Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

The antenna signal circuit is a coaxial cable that carries the radio signal information received by the antenna. The antenna cable also provides a path for DC current for powering the antenna.

This test is run every 300 milliseconds.

The digital radio receiver (DRR) detects an antenna fault.

The radio displays "No XM Signal" or "Check Antenna"

Schematic Reference

Radio/Audio System Schematics

Connector End View Reference

Entertainment Connector End Views

Description and Operation

Radio/Audio System Description and Operation

Electrical Information Reference

Special Tools Required

EL-48028 Digital Radio Test Antenna

1. Ignition OFF, disconnect the antenna coax from the DRR. Connect the test antenna to the DRR.
2. Turn the ignition ON, radio ON tuned to XM. Verify that DTC B1259 is not current.

⇒	If the DTC B1259 is still current, replace the DRR.

3. Ignition is OFF. Disconnect the DRR antenna from the coaxial cable. Test the resistance of the antenna coaxial cable center conductor from end to end. Verify the resistance is less than 5 ohms.

⇒	If the resistance is greater than 5 ohms, replace the antenna coaxial cable.

4. Test the resistance of the antenna coaxial cable outer shield from end to end. Verify the resistance is less than 5 ohms.

⇒	If the resistance is greater than 5 ohms , replace the antenna coaxial cable.

5. Test the resistance of the antenna coaxial cable between the center conductor and the outer conductor. Verify there is infinite resistance between both conductors.

⇒	If there is less than infinite resistance between the inner conductor and the outer conductor of the coaxial cable, replace the antenna coaxial cable. If the coaxial cable tests normal, replace the digital radio antenna.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.