Key will not unlock door

LOCKING AND UNLOCKING
You can use the power door lock control or the remote control to lock and unlock your doors and tailgate.See Tailgate Lock.
Power Door Locks
The power door lock control is on the driver and front passenger door panels.

AUnlock.
BLock. Remote Control
You can use the remote control at any time your vehicle is not running.
Unlocking the Vehicle (Two-Stage Unlock)
Press the button to unlock the driver door. Press the button again within three seconds to unlock all doors.The direction indicators flash. The direction indicators flash twice to confirm the change. The unlocking mode applies to the remote control, keyless entry keypad and intelligent access.
Press and hold both the lock and unlock buttons on the remote control for four seconds to disable or enable two-stage unlocking. Disabling two-stage unlocking allows your entire vehicle to unlock with one press of the button.
Intelligent access at the driver door unlocks your entire vehicle when you disable two-stage unlocking.
Locking the Vehicle
Press the button to lock all doors.The direction indicators flash.
Press the button again within three seconds to confirm that all the doors are closed.The doors lock again, the horn sounds and the direction indicators flash if all the doors are closed.
Mislock
If any door is open, or if the hood is open on vehicles with an anti-theft alarm or remote start, the horn sounds twice and the direction indicators do not flash.
Activating Intelligent Access
General Information
You can unlock and lock the vehicle without taking the keys out of your pocket or purse when your intelligent access key is within 3 ft (1 m) of your vehicle. Intelligent access uses a sensor on the back of the door handle for unlocking and a separate sensor on the face of each door handle for locking.
The system does not function if:

• Your vehicle battery has no charge.
• The key battery has no charge.
• The key frequencies are jammed.

Note: The system may not function if the key is close to metal objects or electronic devices, for example keys or a cell phone.
Note: If the system does not function, use the key blade to lock and unlock your vehicle. See Remote Control.
Unlocking Using Intelligent Access
With your intelligent access key within 3 ft (1 m) of your vehicle, touch the unlock sensor on the back of the door handle for a brief period and then pull on the door handle to unlock, being careful to not touch the lock sensor at the same time or pulling the door handle too quickly. The intelligent access system requires a brief delay to authenticate your intelligent access key fob.
Locking Using Intelligent Access
With your intelligent access key within 3 ft (1 m) of your vehicle, touch the outer door handle lock sensor for approximately one second to lock, being careful to not touch the unlock sensor on the back of the door handle at the same time. After locking, you can immediately pull on the door handle to confirm locking occurred without inadvertently unlocking.
Note: Do not use the outside door handle as a roof cargo strap.
At the Electronic Tailgate (If Equipped)
Press the exterior tailgate release button inside of the tailgate handle. The tailgate unlocks and opens. See Electronic Tailgate.
Smart Unlock
This feature helps to prevent you from locking your intelligent access key inside your vehicle's passenger compartment or rear cargo area.
If you leave your key in the ignition, when you open the driver door and lock your vehicle with the power door lock control, the doors lock then unlock.
You can still lock your vehicle with the key in the ignition by:

• Using the manual lock on the inside of the door.
• Locking the driver door with a key.
• Using the keyless entry keypad.
• Using the lock button on the remote control.

Smart Unlocks for Intelligent Access Keys
This feature helps to prevent you from locking your intelligent access key inside your vehicle's passenger compartment or rear cargo area.
When you lock your vehicle using the power door lock control (with the door open, vehicle in park and ignition off), your vehicle searches for an intelligent access key in the passenger compartment after you close the door. If your vehicle finds a key, all of the doors immediately unlock.
In order to override the smart unlock feature and intentionally lock the intelligent access key inside your vehicle, you can lock your vehicle after all doors are closed by using the keyless entry keypad, pressing the lock button on another intelligent access key or touching the locking area on the handle with another intelligent access key in your hand.
When you open one of the front doors and lock your vehicle using the power door lock control, all doors lock then unlock if the ignition is on.
Autolock
Autolock locks all the doors when:

• All doors are closed.
• The ignition is on.
• You shift into any gear putting your vehicle in motion.
• Your vehicle reaches a speed greater than 12 mph (20 km/h).

Autolock repeats when:

• You open then close any door while the ignition is on and your vehicle speed is 9 mph (15 km/h) or lower.
• Your vehicle reaches a speed greater than 12 mph (20 km/h).

Autounlock
Autounlock unlocks all the doors when:

• The ignition is on, all the doors are closed, and your vehicle has been moving at a speed greater than 12 mph (20 km/h).
• Your vehicle comes to a stop and you switch the ignition off or to the accessory position.
• You open the driver door within 10 minutes of switching the ignition off or to accessory.

