97 avalon removed battery and tripped alarm car will not start

Anti theft system activated has to be reset with scan tool or key on 30 min off back on 30 min off back on 30 min off then start . need a battery charger hooked up powering battery for this method so it dosnt die and car will start. Also if you have remote keyless entry. Try driver window down and key on engine off doors all shut with remote lock car doors then reach in and open door ...does alarm sound? If so remove key from ignition (turn ignition off) close door put key in drivers door lock and turn key to lock door and then turn to unlock door ....alarm now off ? Then try to start car . also may have tripped the fuel cut off switch if equipped....look in trunk for shut off switch or kick panel passanger side front about where passanger feet would be the small trim panel under glove box also may need removed some where if your car is equipped you will find a black box about 4 inch tall by 3 inch wide and 2 inch thick with a round red button on top if you press this red button and feel it click then there is the problem ...fuel cut off is now reset try starting it again.

If the alarm system has a battery remove it otherwise removing the car battery for a while may reset it. In emergency contact your local toyota dealers mechanics department and they may be able to help you at no cost.
If you put a general enquiry on google you might get lucky, do not be too specific. i.e. toyota 1994 alarm reset procedure

Check if the two smaller wires on the starter motor next to the main supply cable are connected .If you short the two terminals on the front of the starter with a screw driver it should swing the engine and start it if the ignition is on this will also tell you if the battery has sufficient power in it to swing the engine. the alarm going off tells me those wires on the starter are not making good contact creating a short which could trigger the alarm.

Try having your battery checked. I had a new Lincoln which did the same thing. When the battery shorted, it would trigger the Alarm. This went on for a few weeks until diagnosed.

Have you locked and unlocked the driver door with the key ?

Same here... I have a 1998 Toyota Avalon XL. My car battery died. Replaced my car battery, but found out that when you unplug and plug the car battery with this car it engages in security mode (I have factory car alarm). This disables the engine and wont let you turn the ignition aka start the car engine until the remote (keyless entry) "UNLOCK" is applied. My remote is also lost so I cannot disable the alarm.
The only thing I can think of to do is unplug the battery again to disable everything (car alarms are annoying...) and call the dealer to pick the car up and perform the diagnosis. Most likely they will offer you another keyless (ugh... expensive) and/or you could ask to disable the factory car alarm.
I know thats not much help but it seems to be the only option from what I researched currently....

There is a good possibility that your battery is shorting out. The alarm can trigger when it detects tampering which can be when someone tries to jump the alarm or starter. The battery cables can also be dirty which can also cause the current to interrupt. The alarm is suppose to cut off the power to the starter or ignition. If the engine still turns over the problem could just be the battery.

I had a new 1988 Lincoln with a bad battery and the alarm would activate on its own.

Sound like you have a bad alternator, poss bad battery too.If you can jump start it with a volt meter check voltage at battery should have above 13.5 volts, do this after you unhook jumper cables and engine running.If bad voltage reading replace alternator make sure you charge battery before starting engine with new alternator or it could damage alternator.If good voltage have battery check.Hope this helped.

It won't crank? Does the alarm system works? Like locking and unlocking the doors? If that work, check cranking voltage to starter solenoid with a test light. But before, check all fuses under dash and hood. Make sure battery connections are clean and tight. There is more but try this for now. Let me know of the solenoid test and please ask any questions.

You need to first look under the drivers side dash area near the hood release/fuse panel area and see if there is a valet switch. The switch will look like a little toggle or a push switch. After you locate it, turn the ignition switch to the on position(dont start it) and flick the valet to the opposite position it is in now. If done correctly in most cases the red system light will stay a constant instead of off or blinking indicating you are in valet mode. Next try to start the engine. If this doesnt work you need to remove the alarm system and repair the ignition switch wiring or replace the electrical portion of the ignition switch. The aftermarket alarm cuts into the ignition switch wires and bypasses the start circuit through the alarm module. When disarmed the alarm completes the circuit and allows the car to start. Good luck hope this helps and please rate this.