What is the procedure to changing an keyed ignition lock?

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Ignition what ? Switch ,Ignition lock cylinder ? New keys ? do they have the transponder pellet in the head. Do you have a security lit flashing when trying to start the vehicle ?
SECTION 419-01: Anti-Theft - PATS 1999 Mustang Workshop Manual GENERAL PROCEDURES Procedure revision date: 11/06/1998 Key Programming -Erase All Key Codes and Program Two Keys
Special Tool(s) > New Generation STAR (NGS) Tester or equivalent
418-F048 (007-00500) NOTE: This procedure is used when a customer needs keys programmed into the system and does not have two programmed ignition keys available. This procedure is also useful when programmed ignition key(s) have been lost or the ignition switch assembly has been replaced, and it is desired to erase key(s) from the passive anti-theft system (PATS) memory.
NOTE: This procedure will erase all programmed ignition keys from the vehicle memory and the vehicle will not start until two keys have been reprogrammed to the vehicle.
NOTE: Two PATS encoded keys with the correct mechanical cut must be available to perform this procedure. One or both of them may be the customer's original keys.
NOTE: If additional keys are to be programmed, refer to Key Programming - Program a Key Using Two Programmed Keys. If the remaining keys are with the customer and are not available with the vehicle, then instruct the customer to refer to the Owners Guide under the "Programming Spare [SecuriLock ® (North America), Safeguard ® (U.K.) or PATS for all other markets] Keys Procedure" for instructions on programming the remaining keys.

1. Turn the ignition switch from OFF to RUN.

1. Enter New Generation STAR/Service Bay Diagnostic System (NGS/SBDS). Follow the SECURITY ACCESS PROCEDURE to obtain security access.

1. From NGS/SBDS menu, select IGNITION KEY CODE ERASE.

1. NOTE: Do NOT select any additional commands from this menu.
   Turn the ignition switch to OFF and disconnect NGS.

1. Insert the first encoded key into the ignition lock cylinder and turn the switch to RUN for three seconds.

1. Insert the second encoded key into the ignition lock cylinder and turn the switch to RUN for three seconds.

1. The vehicle should now start with both ignition keys.

You'll need to take to the dealer

There is a special procedure involved in keying your fob to your car once the battery has been changed. You must lock and open the door with your key. Turn the ignition to "on"(not start) then push the fob's open and close button, then shut off ignition. This procedure is done everything the key battery is changed. Hope this can help you!
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Motorcycle Diagnostic Scanner

Programming
When
Key added or replaced. System malfunction.
How
Driver's door open and key removed from ignition switch. Insert key into ignition switch, then remove it. Within 5 seconds: Insert key into ignition switch, then remove it. Within 40 seconds: Close and open driver's door twice. Insert key into ignition switch, then remove it. Within 40 seconds: Close and open driver's door twice. Insert key into ignition switch. Close driver's door. Switch ignition ON and OFF once to program a new key code whilst retaining the original codes or twice to program a new key code whilst erasing the original codes. Remove key. System should now lock and unlock vehicle, once or twice depending which mode has been selected. Carry out the following button procedure within 40 seconds: Press key lock or unlock button once. Within 3 seconds: Press same key lock or unlock button once. System should now lock and unlock vehicle.
NOTE: If system locks and unlocks vehicle twice, programming procedure has not been completed. Repeat button procedure.
If required repeat button procedure to program remaining keys.
NOTE: To exit programming mode: Open driver's door. NOTE: A maximum of 4 keys can be programmed

This will work providing printed circuit is not damaged in remote

Here's a copy of a service bulletin on your problem.

I'll bet the dealer says $300 for parts and 2 hrs labor.:screwy:

