Many GM Delphi radios incorporate theft lock technology. The purpose is to discourage theft, but it can also pose a problem to the vehicle owner in the event that the radio code is lost or forgotten. The radio will usually need to be reset if the battery has been disconnected. If you have purchased the vehicle and are unaware of the code required to reset the radio, look at the vehicle handbook which is usually in the glove box to see if the previous owner wrote down the radio code. If you don't have a code, you can still reset the radio.
Insert the key in the GM car's ignition and place the ignition in the ON position. The radio display should read "LOC."
Hold down both the Radio Preset "2" and "3" button for six seconds. The Delphi radio display will change from LOC to a three-digit code. Write down this code and quickly move to the next step.
Press the Delphi radio's "AM/FM" button. The Delphi radio will display another three-digit number. Write this second set of numbers down, the second set of numbers should follow the first set. Now you will have a six-digit number.
Call GM's automated customer service line at 1-800-537-5140.
Press the "1" key on your phone keypad, then "#". You will hear the automated voice say, "Invalid Code, try again."
Press either "139010," "106010," "202107" or "206010." Then hit "#."
Enter the six-digit code you wrote down from the radio display when prompted. Then hit the "*" key.
Write down the four-digit number that the automated service gives you.
Go back to your car and turn the ignition on. The radio should display "LOC" again.
Hit the "HR" button and use the numbered buttons or dials to display the first two digits of the four-digit code you received on the phone. Press the "MN" button and enter the last two digits of the four-digit number you received. The Delphi radio is now reset.
Insert the key in the GM car's ignition and place the ignition in the ON position. Turn the radio off.
Hold down the "MN" (minute) button on the Delphi radio panel until the LCD display reads "0000" Then release the button.
Press the "MN" button again until the last two digits on the Delphi display are identical to the last two digits of the radio security code.
Hold down the "HR" (hour) button on the Delphi radio until the first two digits on the LCD display match the first two digits of the radio's security code. Then release the button.
Hold the "AM/FM" button until the Delphi display reads "SEC." The radio is now reset.