Alarm goes off when opening the locked car with the key.

To arm content theft alarm.
1. Open the door.
2. Lock the door with the power door lock switch or
the remote keyless entry transmitter. The
SECURITY light should flash.
3. Close all doors. The SECURITY light should go off
after approximately 30 seconds. The alarm is not
armed until the SECURITY light goes off.

If a locked door is opened without the key or the remote keyless entry transmitter, the alarm will go off. The headlamps and parking lamps will flash for two minutes, and the horn will sound for 30 seconds, then will turn off to save the battery power.

If the dealer had change the part you sayd ask them to reset the ECU or the main computer off or car it should solve the problem

stop locking the door with the lock button while the door is open. That engages the factory alarm. You can also use the key in the driver door lock to disarm the system

Insert the key into the door lock on the driver side and move it to the unlock position two times quickly. That should turn off the alarm.

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their is no doubt some way to reset it by turning the key so many times left and right ?? but try this ,and that put key in drivers side lock and lock and open three times slowly then open door on last attempt and try to start within 15 secs of opening the door lock ,also try the spare key in case the chip has fallen out of the key ??

open door. when alarm goes off put key in ignition and turn it on start car. this should disarm the factory alarm.

when the alarm goes off have you tried locking and unlocking the drivers door with the key sometimes that will turn the alarm off and allow you to start the car

Does it have remote central locking. If it does then it needs to be opened with the remote control. By opening the door with the key is the same as picking the lock to the alarm system so it put's on the alarm and imobilise's the car and actavates the alarm. Hope this help's Cheer's