Ignition Key - Will Not Turn And/Or Cannot Be Removed
NUMBER: 23-23-00
GROUP: Body
DATE: JUNE 30, 2000
SUBJECT:
Ignition Key Will Not Turn And/Or Cannot Be Removed
MODELS:
1997 - 2000 (NS) Town & Country/Caravan/Voyager
OVERVIEW:
This bulletin involves performing one or any combination of the following procedures; cutting a new ignition key, and/or adjusting transmission shifter cable, and/or replacing the ignition lock cylinder and/or replacing the ignition lock housing and switch assembly.
SYMPTOM/CONDITION:
1. Cannot turn the ignition key when attempting to start vehicle, this condition may be intermittent.
2. Unable to remove the ignition key from the lock cylinder.
PARTS REQUIRED:
AR(1)04778115 Key
AR(1)05003843AB Cylinder, Ignition Lock
AR(1)04690523 Assembly, Ignition Switch and Lock Housing
EQUIPMENT POSSIBLY REQUIRED:
Key Cutter such as Pentastar Service Equipment (PSE) IL-MK1-P2627 or
IL-ECM-100
T-27 Torx Bit
T-25 Torx Bit
T-10 Tamper Resistant Torx Bit
SR-706059 Lock Cylinder Build Kit, Pentastar Service Equipment (PSE)
DIAGNOSIS/REPAIR PROCEDURE:
DOES NOT REQUIRE HOISTS OR OTHER FULL SERVICE FACILITY SPECIAL EQUIPMENT. THIS REPAIR IS COMPATIBLE WITH DAIMLERCHRYSLERS MOBILE SERVICE PROGRAM.
SYMPTOM/CONDITION ONE
1. Ensure the steering wheel is centered and the vehicle is positioned on a level surface.
2. Disconnect the negative battery cable.
3. Insert ignition key into the ignition lock cylinder and attempt to rotate the key to the start position and then the accessory position.
4. If the key does not turn, remove the key from the lock cylinder and rotate it 180°. Reinsert the key into the lock cylinder and attempt to rotate the key. If the key does not turn skip to step 14. If the key does turn make a new key.
NOTE: USE THE KEY CODE ON THE VEHICLE INVOICE TO CORRECTLY CUT THE NEW KEY. KEY CODES ARE ALSO AVAILABLE USING THE D.I.A.L. SYSTEM, MAIN MENU OPTION 13. DO NOT USE A KEY DUPLICATOR TO MAKE THE NEW KEY.
5. Insert the new ignition key into the ignition lock cylinder and attempt to rotate the key to the start position and then the accessory position.
6. If the key turns, remove the key from the lock cylinder and turn it over 180°and reinsert the key into the lock cylinder. Attempt to rotate the key.
7. If the key turns, repeat steps 5 and 6 ten times. If the key continues to rotate smoothly the repair is complete. If the key fails to turn smoothly at each rotation attempt, continue to step 8.
8. Remove the ignition lock cylinder using the procedure outlined on page 8D-29 of the 2000 Town & Country, Caravan and Voyager Service Manual (Publication No. 81-370-0005). DO NOT ATTEMPT TO DISASSEMBLE THE Lock CYLINDER.
9. Build a new lock cylinder to the key code on the vehicle invoice, using the instructions in the Pentastar Service Equipment SR-706059 Lock Cylinder Build Kit.
10. Install the new ignition lock cylinder using the procedure outlined on page 8D-29 of the 2000 Town & Country, Caravan and Voyager Service Manual (Publication No. 81-370-0005).
11. Insert the new ignition key into the new ignition lock cylinder and attempt to rotate the key to the start position and then the accessory position.
12. If the key turns, remove the key from the lock cylinder and turn it over 180°and reinsert the key into the lock cylinder. Attempt to rotate the key.
13. If the key turns, repeat steps 11 and 12 ten times. If the key continues to rotate smoothly the repair is complete. If the key fails to turn smoothly at each rotation attempt, continue to step 14.
14. Remove the ignition lock housing and ignition switch as an assembly using the procedure outlined beginning on page 19-47 of the 2000 Town & Country, Caravan and Voyager Service Manual (Publication No. 81-370-0005).
NOTE: SKIP STEPS 13 AND 14 OF THE SERVICE MANUAL REMOVAL PROCEDURE SO THE IGNITION LOCK HOUSING AND IGNITION SWITCH ARE REMOVED AS AN ASSEMBLY.
15. Install a new ignition lock housing and ignition switch assembly, p/n 04690523, using the procedure outlined beginning on page 19-49 of the 2000 Town & Country, Caravan and Voyager Service Manual (Publication No. 81-370-0005).
NOTE: PRIOR TO PERFORMING STEP 2 OF THE SERVICE MANUAL LOCK HOUSING INSTALLATION PROCEDURE, INSTALL THEN REMOVE THE TWO LOCK CYLINDER HOUSING MOUNTING SCREWS INTO THE LOCK HOUSING MOUNTING HOLES TO CREATE THE THREADS IN THE HOLES.FAILURE TO CREATE THE MOUNTING HOLE THREADS PRIOR TO INSTALLATION TO THE STEERING COLUMN MAY CAUSE MISALIGNMENT OF THE LOCK HOUSING TO STEERING COLUMN AND DAMAGE BINDING OF STEERING COLUMN MAY RESULT.
STEPS 5 AND 6 OF THE SERVICE MANUAL INSTALLATION PROCEDURE FOR THE LOCK HOUSING ARE NOT NECESSARY FOR THIS TSB PROCEDURE.
WHEN PERFORMING STEP 9 OF THE SERVICE MANUAL PROCEDURE USE THE NEW LOCK CYLINDER THAT WAS BUILT IN STEP 9 OF THE SYMPTOM/CONDITION ONE DIAGNOSIS / REPAIR PROCEDURE OF THIS BULLETIN.
16. Insert the new ignition key into the new ignition lock cylinder and attempt to rotate the key to the start position and then the accessory position.
17. If the key turns, remove the key from the lock cylinder and turn it over 180°and reinsert the key into the lock cylinder. Attempt to rotate the key.
18. If the key turns, repeat steps 16 and 17 ten times. If the key continues to rotate smoothly the repair is complete.
SYMPTOM/CONDITION TWO
1. Check the operation of the shift lever. The shift lever should fall freely away from the driver when it is brought up into the Park position.
2. If the shift lever does not seat fully up and away from the driver the column will not allow the key to be removed.
3. If binding of the shift lever is discovered, adjust the transmission shift cable using the procedure outlined on page 21-114 of the 2000 Town & Country, Caravan and Voyager Service Manual (Publication No. 81-370-0005).

