Disabling Theftlock(R)

The Theft Deterrent is disabled from the secure mode by the following sequence of operations.
1. Battery and ignition voltages applied and radio OFF
2. Depress buttons 1 (REV) and 4 (NR or RDM) for 5 seconds. The display will show SEC, indicating the unit is in the secure mode.
3. Using HR and MN buttons, enter the correct code number. The initial key press of either button will cause the display to indicate 000, the last three digits of the 3 1/2 digit user code. Subsequent key presses of the HR button will cause the left 3 1/2 digits to increment and depressing the MN button will cause the right two digits to increment. The digits will continuously increment at a rate of once every 1 second for the first two increments and then once every 250 milliseconds, as long as the button is depressed. The digits will also increment by one with every momentary depression.
4. Depress the AM/FM button. If the display shows--, the disabling sequence was successful (the numbers matched the user-selected code or the factory backup code) and the unit is in the unsecured state. If the display shows SEC, the numbers did not match either of the codes and the unit will remain in the secure state.
The display will revert to TOD after 15 seconds.

If the security 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.