Note: The doors do not autounlock if you electronically lock your vehicle after you switch the ignition off and before you open the driver door.
Enabling or Disabling Autounlock
You can enable or disable the autounlock feature in the information display or an authorized dealer can do it for you. See General Information.
Illuminated Entry
The interior lamps and select exterior lamps illuminate when you unlock the doors with the remote entry system.
The illuminated entry system turns off the lights if:

• The ignition is on.
• You press the remote control lock button.
• After 25 seconds of illumination.

The dome lamp does not turn on if the control is set to the off position.
The lights do not turn off if:

• You switch them on with the dimmer control.
• Any door is open.

Battery Saver
The battery saver turns off the interior lamps 30 minutes after you switch off the ignition if a door is open and the dome lamp switch is on. It turns off the interior lamps after 10 minutes if the dome lamp switch is off.
Accessory Mode Battery Saver for Intelligent Access Keys (If Equipped)
If you leave the ignition on after leaving your vehicle, it turns off 15 minutes after you close all of the doors.

1. Close and lock all doors with the driver's side power lock / unlock switch located
on drivers door panel.

2. Insert key into ignition and remove it from the ignition key cylinder at least 6 times
within 10 seconds. Your hazard lamps will flash if you have performed this step
successfully. NOTE: Withdraw key completely from ignition cylinder each time. If
this procedure is performed to fast, system will not enter programming mode.

3. Insert key into ignition and turn to the ACC position.

4. Within 5 seconds, push ANY button oon the keyless remote. Your hazard lamps
will flash. NOTE: Do not press the button on the remote more than one time or the
programming will not be successful.

5. If there are any remaining remotes (including old ones), Unlock then Lock all doors
using switch on drivers door panel and within 5 seconds press ANY button on the next
remote. Your hazard lamps will flash. Repeat this step for each remote (including any
existing remotes).

6. Turn key to the off position, remove key from the ignition. Unlock door using switch on
door panel and open drivers door.

7. Test remote(s).

Free Nissan Keyless Remote Programming Replacement Key Keyfob Maxima...

2004 Nissan Maxima Key Fob Programming Instructions

2004 Maxima

IMPORTANT: Before entering programming mode, have in possession all of the transmitters you will be using on the vehicle. Once you program the transmitter, all previous codes will be erased from the memory. The other transmitters will not be functional until you program the transmitters again.

1. Close and lock all doors with the driver's side power lock/unlock switch.
2. Insert key into ignition and remove it from the ignition key cylinder at least six times within 10 seconds. Your Hazard Lamps will flash if you have performed this step successfully. NOTE: Withdraw key completely from ignition cylinder each time. If this procedure is performed too fast, system will not enter programming mode.
3. Insert key into the ignition cylinder and turn to the ACC position.
4. Within 5 seconds, push ANY button on the remote transmitter. Your Hazard Lamps should flash. NOTE: Do not press the button more than one time in the above step. If the button is pressed more than one time, the programming procedure will not be successful.
5. If there are any remaining transmitters (including the old ones), unlock then lock all doors using the driver's side power lock/unlock switch and within 5 seconds, push ANY button on the next remote. Your Hazard Lamps should flash. Repeat this step for each transmitter (including any existing transmitters).
6. Turn the key to the OFF position, remove keys from the ignition,
   unlock doors using the driver's side power lock/unlock switch and open the driver side door.

You may need to program it. Here is how you do that, if that is not a fix then you may need a new remote.

1. Remove key from ignition.
   
2. Close all doors.
   
3. Open driver side door and leave open.
   
4. Perform the following steps within 24 seconds.
   a. Insert key in ignition.
   b. Turn key to ON and OFF.
   c. Repeat step b two more times.
   d. Remove key.
   e. Push driver door frame button three times (black rubber button located on driver door frame that tell the vehicle whether or not door is closed.)

5. Buzz sound, chime or doors will lock and unlock should be heard at this point signaling that the vehicle is now in
programming mode. If not, wait 40 seconds and return to step 4.

6. All transmitters need to be programmed at this time, including the old ones. Push any button on the transmitter
two times. A buzz sound, chime or doors locking and unlocking should be heard at this point signaling that the
vehicle has accepted the new transmitter code. If there is only one transmitter, repeat this step two more times
using the only transmitter. If there are two transmitters, repeat this step two more times using the second
transmitter.

7. Push driver door frame button one time. Two buzz sounds, chimes or doors locking and unlocking 2 times should
be heard at this point signaling successful programming.

IMPORTANT: Before entering programming mode, have in possession all of the transmitters you will be using on the vehicle. Once you program the transmitter, all previous codes will be erased from the memory. The other transmitters will not be functional until you program the transmitters again.
1. Close and lock all doors with the driver's side power lock/unlock switch.

