Case IH 522826-06 - PCM – PCM (Processing and Connectivity Module): WiFi/BT antenna short circuit to ground

The signal wire for the Wi-Fi/Bluetooth antenna has shorted to the chassis ground or the cable's own shielding, which disables the module's ability to transmit or receive local wireless data.

• MAGNUM AFS Connect
• Magnum 400
• Steiger AFS Connect
• Steiger 525 Quadtrac
• Optum
• Puma
• Axial-Flow 160
• Axial-Flow 260
• Axial-Flow 7260
• Axial-Flow 8250
• Axial-Flow 8260
• Patriot 50 Series

1. 1

   Locate the PCM (Processing and Connectivity Module) and identify the antenna ports located on the front of the unit.

2. 2

   Trace the Wi-Fi/BT antenna coaxial cable from the PCM to the antenna mounting location (usually the cab roof). Look for severe pinches, cuts, or areas where the cable may have chafed against the cab frame, causing the internal wire to touch the grounded chassis.

3. 3

   Disconnect the Wi-Fi/BT antenna cable from the PCM. Inspect the connector for bent pins, moisture intrusion, or internal corrosion that could bridge the signal pin to ground.

4. 4

   Using a digital multimeter, test for continuity between the center signal pin of the antenna cable and the outer ground shield. If there is continuity, the short is confirmed within the antenna or its cable harness.

1. 1

   Power down machine

   Power down the machine and turn off the main battery disconnect switch.

2. 2

   Disconnect faulty cable

   Disconnect the faulty Wi-Fi/BT antenna cable from the front port of the PCM.

3. 3

   Unroute damaged cable

   Carefully unroute the damaged antenna cable from the cab trim/headliner, noting the original routing path.

4. 4

   Remove old antenna

   Remove the old antenna assembly.

5. 5

   Mount new antenna

   Mount the new Wi-Fi/BT antenna. Ensure the antenna is mounted at least 20 cm (8 inches) away from the PCM itself and any other transmitting antennas (like AM/FM, CB, or Cellular/GNSS antennas) to avoid signal interference.

6. 6

   Route new cable

   Route the new coaxial cable back to the PCM. Secure it with zip ties, ensuring there are no sharp bends or pinch points that could cause a future short circuit. Note: The use of extension cables is not supported and will degrade performance.

7. 7

   Connect new cable

   Connect the new cable to the designated Wi-Fi/BT port on the front of the PCM.

8. 8

   Verify repair

   Restore power, turn on the machine, and verify via the AFS Pro display that fault code 522826-06 is now inactive. Test the Wi-Fi/Bluetooth connection to confirm the repair.