Shoot me now!! My car alarm is going berserk again!!

<div class='quotetop'>QUOTE(msnancy61 @ Nov 13 2006, 08:52 AM) [snapback]348126[/snapback]</div>

At this point I'd guess that the "bad" battery was a side effect of another fault that has not yet been found. I expect the replacement battery will now turn out to be bad as well. At this point I'd want to put a ammeter on the 12V battery and see what kind of current drain is going on when it the car is supposed to be off.

I assume when the alarm kept going off, the battery wasn't down to the dead-as-a-doornail condition. There had to be some power available to make all that noise. Sorry to hear that the problem remains.

- Tom

 

as the Prius alarm system is tied into the pin switches for the interior lights it could possibly be that one of them is not adjusted right. That is about the only way to trigger the alarm, if they are properly adjusted the only other thing is the alarm module in the body computer. This could be a tough one to figure out so you best make friends with the Prius tech as the two of you will be in contact till your "Wacko" car is not doing it any more.

 

<div class='quotetop'>QUOTE(Frank Hudon @ Nov 13 2006, 10:30 AM) [snapback]348172[/snapback]</div>

We are assuming that you have the OEM car alarm activated, ....don't worry. Is Toyota's policy to correct ANY malfunction through its warranty period. Could be a hood pin mis adjusted or dirty as Frank mentioned before.

If you had a third party alarm installed by "others" including the dealer's recommendation equipment/installer the problem gets a tilt more involved, tilt/shock sensors mis adjusted or a bad CPU; anyway is beyond your control and take it to the dealer for corrections.

 

Were you in the habit of locking the car EVERY time you parked it? (I mean, back when you *could* lock it, before the battery/alarm went nuts.)

 

the visor lights are picky. they have to be switched on, and the visor has to be at a certain angle. kinda freaked me out at first too

 

According to the service manual, here are the items that will set off the alarm once it is armed:

Performing any of following will cause system
to "Alarm sounding state"
• Open any door and allow entry delay
time to elapse
• Open engine hood
• Reconnect battery
• Directly connect power switch without key
(or push power switch ON without key)



The last two seem particularly interesting in your situation. If there is an intermittent battery connection or flakey battery and the voltage drops for a short time while the alarm is armed, when the voltage comes back the alarm will go off.

Also, if there is an intermittent short in the power switch or power switch circuit and the power circuit is triggered with the alarm armed, that will also set off the alarm.

Of course, if any of the door or hood switches close it will also trigger the alarm, and in addition, if you have the optional glass breakage sensor it could be set too sensitive and be getting false triggers.

This is the hardest type of fault to trace because it is clearly very intermittent. If you've noticed any other symptoms, it might be easier to diagnose. Have you ever noticed a dome light coming on for no reason? How about the open door warning light coming on while driving?

Best of luck on this one.

 

Have you considered putting a video camera on the car during the night, just to see if anything weird is happening? I know someone that was driven nearly nuts by a monkey that would set off the perimeter alarm at their base. Each time they had to respond with a patrol. There was nothing wrong with the alarm, just a problem with a monkey. I suspect you don't have monkeys in your neighborhood, but maybe something else is happening late at night.

Tom

 

<div class='quotetop'>QUOTE(msnancy61 @ Nov 18 2006, 11:01 AM) [snapback]351373[/snapback]</div>

Cell phones kick out quite a bit of interference. You can hear them if you leave one close to your computer. Every once in a while it will respond to a poll from the cell tower and the computer's speakers will go "da da da, da da da, da da da". It will always be the same little cluster of sounds. The electronics in the Prius should be pretty well shielded, but stranger things have happened.

Tom

 

makes me wonder if there's something at your house that's causing it... since it didn't happen at the dealership. hmm...

 

Galaxee's response got me to thinking and someone a couple of years ago had the same problem at a particular store they used to go to. It turned out to be the stores door opening system. I recall it only happened in one area of the parking lot. This went back to about May or June of 2004 but that was before the first crash on PC. Data long gone. Not saying that is the cause of this incident but it's possible. So next question does this happen only when it's in your garage or if you park it at a park or in a lot somewhere does it do it there as well?

 

you said that you store the car in your garage, do you have an alarm system installed at your house and a motion sensor installed there to?. Some sensors do emit a HI frequency able to trigger or interfere with garage door openers receivers and wireless systems nearby, not complying with FCC regulations

 

This is getting way weird!

Probably not connected, but a few weeks ago, I was in town with my cousins, shopping...I had my smart key in my pocket where I usually carry it...I was nowhere near my Prius.

There was a Prius in the lot of one of the stores...I went "Ooooh another Prius!"....walked toward the car and as I got within 10 feet or so, I heard the beep-beep you hear when you use the key to remote unlock the Prius...I used to unlock my car that way, before the smartkey setup.

I wanted to walk up and see if the doors opened but was afraid that someone would think I was trying to "break in." So, we just walked away.

Could my key have "unlocked" this other Prius remotely, even though I didn't touch my key, just came into range with the other Prius?

No one came out to the car, since we stayed around for a few minutes in case it was the owner who was approaching their car and had unlocked it.

Very weird. I also noticed now, that sometimes when I hit the power button only my radio comes on and sometimes a blank MFD...then I hit the Power button again and the car comes on...this, too, is intermittent.

I really hope to hear there is an answer to this alarm problem.

I worry about whether my cell phone could have an effect, since I do forget and leave it on in the car sometimes...not usually, but occasionally.

terri



<div class='quotetop'>QUOTE(Frank Hudon @ Nov 18 2006, 01:11 PM) [snapback]351416[/snapback]</div>

This does sound as though it's just this garage, doesn't it???

terri

 

starting to sound suspicous, I have to admit.

 

Have you tried unplugging everything in your garage including the garage door opener? ( Yeah I know a real PITA but you only have to do it for a day or two ) If not you may want to give that a try to rule out any thing in the garage that may be giving off some bad RF. You may want to go as far as flipping the switch on your circuit breaker if you garage has a separate circuit.

There are only 3 things that I can think of that would set off the alarm only at your place.

1. Bad RF in your garage or maybe a neighbor has a high power radio transmitter that somehow is setting off the alarm.

2. You have the glass breakage sensor and you have something like a high pitched noise that goes off and sets off the alarm. Something like an electronic mosquito repeller.

3. You have boogie men in your garage and your Prius gets scared. In this case get it a night light.

I'm out of ideas.