Radio & Codes
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
Do you have an owners manual? This is copied directly from page 3-27 of a 1999 owners manual.
Go to page 191
https://www.mygmlink.com/pdf/go2cont...99corvette.pdf
Theft-Deterrent Feature
THEFTLOCK is designed to discourage theft of your
radio. It works by using a secret code to disable all radio
functions whenever battery power is removed.
The THEFTLOCK feature for the radio may be used or
ignored. If ignored, the system plays normally and the
radio is not protected by the feature. If THEFTLOCK is
activated, your radio will not operate if stolen.
When THEFTLOCK is activated, the radio will display
LOC to indicate a locked condition anytime battery
power has been interrupted. If your battery loses power
for any reason, you must unlock the radio with the secret
code before it will operate.
Activating the Theft-Deterrent Feature
The instructions which follow explain how to enter your
secret code to activate the THEFTLOCK system. It is
recommended that you read through all nine steps
before starting the procedure.
NOTE: If you allow more than 15 seconds to elapse
between any steps, the radio automatically reverts to
time and you must start the procedure over at Step 4.
1. Write down any three or four-digit number from
000 to 1999 and keep it in a safe place separate from
the vehicle.
2. Turn the ignition to ACC or ON.
3. Turn the radio off.
4. Press the 1 and 4 buttons together. Hold them down
until --- shows on the display. Next you will use the
secret code number which you have written down.
5. Press MN and 000 will appear on the display.
6. Press MN again to make the last two digits agree
with your code.
7. Press HR to make the first one or two digits agree
with your code.
8. Press AM-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show REP to let you know that you
need to repeat Steps 5 through 7 to confirm your
secret code.
9. Press AM-FM and this time the display will show
SEC to let you know that your radio is secure. The
LED indicator by the volume control will begin
flashing when the ignition is turned off.
Go to page 191
https://www.mygmlink.com/pdf/go2cont...99corvette.pdf
Theft-Deterrent Feature
THEFTLOCK is designed to discourage theft of your
radio. It works by using a secret code to disable all radio
functions whenever battery power is removed.
The THEFTLOCK feature for the radio may be used or
ignored. If ignored, the system plays normally and the
radio is not protected by the feature. If THEFTLOCK is
activated, your radio will not operate if stolen.
When THEFTLOCK is activated, the radio will display
LOC to indicate a locked condition anytime battery
power has been interrupted. If your battery loses power
for any reason, you must unlock the radio with the secret
code before it will operate.
Activating the Theft-Deterrent Feature
The instructions which follow explain how to enter your
secret code to activate the THEFTLOCK system. It is
recommended that you read through all nine steps
before starting the procedure.
NOTE: If you allow more than 15 seconds to elapse
between any steps, the radio automatically reverts to
time and you must start the procedure over at Step 4.
1. Write down any three or four-digit number from
000 to 1999 and keep it in a safe place separate from
the vehicle.
2. Turn the ignition to ACC or ON.
3. Turn the radio off.
4. Press the 1 and 4 buttons together. Hold them down
until --- shows on the display. Next you will use the
secret code number which you have written down.
5. Press MN and 000 will appear on the display.
6. Press MN again to make the last two digits agree
with your code.
7. Press HR to make the first one or two digits agree
with your code.
8. Press AM-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show REP to let you know that you
need to repeat Steps 5 through 7 to confirm your
secret code.
9. Press AM-FM and this time the display will show
SEC to let you know that your radio is secure. The
LED indicator by the volume control will begin
flashing when the ignition is turned off.
Thread Starter
Melting Slicks
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Here is more information. I have one with a code that is already set. It is in the car and functioning ok. It was set when I bought the car but I do not know what the code is. How do I access it to find out what the code is? Or can I just go in and change it using the method in the manual. I ask the questions as I don't want to start fooling with it and find out that because it has a code already set that it will lockup and then not be usable until it is unlocked by a dealer.
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
I posted that excerpt from the owners manual thinking that you can just start the programming process and it will over-write the previous stored code, I didn't realize that you don't know the current code. I still think the over-write will work, but just in case here is the procedure to unlock a radio:
https://www.corvetteforum.com/techti...=164&TopicID=1
https://www.corvetteforum.com/techti...=164&TopicID=1
