1993 GMC Sonoma Owner's Manual - Page 153

4. Depress the BAND knob.Theradiowilldisplay 000. 5. Enter the second three digits of the code.The display will show the numbers as entered. 6. Depress the BAND knob.If the displayshows "- the disabling sequencewas successful. Thenumbersmatched the user-selected code or the factoryback-upcode and the unit is in the UNSECUREDmode. If the display shows SEC, the disabling sequencewas unsuccessful and the numbers did not matcheither of the codesand the unit will remain in the SECUREDmode. - "! Care of Your Compact Dlsc Handlediscscarefully. Store them in their original cases orother protective casesandaway from direct sunlight and dust. If the surface of a disc is soiled, dampena clean, soft cloth in a mild, neutral detergent solution and clean it, wiping from the center to the edge. Be sure never to touch the signal surface when handling discs.Pickup by grasping the outeredgesor the edge of the hole andtheouteredge. discs 3-25