2000 GMC Safari, lost power to the vehicle. The radio did disply 'loc' and now displays 'InOP'. Please Help

That is a security "feature" on GM radios to deter theft. The following instructions has had sucess with other GM vehicles. If not, only a dealer has the equipment to get past lock screen.

This works on vettes with theftlock. Try it on the tahoe and let us know....




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 on page 3-27 in your Y2K Owner's manual. Use the code from STEP 11 instead of your personal code. Note: This tip originated from LOTZAHP, Austin TX (credit must be given where credit is due). I verified it on an Y2K C5 with a locked radio - mine.
http://chevroletforum.com/forum/tahoe-suburban-25/help-radio-locked-8220/

Follow these steps to unlock your GM Delco Radio:
1. Turn the ignition ON (The Delco radio displays "LOC" or "INOP").

A. If your radio says "INOP" then you have entered too many wrong codes. You will need to run the vehicle for one hour or turn the key into the ON position for one hour before you can proceed to Step 2.

2. Looking at the face of your GM Delco radio, hold down the preset buttons 1&4 or 2&3 for approximately 10 seconds. The radio display changes from "LOC" to a three-digit number. Write this number down.

3. Press the AM/FM button. The radio display changes to another three-digit number. Write this number to the right of the first one.

4. You now have a six-digit number, the first three digits are from STEP 2 and the last three digits are from STEP 3, you will have a number like this (612-622).

A. NOTE: Saturn and GEO vehicles will only display a four-digit number. The fourth digit will be displayed half the size of the first three digits. Example: 2193.

Hope helps (remember rated and comment this).

How to Reset GM Theft lock Radio's
Article Disclaimer: This article is meant to be used by Delco Radio owners to reset there radios. In no way is it meant to be used for any unethical or unlawful ways.

Purpose
The following instructions will allow you to reset any GM (General Motors), Cadillac, Oldsmobile, Buick, Pontiac theft lock radio.

Requirements
The theft lock radio must be in "LOC" mode.

Procedure:
1. Turn the ignition ON (The radio should display "LOC")
2. Hold down the Radio Presets 2 and 3 buttons for six seconds
3. The radio display changes from LOC to a three-digit number. Write this number down. You now have fifteen seconds to complete the next step.
4. Press the AM/FM button
5. The radio display changes to another three-digit number. Write this number to the right of the first one
6. You now have a six-digit number, the first three digits are from STEP 03 and the last three digits are form STEP 05
7. Call 1-800-537-5140
8. Press 1 then # (pound). You'll hear "Invalid Code, try again"
9. Press 139010 or 106010 or 206010 or 202107 then # (pound). You will be asked to enter your four or six digit code followed by *
10. Enter the number from STEP 6 then *
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.

Dealership Codes
139010
106010
206010
202107

Troubleshooting
If you fail to enter the correct code eight times, the radio goes into INOP mode. You have to wait an hour with the ignition on before the radio returns to LOC mode.

To Read the original article or read similar articles please visit kingbain.com/how-to/unlock-gm-theftlock-radio-s

Good luck (remmeber comment and rated this).

Does your GM car or truck Radio display LOC and does not turn on? Chevrolet, Buick, Pontiac, GMC, Cadillac, Oldsmobile vehicles used a theft system to lock the radio when power is lost. This system was used from the ealy 1990's to the early 2000's.

Instructions:

1. If your radio displays the word LOC, you can retrieve a set of factory numbers in the radio that enable you to get a backup unlock code. If the radio says INOP, you will have to leave the key in the "ON" position, or let the car run for at least 1 hour before you attempt any unlock procedure. INOP means a secondary theft lock due to too many false attempts to unlock the radio.
2. Looking at the face of your GM Delco radio, hold down the preset buttons 1 & 4 OR 2 & 3 (Depending on year and model) for approximately 10 seconds or until a set of 2 or 3 numbers comes up on the display. Write the numbers down.
3. Next press the AM / FM button. A new set of 3 numbers will now show. Write these numbers down. You will then need to call a 1-800 phone number with these numbers to get the unlock code. There are many sites on the internet that can get it for you- for a small fee. Or, try calling your local GM Dealer and ask for them to do it. Many times they will do it for free. It only takes a minute.
4. Once you have the unlock code, enter it by pressing the MIN button until the display shows the last 2 digits of the unlock code, then press the HR button until the first 2 numbers or shown. Then press the AM / FM button to enter the code. The radio will now display SEC, and normal function is restored.