Retrain the fobs following the procedure in your owner's manual:


Once entering this procedure, programming the first transmitter erases all previous transmitters. You must program all transmitters.

Program one vehicle at a time. One transmitter could be programmed into other vehicles that are also on
program mode in close proximity.
1. Sit in the driver's seat.
2. Remove the ignition key from the ignition lock cylinder.
3. Close all vehicle doors.
4. Press and hold unlock on the door lock switch.
5. While holding the door lock switch in the unlock position, insert and remove the ignition key twice. Do
not rotate the ignition lock cylinder.
6. Insert the ignition key a third time leaving the key in the ignition lock cylinder. The ignition must remain
in the LOCK position for the rest of the procedure.
7. Release the door lock switch. You will hear three chimes. This chime feedback indicates that transmitter
programming is active.
8. Press and hold the lock and unlock buttons at the same time on the keyless entry transmitter for 12
seconds. You will hear two chimes. This chime feedback indicates that the transmitter has been
programmed successfully.
9. Repeat step 8 for the rest of the transmitters (for a total of 4 transmitters).
10. Exit this procedure by removing the ignition key from the ignition lock cylinder.

u must put a key to ignition and open a drive door 3 times and press and hold lock button

Ignition Lock Cylinder
Ford Taurus/Sable 1986-1995 Repair Information





REMOVAL & INSTALLATION

Functional Lock


The following procedure applies to vehicles that have functional lock cylinders. Such cylinders either have a key available or known key numbers from which a key can be made.

1. Disconnect the negative battery cable.
   
2. Turn the lock cylinder key to the RUN position.
   
3. Using a 1/8 in. (3mm) diameter wire pin or a small drift, depress the lock cylinder retaining pin through the access hole in the upper steering column shroud (under the ignition lock cylinder) while pulling out on the lock cylinder. Remove the lock cylinder from the column.
   

Using the key, turn the ignition lock cylinder to the RUN position, then depress the retaining pin using a wire pin or small drift

To install:

1. Install the lock cylinder by turning it to the RUN position and depressing the retaining pin. Insert the lock cylinder into its housing. Make sure the cylinder is fully seated and aligned in the interlocking washer before turning the key to the OFF position. This will permit the cylinder retaining pin to extend into the cylinder housing.
   
