Chevrolet 2003 Monte Carlo Owner's Manual page 175

Radio Display
Message
No Info
No Info
Not Found
XM Lock
Radio ID
Unknown
Check XM
XMTM Radio Messages
(cont'd)
in another vehicle. For security purposes, XM receivers
If you tune to channel 0, you will see this message
(channel 0) alternating with your XM Radio 8 digit radio ID label. This
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