Also, its possible that you need RESET your GM Radio; this is the procedure: While performing maintenance on your car, you may disconnect the radio from the battery in your GM vehicle. GM cars contain Delco radios that are protected by Theftlock, which locks the radio after it has been disconnected from a power source. Iit can only be reset and unlocked with a car-specific security code. Identifying the security code for your GM vehicle is the only way to reset the car radio and disable the Theftlock protection device.

Instructions:

1. Turn on your car. Your Delco radio will show "LOC" in the LED display.
2. Press and hold down both the second and third preset buttons. Hold these buttons down for at least six seconds.
3. Write down the two- or three-digit code that appears in the LED display.
4. Press the AM/FM button on the radio.
5. Write down the next two- or three-digit code that appears in the LED display. You should be left with either a four- or six-digit number. Turn off your car.
6. Call the Delco radio automated customer support line at 1-800-537-5140.
7. Press "1" and then press the pound sign. The automated voice should respond "Invalid code, try again."
8. Enter the number 139010 into your phone and then press the "*" sign.
9. Enter the four- or six-digit number you wrote down from Steps 3 and 5, and then press the "*" button.
10. Write down the four-digit code given by the automated voice.
11. Turn on your car. Enter the Delco unlock code using the procedure outlined by your GM owner's manual. Normally, the unlock code is entered with the "HR" and "MN" buttons on your radio.
12. Press the AM/FM button. If you have entered the code correctly, your LED display will read "SEC" and the radio will be unlocked.
    

Also can check your Does your GM car or truck Radio display LOC and does not turn on? Chevrolet, Buick, Pontiac, GMC, Cadillac, Oldsmobile vehicles used a theft system to lock the radio when power is lost. This system was used from the ealy 1990's to the early 2000's.
jQuery('.intro .thumbnail').each(function(i,e){ jQuery(e).find('img').one('error',function(){ jQuery(e).remove(); }); });
Instructions:

1. If your radio displays the word LOC, you can retrieve a set of factory numbers in the radio that enable you to get a backup unlock code. If the radio says INOP, you will have to leave the key in the "ON" position, or let the car run for at least 1 hour before you attempt any unlock procedure. INOP means a secondary theft lock due to too many false attempts to unlock the radio.
2. Looking at the face of your GM Delco radio, hold down the preset buttons 1 & 4 OR 2 & 3 (Depending on year and model) for approximately 10 seconds or until a set of 2 or 3 numbers comes up on the display. Write the numbers down.
3. Next press the AM / FM button. A new set of 3 numbers will now show. Write these numbers down. You will then need to call a 1-800 phone number with these numbers to get the unlock code. There are many sites on the internet that can get it for you- for a small fee. Or, try calling your local GM Dealer and ask for them to do it. Many times they will do it for free. It only takes a minute.
4. Once you have the unlock code, enter it by pressing the MIN button until the display shows the last 2 digits of the unlock code, then press the HR button until the first 2 numbers or shown. Then press the AM / FM button to enter the code. The radio will now display SEC, and normal function is restored.

