1999 tahoe

I had my Tahoe disconnected from the battery for a few days while I was working on replacing the fuel pump.

Now, the on screen menu fromthe stereo reads, "L O C".

Does anyone know the procedure to unlock?

 

Hi

Below is the company procedure try this and let us know the result.


[hr]
[/align]
Radio Displays LOC, LOCKED, or CODE [/align]




Step

Action

Value(s)

Yes

No


1

[ol]Turn the ignition off.
Disconnect the negative battery cable for 1 minute.
Reconnect the battery cable.
Turn the ignition to run.
Turn the radio on. [/ol]
Does radio now operate?





Go to Step2


2

Important:It will say Theftlock® on the face of the radio.
Does the Radio have Theftlock?



Go to Step3




3

Is it possible to get the security code from the customer?



Go to Radio/Audio System Operation

Go to Step4


4

[ol]Turn the ignition on.
Turn the radio off.
Depress and hold Pre-set buttons 2 and 3.
Write down the first three digits that appear on the radio display.
Depress AM/FM, write down the second three digits that appear on the radio display. [/ol]
Did you receive the 6 digit Radio Display Code?



Go to Step5

Send Radio in for repair


5

Contact Delco Assistance to obtain a "Radio Back-up Code".



Go to Step6




6

[ol]Use the hours and minutes buttons on the radio and install the 4 digit "Radio Back-up Code".
Depress the AM/FM button.
"SEC" should display.[/ol]
Did the radio unlock?



Go to Step7

Repeat Step 6


7

Important:This will remove the original owner's code. The owner will then be able to reinstall their own personal security code.
Step 6 only unlocked the radio, if the original code is not known, repeat step 6.
Did the radio display?





Repeat Step 7[/align][/align]

 

Hey Jacky,

I ended up unlocking the stereo in my 1999Tahoe with this procedure that I borrowed.....it worked for mine, and I believe for any vehicles 2003 and later. Not sure about the newer vehicles.

The following procedure will give you a new code that you can use instead of your personal code. Using this new code, you can “unlock” your radio and then “re-lock” it with a new code if you wish. Prerequisites: The radio must be in LOC mode NOT in INOP mode. Let me explain. If you have activated the Theft-Deterrent feature of your radio and loose power, the radio goes into LOC (theftlock) mode. With the ignition on, you must use the MN and HR buttons to enter you personal code in order to unlock it (The instructions are on page 3-27 in your Y2K Owner’s manual). If you fail to enter the correct code eight (8) times, the radio goes into INOP mode. You have to wait an hour with the ignition on before the radio returns to LOC mode (go for a long drive somewhere).

Procedure:

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 in your Owner’s manual. Use the code from STEP 11 instead of your personal code.[/align]