Navigation cannot control XM radio

Review the audio system diagnostic section.
If you can only tune channel 000, 001, 174 or 247, make sure the audio unit is set to the channel mode (owner's manual), if it is set to channel mode, call XM satellite radio customer support and check the account activation status.

Go into the Diagnostic Menu and use the NAVI SYSTEM LINK test .
Is only the XM icon red?

YES - Check the connector at the XM receiver and navigation unit connector. If the connection is OK, substitute a known-good XM receiver, and recheck. If the symptom goes away, replace the original XM receiver.

NO - Go to step 2.
Substitute a known-good navigation unit NAVIGATION UNIT REMOVAL/INSTALLATION ), and recheck.
Can the navigation control the XM radio?

YES - Replace the navigation unit NAVIGATION UNIT REMOVAL/INSTALLATION ).

NO - Do the audio system troubleshooting.