I have the 4 digit code to unlock my 1997 Monte Carlo radio, however I don't remember the sequence to unlock it.

notify dealer with vin and proof of ownership for lock code

follow the circuit diagram

See my "Tips and Tricks" on how to unlock GM radios.

You should take it to the dealer and ask for the unlock code and the procedure for your radio for your year, make, and model car and radio combination.

You might be able to punch in the codes yourself, if they are kind enough to tell you how.

Good luck on this repair.

01. Turn the ignition ON (The radio displays LOC)

02. Hold down the Radio Presets 2 and 3 buttons for six seconds

03. The radio display changes from LOC to a three-digit number. Write this number down. Don’t take forever, fifteen seconds max before the next step.

04. Press the AM/FM button

05. The radio display changes to another three-digit number. Write this number to the right of the first one.

06. You now have a six-digit number, the first three digits are from STEP 03 and the last three digits are form STEP 05

07. Call 1 800 537 5140

08. Press 1 then # (pound). You’ll hear “Invalid Code, try again”

09. Press 139010 then # (pound). You will be asked to enter your four or six digit code followed by * (start)

10. Enter the number from STEP 6 then * (star)

11. Listen to the four-digit number and write it down. It will be repeated twice

12. Turn the ignition ON (The radio displays LOC)

13. Use the MN and HR buttons to enter the code from STEP 11

14. Press the AM/FM button. The radio display changes to SEC Your radio is now “un-locked” and usable. The Theft-Deterrent feature is STILL active! If you want to disable it, use the instruction on page 3-27 in your Y2K Owner’s manual. Use the code from STEP 11 instead of your personal code.

you need the unlock code from the manufacturer. I had a radio lock up but the company had me send it to them for them to unlock. i had to prove that i bought it and it was not stolen.

if the dealership cant unlock it then it be better off getting an aftermarket one

If the code is not at the back of your manual, try 0000 and if the radio locked it self from taking any more codes. Just disconnect the battery and that will reset the radio so you can re-enter the code. If 0000 did not work then log on to Radio-code.com, you can get your cod there for like $12.00 which is cheaper then the dealer and you get to know the codes as most dealer will just unlock the radio. Good luck and hope this helps, keep me posted if you have any more question.

Sorry to say this but you will need to go to your local gm dealer if this is a theftlock system. You wil need the serial number and proof of ownership for them to give you the unlock code.

if you have the log books check there first. if not u need to get the unlock code from the manufacturer dealership.