2. Insert key into ignition and remove it from the ignition key cylinder at least six times within 10 seconds. Your Hazard
Lamps will flash if you have performed this step successfully. NOTE: Withdraw key completely from ignition cylinder
each time. If this procedure is performed too fast, system will not enter programming mode.

3. Insert key into the ignition cylinder and turn to the ACC position.

4. Within 5 seconds, push ANY button on the remote transmitter. Your Hazard Lamps should flash. NOTE: Do not press
the button more than one time in the above step. If the button is pressed more than one time, the programming
procedure will not be successful.

5. If there are any remaining transmitters (including the old ones), unlock then lock all doors using the driver's side
power lock/unlock switch and within 5 seconds, push ANY button on the next remote. Your Hazard Lamps should
flash. Repeat this step for each transmitter (including any existing transmitters).

6. Turn the key to the OFF position, remove keys from the ignition, unlock doors using the driver's side power lock/unlock switch and open the driver side door.

Ok here are the programming instructions for the remote, follow them exactly, no missed steps, if this doesn't correct the issue the remote is defective most likely.

1. Remove key from ignition.
   
2. Close all doors.
   
3. Open driver side door and leave open.
   
4. Perform the following steps within 24 seconds.
   a. Insert key in ignition.
   b. Turn key to ON and OFF.
   c. Repeat step b two more times.
   d. Remove key.
   e. Push driver door frame button three times (black rubber button located on driver door frame that tell the vehicle whether or not door is closed.)

5. Buzz sound, chime or doors will lock and unlock should be heard at this point signaling that the vehicle is now in
programming mode. If not, wait 40 seconds and return to step 4.

6. All transmitters need to be programmed at this time, including the old ones. Push any button on the transmitter
two times. A buzz sound, chime or doors locking and unlocking should be heard at this point signaling that the
vehicle has accepted the new transmitter code. If there is only one transmitter, repeat this step two more times
using the only transmitter. If there are two transmitters, repeat this step two more times using the second
transmitter.

7. Push driver door frame button one time. Two buzz sounds, chimes or doors locking and unlocking 2 times should
be heard at this point signaling successful programming.

Open the remotes up...Are the boards the same...?

IMPORTANT: Before entering programming mode, have in possession all of the
transmitters you will be using on the vehicle. Once you program the
transmitter, all previous codes will be erased from the memory. The other
transmitters will not be functional until you program the transmitters
again.

1. Close and lock all doors with the driver's side power lock/unlock
switch.

2. Insert key into ignition and remove it from the ignition key cylinder
at least six times within 10 seconds. Your Hazard
Lamps will flash if you have performed this step successfully. NOTE:
Withdraw key completely from ignition cylinder
each time. If this procedure is performed too fast, system will not
enter programming mode.

3. Insert key into the ignition cylinder and turn to the ACC position.

4. Within 5 seconds, push ANY button on the remote transmitter. Your
Hazard Lamps should flash. NOTE: Do not press
the button more than one time in the above step. If the button is
pressed more than one time, the programming
procedure will not be successful.

5. If there are any remaining transmitters (including the old ones),
unlock then lock all doors using the driver's side
power lock/unlock switch and within 5 seconds, push ANY button on the
next remote. Your Hazard Lamps should
flash. Repeat this step for each transmitter (including any existing
transmitters).

6. Turn the key to the OFF position, remove keys from the ignition, unlock
doors using the driver's side power lock/unlock switch and open the driver
side door.

Courtesy of: forums.mazdaworld.org

Try this, it works on several 2002 models:


Step 1: Open drivers door and leave open.

Step 2: Lock and unlock the drivers door using the power door lock switch on the door.

Step 3: Insert key into the ignition.

Step 4: Turn key to on position and return to off position. (IMPORTANT - use ON position NOT ACC position). Do this 3 times within 10 seconds. Leave key in the ignition.

Step 5: Open and close the drivers door 3 times. (Door should be left open after this step).

Step 6: ECU should respond by locking and unlocking the doors.

Step 7: Press any button on remote #1. ECU responds by locking and unlocking the car doors.

Step 8: Press any button on remote #2 (etc.) Each time the ECU will respond by locking & unlocking the doors.

Step 9: Remove the key from the ignition and the ECU will respond a final time with a series of door locks and unlocks. You're done

Close all vehicle doors, LOCK doors using drivers side switch.

Insert key all the way into the ignition, (do not turn) remove key.

Repeat this step 5 times. (6 total)

Hazards should flash to indicate program mode.

Press any button on transmitter to be programmed, hazards should flash to indicate successfull program.

*For additional remotes, cycle drivers door lock UNLOCK, LOCK, press any button on remote, hazards should flash. Repeat step as necessary.

Ignition ON, (engine off) ignition OFF, UNLOCK using drivers side switch, test remotes.

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