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Antitheft and Alarm Systems: Testing and Inspection
UNLOCKING VEHICLE RADIO WITHOUT CUSTOMER UNLOCK CODEVEHICLES WITH THEFTLOCK OR DELCO-LOC RADIOS ONLY
If the security system is activated and the radio is disconnected from battery power, the radio will display "LOC". The radio will not turn on until the correct unlocking code is entered. If the customer code is lost or unavailable, contact your local GM dealership or an authorized Delco radio service center for additional assistance.