Car alarm goes off whilst locked

You need to have the alarm module scanned by the dealer.

To remove the shift knob on a 2002 Toyota Celica GT just turn it rather hard counter-clockwise while in neutral. To remove the shift boot, it's easier to remove the carpet. There's a few screws that are under the carpet, remove them, then you can take out the boot.-----------------------------------------------------------------------------
BENZ STAR C3 Super Mb star updated by internet 2012.11 Fit all computer

The steering lock may be binding the ignition lock cyl preventing the key from turning or the key may be worn out. Try turning the steering wheel back and forth while wiggling and turning the ignition key. To get the alarm to turn off without starting the car try locking and unlocking the vehicle from the passenger side door. There is a micro switch on the drivers side door lock cyl that may be bad and preventing the alarm from dis arming. This is all providing it is a toyota factory alarm sys.

You have an aftermarket alarm in it? tear it out.

alloy wheels

Wheel Part Number: #69387
2000-2005 Toyota Celica
Size: 15" x 6.5", 5 Lug, 100mm Bolt Pattern
Finish: Silver
Description: 5 Double Spoke OEM Alloy Rims

steel wheels

Wheel Part Number: #69386
2000-2005 Toyota Celica
Size: 15" x 6.5", 5 Lug, 100mm Bolt Pattern
Finish: Black
Description: 12 Hole Original Steel Rim

It shouldn't do it, that's for certain. The cause is usually a failed central locking door solenoid; to replace it requires that the fault is first correctly diagnosed using a bit of experience and common sense and that the inside of the affected door is removed to access the faulty part.

All of this can either be done by an auto-electrician or a competent repair garage. It's also possible on a DIY basis using a repair manual if your son already has a reasonable tool set, a practical mind and a bit of patience. Unfortunately the main publisher, Haynes, don't cover the 2000-onwards Celica, but I've just found a webpage which claims to offer a free download of a manual for the vehicle. Note that using the downloaded file requires a password which the website shows beneath the links to the manual. No harm in trying!

I hope that I've been of some assistance and that you soon regain your morning lay-ins! Please take a moment to rate my answer.

it could be the door lock acuator going bad it could have a intermittent short

I looked under the seat and there was not a small box with 3 wiring connections on it. Any other thoughts?

Not really a solution, sorry. But, my 93 celica had the same problems as your having now. Mine just worked when it wanted to. I had to end up having someone check it out. They basically said "Who the hell hooked up your alarm?" I have no clue, I figured it came like that, but I guess someone took it out and redid it. That may be your problem. Unhook your alarm or take it in and just ask someone.

Do you have a sound system? Most...as my previous owned did, like to somehow hook the sound system with the alarm. But of course when he sold me the car he took the system..leaving the alarm to go haywire.

Are you hearing any noises from the pass door when you activate the lock switch? If not, the power door lock solenoid has failed, and prob needs to be replaced. Pull the door panel & check to see if it is getting power to the solenoid in lock & unlock. If it has power, the solenoid is def bad.