Case IH 3598-05 - BCM – BCM: Radio switched power - open circuit

The control module has detected a break in the electrical circuit (an open circuit or infinite resistance) on the switched power supply line that provides ignition-switched 12V power to the cab's radio unit.

• MAGNUM AFS Connect
• Steiger AFS Connect

1. 1

   Check the cab fuse panel for a blown or poorly seated radio switched power fuse (often a 10A or 15A fuse).

2. 2

   Turn the ignition key to the ON position and verify if the radio powers up to confirm if switched power is genuinely missing.

3. 3

   Access the rear of the radio unit and inspect the main harness connector for backed-out pins, corrosion, or a disconnected plug.

4. 4

   Disconnect the radio harness and measure the voltage at the switched power pin on the harness side with the key in the ON position (should read ~12V).

5. 5

   Perform a continuity test on the switched power wire from the BCM output pin to the radio connector to isolate the break in the harness.

1. 1

   Disconnect Power

   Turn off the ignition and disconnect the negative battery cable to prevent accidental short circuits while working on the BCM and cab wiring.

2. 2

   Access the Harness

   Remove the necessary cab trim panels to access the rear of the radio and the routing path to the Body Control Module (BCM).

3. 3

   Repair the Wiring

   If the continuity test revealed a broken wire, locate the pinch point or break (commonly found where harnesses route behind tight dash panels or near the A-pillar). Splice and repair the wire using OEM-approved heat-shrink connectors.

4. 4

   Reseat Connectors

   If the wiring is intact, thoroughly clean the radio and BCM connectors with electrical contact cleaner. Reseat the connectors, ensuring the locking tabs click into place and no pins are pushed out the back of the connector housing.

5. 5

   BCM Software/Hardware Check

   If the wiring is perfectly intact but the BCM is failing to output voltage on that circuit, the BCM may require a software re-flash or replacement.

6. 6

   Reassembly and Clearing Codes

   Reconnect the battery. Turn the key to the ON position. Use the AFS Pro display or a DPA5 diagnostic tool to clear the inactive 3598-05 fault code. Verify that the radio turns on and the code does not return.