying the display and ICM for any chafing, bare wires, or pinching that would cause a short to ground.

3. 3

   Ensure the machine's batteries are fully charged and that the connections are secure.

1. 1

   Power down modules

   Turn the ignition key to the OFF position. Wait 2 to 5 minutes after turning the key off before disconnecting the batteries to allow the modules to power down correctly.

2. 2

   Disconnect batteries

   Disconnect the batteries.

3. 3

   Test and replace fuses

   Locate the cab fuse panel and test the fuses associated with the ICM (such as the 5A F-068 fuse). Replace any blown fuses.

4. 4

   Trace and repair wiring

   If the fuse blows again immediately upon restoring power, use a multimeter to trace the Vkey line/TFT backlight supply circuit between the ICM and the display to locate the short to ground. Repair the damaged wiring.

5. 5

   Replace display or ICM

   If the wiring and fuses are intact but the fault persists, the AFS Pro 1200 display or the ICM itself has an internal hardware short and must be replaced.

6. 6

   Connect diagnostic tool

   If the ICM is replaced, connect the Electronic Service Tool (EST) to the CAN1/ISOBUS diagnostic connector (Connector 1).

7. 7

   Configure new ICM

   Select the configuration item in the EST toolbar, go to general configuration, and configure the new ICM to match the tractor's specific parameters (e.g., engine type, transmission, etc.).