My alarm!!

[B_Tank88]

The alarm has recently been going off randomly, annoying neighbours and myself. Woke me up at 1am yesterday in the freezing cold.

I have used that toyota manual to do the door dance to find out what was the last alarm trigger:

https://www.toyota-tech.eu/aimuploads/%7B1B61A262-6063-4E19-80F5-01ABC951B6F6%7D/TVSS%20setting%20guide%20for%20TVSS%20IV-S%20%20LHD%20T4SLSET-2-0-F.pdf

Page 18

Everytime, I get 5 indicator flashes, which suggests bonnet switch.

I have taken the bonnet switch out (yes, completely out and in my hand). Alarm still went off that night.

Another test showed same 5 indicator flashes, saying bonnet switch. I now took the boot switch (engine cover) one out just in case.

Still alarm is going off.

I've taken the buzzer out from the frunk, but internally the alarm is still going off with indicator flashes!

What else could it be??? Interior radar? Glass breakage sensors? That's not what the indicator flashes say!

[Carolyn]

I took the siren out of mine.  Nobody reacts to them anyway. More trouble than they are worth.

[B_Tank88]

Yep I've taken the siren out of mine too, but the alarm itself still triggers and means indicators flash. Not as big of a deal anymore as it makes no noise but worried about battery drain.

[fawtytoo]

but worried about battery drain

If my Smart fortwo was anything to go by:

I found it one morning with a completely flat battery. I couldn't even unlock the doors as they're fully electronic. Eventually I managed to get the passenger door to unlock and, upon opening it, the alarm went off. Good and proper too for about 15 minutes whilst trying to jump start the car from the MR2.

I'm thinking alarms have their own batteries that are recharged from the car battery. But on a 20ish year old car (such as our MR2's are), the alarm battery may not be holding a very good charge anymore, and the indicator flashes are no longer reliable as to what the reason is.

If it makes you feel any better, my MR2 will periodically sound the alarm and gives the same indicator flashes on testing it. But, the more I drive it, the less likely it happens.

EDIT: Incidentally, I left my alarm intact rather than disconnect the siren as that's how the car is insured.

[Beachbum957]

The alarm uses a motion sensor, but almost anything sets it off.  A leaf floating by with the top down, or slight gust of wind moving a window with the top up, or well, almost anything.  Both useless and annoying.

The sensitivity supposedly can be set, but you can also turn it off, which is what we did on a 2003.

This link should have the instructions.

The system does connect to the regular battery, and will run the battery down if the car sits long enough (weeks).

[virginpaul]

If the alarm tells you it's a particular switch, it doesn't know if it's the switch or the wire from the alarm unit to it that's going to ground, so removing just the switch may mean the switch is ok, but the wire to it might have an intermittent earth (nicked or sheath damage)....