Also, its possible that you need RESET your GM Radio; this is the procedure: While performing maintenance on your car, you may disconnect the radio from the battery in your GM vehicle. GM cars contain Delco radios that are protected by Theftlock, which locks the radio after it has been disconnected from a power source. Iit can only be reset and unlocked with a car-specific security code. Identifying the security code for your GM vehicle is the only way to reset the car radio and disable the Theftlock protection device. jQuery('.intro .thumbnail').each(function(i,e){ jQuery(e).find('img').one('error',function(){ jQuery(e).remove(); }); });
Instructions:

1. Turn on your car. Your Delco radio will show "LOC" in the LED display.
2. Press and hold down both the second and third preset buttons. Hold these buttons down for at least six seconds.
3. Write down the two- or three-digit code that appears in the LED display.
4. Press the AM/FM button on the radio.
5. Write down the next two- or three-digit code that appears in the LED display. You should be left with either a four- or six-digit number. Turn off your car.
6. Call the Delco radio automated customer support line at 1-800-537-5140.
7. Press "1" and then press the pound sign. The automated voice should respond "Invalid code, try again."
8. Enter the number 139010 into your phone and then press the "*" sign.
9. Enter the four- or six-digit number you wrote down from Steps 3 and 5, and then press the "*" button.
10. Write down the four-digit code given by the automated voice.
11. Turn on your car. Enter the Delco unlock code using the procedure outlined by your GM owner's manual. Normally, the unlock code is entered with the "HR" and "MN" buttons on your radio.
12. Press the AM/FM button. If you have entered the code correctly, your LED display will read "SEC" and the radio will be unlocked.
    

Also can check 1999-Pontiac-Firebird-Owners-Manual (page 163), there are several information about to lock and unlock.


Hope this help (remember comment and rated this).

dealership......$25.00

How to Reset GM Theft lock Radio's

Article Disclaimer: This article is meant to be used by Delco Radio owners to reset there radios. In no way is it meant to be used for any unethical or unlawful ways.

Purpose

The following instructions will allow you to reset any GM (General Motors), Cadillac, Oldsmobile, Buick, Pontiac theft lock radio.

Requirements

The theft lock radio must be in "LOC" mode.

Procedure:

1. Turn the ignition ON (The radio should display "LOC")

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

3. The radio display changes from LOC to a three-digit number. Write this number down. You now have fifteen seconds to complete the next step.

4. Press the AM/FM button

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

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

7. Call 1-800-537-5140

8. Press 1 then # (pound). You'll hear "Invalid Code, try again"

9. Press 139010 or 106010 or 206010 or 202107 then # (pound). "it's really *<star>lol"
You will be asked to enter your four or six digit code followed by *

10. Enter the number from STEP 6 then *

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.

Dealership Codes

* 139010
* 106010
* 206010
* 202107

Troubleshooting

If you fail to enter the correct code eight times, the radio goes into INOP mode. You have to wait an hour with the ignition on before the radio returns to LOC mode.

this did not work it says code 139010 is invalid to I cant get past step 8 or 9 my number from step 3 is 702 and step 5 is 706 someone please help Im going crazy

Hello! You have done half of the work already! You can take the code, and the VIN to your vehicle; and call your local GM dealership. Tell them that you need the unlock code for the radio, and they will ask you for that information.

Also - there are 2 modes to the TheftLock - "LOC" or "SEC" and "INOP". Once the anti-theft is activated, the radio display will show "LOC" or "SEC" - you then have 8 attempts to enter your code. If after 8 attempts you don't enter the correct code, the display will change to "INOP". It is only at this time that you will need to wait one hour, with the ignition ON; before you can retry. After that - you will have only 3 attempts before the radio enters "INOP" mode again.

Hope this helps and good luck!

believe it or not you have to take it to the dealer to unlock it. Plus before you go there you have to leave the truck running for 30 minutes without touching the radio to get it out of inop mode. The radio got put in inop mode from loc mode by putting in the wrong code 3 times in a row. Once its out of inop you can take it to the dealer and they can call gm and get the unlock code for the radio (should cost 30-45 bucks at most dealers)

Good Day,

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 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 on page 3-27 in your Owner’s manual. Use the code from STEP 11 instead of your personal code.

I hope this helps

This came from:
http://answers.yahoo.com/question/index?qid=20070717061922AA7xMG3