Case IH 519163-02 - VCM – VCM / UCM: ISOBUS automation switch circuit fault

The control module has detected an electrical circuit error (such as an open circuit, short, or resistance issue) specifically on the circuit monitoring the ISOBUS quick-set/automation switch.

• MAGNUM AFS Connect
• Steiger AFS Connect series
• 250 Series Axial-Flow Combines

1. 1

   Inspect the ISOBUS automation switch (typically located on the armrest/multi-function handle) for physical damage or sticking.

2. 2

   Trace the wiring harness from the automation switch back to the VCM/UCM. Look for chafed wires, pinched harnesses, or exposed copper that could cause a short or open circuit.

3. 3

   Disconnect the switch and the VCM/UCM connectors. Check for bent, corroded, or pushed-out pins.

4. 4

   Using a multimeter, verify continuity across the switch when pressed. Check the circuit for proper reference voltage and ensure there is no short to ground.

1. 1

   Power Down

   Turn off the machine and disconnect the battery to prevent electrical spikes during repair.

2. 2

   Access the Switch

   Remove the necessary trim panels on the armrest console to access the underside of the ISOBUS automation switch.

3. 3

   Disconnect and Replace

   Unplug the electrical connector from the faulty switch. If the wiring harness tested good during diagnostics, remove the faulty switch from its mounting bezel and snap the new switch into place.

4. 4

   Reassemble

   Reconnect the wiring harness and reinstall the armrest trim panels.

5. 5

   Recalibrate/Test

   Reconnect the battery and power on the machine. Clear the inactive fault codes from the AFS Pro 1200 display.

6. 6

   Functional Test

   Engage the automation system (e.g., press the top of the Automation switch). Verify that the automation icon (such as the letter "A") displays on the monitor without triggering the 519163-02 code.