2. Rotate the lock cylinder using the lock cylinder key, to ensure correct mechanical operation in all positions.
   
3. Connect the negative battery cable.
   

Non-Functional Lock
The following procedure applies to vehicles in which the ignition lock is inoperative and the lock cylinder cannot be rotated due to a lost or broken key, unknown key number or a lock cylinder cap that has been damaged and/or broken to the extent that the lock cylinder cannot be rotated.

I have 07 Pontiac Grand Prix, the wrong key was inserted into the ignition the other day. Now when I try to use the correct key it will not insert completly in the ignition, goes in until last 1/4in of key. Im stuck, I bought the new lock cylinder but how do I get the old one out? I cant get the key to insert all the way so I cant get it to the "On" position, it will not turn at all. The key that was inserted in error is whole and nothing is missing it seems like there is something stuck. Any help would be appreciated...

Ignition and Start Switch Replacement
Removal Procedure
Disconnect the battery ground cable. Refer to Battery Negative Cable Disconnect and Connect Procedure in Engine Electrical.
Remove the steering column filler panel. Refer to Steering Column Filler Replacement .
Remove the knee bolster bracket. Refer to Bracket Replacement - Knee Bolster .
Remove the instrument panel (I/P) cluster trim panel. Refer to Trim Plate Bezel Replacement - Instrument Panel (I/P) Cluster .
Remove the ignition switch bolts.
Lower the ignition switch away from the instrument carrier.
Insert the key into the ignition lock cylinder. Turn the key to the ON/RUN position.
Depress the transaxle park/lock cable retainer to release. Pull to remove the park/lock cable from the ignition switch.
Important: The Passlock? electrical connector cannot be removed until the lock cylinder is removed.

Depress and hold the detent on the bottom of the ignition switch in order to release the ignition lock cylinder. Remove the ignition lock cylinder with the key.
Disconnect the Passlock? electrical connector.
Disconnect the electrical connectors.
Important: Ignition switch lock cylinder that won't rotate or is seized.

Perform the following procedure if the ignition switch lock cylinder is seized or won't rotate.
12.1. Protect the immediate work area with suitable material such as clean shop towels or a clean fender cover.

12.2. Locate the surface for the ignition switch lock cylinder release button (2) on the plastic ignition switch housing and center punch a location (1) on the "rib" approximately 3/8 inch reward (toward the key entry end) from the cylinder release button.

12.3. Carefully drill a pilot hole through the plastic housing with a 1/8 inch drill bit.

12.4. Carefully drill a larger hole at the pilot location, and slightly into the ignition switch lock cylinder surface to break the release button retaining spring using a 9/32 inch drill bit.

12.5. Remove portions of the broken spring from the hole using a small suitable tool.

12.6. Grasp the ignition switch lock cylinder and remove it from the switch housing.

12.7. Remove any plastic "flash" from the drilling operation, and using compressed air blow out the ignition switch assembly.

12.8. Follow service manual procedures when cylinder cording is required. Refer to Key and Lock Cylinder Coding in General Information.

Installation Procedure
If the lock cylinder would not rotate or was seized, perform the following procedure:
1.1. Install the new ignition switch lock cylinder as required by rotating both the cylinder and the ignition switch to the ON position.

1.2. Push the ignition switch lock cylinder into the ignition switch housing until fully seated.

1.3. You may have to slightly depress the release button as the button passes by the 9/32-in hole previously drilled in the ignition switch housing.
Connect the electrical connectors.
Connect the Passlock? electrical connector.
Connect the park/lock cable to the ignition switch Turn the key to the ON/RUN position. Install the ignition lock cylinder into the ignition switch. If you turned the key slightly while removing the lock cylinder, you may have to align the white colored ignition switch rotor (1) with the lock cylinder (2). You can rotate the ignition switch rotor (1) with your finger.
Remove the key
Position the ignition switch to the instrument carrier.
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Install the ignition switch bolts.
Tighten

Tighten the bolts to 10 N?m (89 lb in).

Install the trim plate bezel to the I/P cluster. Refer to Trim Plate Bezel Replacement - Instrument Panel (I/P) Cluster .
Install the knee bolster bracket. Refer to Bracket Replacement - Knee Bolster .
Install the steering column filler panel. Refer to Steering Column Filler Replacement .
Connect the battery ground cable. Refer to Battery Negative Cable Disconnect and Connect Procedure in Engine Electrical.

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