Prius Alarm System - Any Known Problems ?

[kramaring]

I have owned an '06 Toyota Prius T3 since Oct 2006. I have been having an intermittant problem with the alarm system which hasn't recently gotten worse. The car alarm goes off for no reason at all when the car is sat on my drive

Sometimes it is a one off - other times like last night it happened three times :ffs:

The car has been back to the dealer on 4 occassions. They eventually changed some alarm sensor but the problem has if anything gotten worse since then. My confidence in the dealer is now zero.

I wonder if any other Prius owners have had any alarm problems. If so what were they and how were they fixed ?

Any idea if it is possible to deactivate permanently or remove the audible part of the alarm system in a Prius.

Final question - When I get out of the Prius and lock the doors / activate the alarm with the key fob - I notice that the alarm indicator light (a red light with a key symbol) pulses rather that blinks on and off. I think the manual states that the light should blink on and off whereas mines stays permanently lit but pulses in brightness. Can anyone confirm whether this is normal - i.e what does the alarm indicator light do on your prius when you lock the car.

Yours - one unhappy Prius owner.

[SilverT4]

I have had my Prius now fro over three years and never had any alarm problems. However I was sat in my Toyota dealers service waiting area the other day and overheard a conversation between the receptionist and a customer.

The customer had been complaining for some time about his alarm activating whislt the car was on his drive, but it had been checked over by the dealer who could find no problem. It then transpired that one of his neighbours was setting off the alarm when he used his remote key fob on his own car (not sure if it was also a Toyota). The receptionist thought they must be using the same radio frequency and she would have to speak to Toyota to find out how to change it as there is no field change procedure for this.

Maybe you have the same problem?

[ak56]

This has just started to happen with our Prius alarm. It went off a few times during the day, a few days ago. It was then OK for a few days and started to go off intermittantly again this morning. Fortunately it has not gone off at night.

I will check with the neighbours to see if they are doing anything different, given comments in last post.

I am trying to contact the dealer by phone with no luck yet (they are always v busy!!) to see what they suggest.

[Lye]

Had my Prius Spirit Nov 07, Alarm has been playing up going off at night and unable to open the car other than with the key and of course the alarm goes off. The time clock also reverts to 1pm so it appeared to be a power cut.

Local dealer sorted it out, a bad earth, no trouble since.

[ak56]

I found my sunglasses in the overhead storage were kinda jammed up against the roof space. I read somewhere the sensor for the internal alarm is up there somewhere. I removed the sunglasses.

Since then no more intemitant alarm activations! Not sure if this solution has any serious credibility, but if anyone is having problems with the alarm its an easy thing to try.

[petrolhead]

if you arm the alarm them wave your hand abone the front of the roof area and the alarm goes off it is because the sensor is going the wrong way out of the car there is a toyota fix i think it is to tape over the top of the sensor above the front map light

[kramaring]

This problem was fixed a while ago but I never posted up

It was caused by my sunglasses being stored in the overhead compartment. Once I removed my sunglasses from the compartment, which I assume is meant for sunglasses. The problem went away.

Strange but true.

[Mkuk0]

This problem was fixed a while ago but I never posted up

It was caused by my sunglasses being stored in the overhead compartment. Once I removed my sunglasses from the compartment, which I assume is meant for sunglasses. The problem went away.

Strange but true.

How did you discover this? was it the earlier post? or Did Mr T pass on info? If so, what reason did they give for sunglasses in holder causing alarm to go off? I am intrigued.

[stompe]

The alarm problem could possibly be when taxi's speak on their radio I have known it to set off car alarms. Not being an engineer I think the problem somehow interfers with the Prius' ultra sonics, i.e. the alarm button down by your knees. I think if you turn it off and give it a try, it might not set off your alarm (this is only the ultra sonics it turns off not the whole alarm). I know this is not really the answer but I think it may work.

Stompe

[gammydad]

My new Prius set its alarm off three times - once in the eveing and twice in the morning.

To the best of my knowledge none of the neighbours was using their car door remote key at the time, and there were no taxis in the area.

I did have a purse contaning parking meter coins in the small overhead 'sunglasses bin'. I have since removed the purse (and yes there is a sensor inside this little bin) and, several days later, there have been no more incidents.

So, maybe the sensor is sensitive to metal objects in the bin.

[Barb in the OC]

My new Prius set its alarm off three times - once in the eveing and twice in the morning.

To the best of my knowledge none of the neighbours was using their car door remote key at the time, and there were no taxis in the area.

I did have a purse contaning parking meter coins in the small overhead 'sunglasses bin'. I have since removed the purse (and yes there is a sensor inside this little bin) and, several days later, there have been no more incidents.

So, maybe the sensor is sensitive to metal objects in the bin.

I came home from work tonight and couldn't lock the car because, after a few seconds, the alarm would go off. I checked online, found this post, removed my sunglasses from the little overhead bin, and the alarm has stopped going off.

Thanks for posting this. It would have been a long night.

[Mike Nelson]

The only problem I have had with the Prius alarm going off unexpectedly (3 nights in a row) turned out to be a large moth stuck in the car that came out at night and headed for the full moon.. on the 3rd night we discovered what it was and since then nothing!

perhaps you should look out for trapped moths!!

that said I did in once car park have a problem with the car not locking or unlocking with the remote but so did 3 other drivers nearby - until the police arrived and arrested 3 shady characters in a nearby car apparently they were using doorbell remotes to block the keytag signals. so could this be an issue

[geeno]

We have an 06 Prius, too, and never had any problem with the alarm system until in Colorado last week. It was parked in front of our vacation home in Estes Park, and for four nights in a row, the alarm came on. One night it came on four times. There are no sunglasses or anything else in the top compartment, so... Anyway, once we left Estes Park, there was no malfunction at our motel in New Mexico, and have been none since our return. Could some radio alarm up there have set this off?

[Chris Dance]

geeno. It is almost certain you were in the vicinity of a radio mast. I had this when I visited friends in Essex. I had an Avensis when it happened to me.We found out others in the area were having alarm system problems. It was found the mast owners had increased the signal strengh. After many complaints they reduced the signal strength and no more problems.

In my home area never had any problems.

[peaches76]

I have owned an '06 Toyota Prius T3 since Oct 2006. I have been having an intermittant problem with the alarm system which hasn't recently gotten worse. The car alarm goes off for no reason at all when the car is sat on my drive

Sometimes it is a one off - other times like last night it happened three times :ffs:

The car has been back to the dealer on 4 occassions. They eventually changed some alarm sensor but the problem has if anything gotten worse since then. My confidence in the dealer is now zero.

I wonder if any other Prius owners have had any alarm problems. If so what were they and how were they fixed ?

Any idea if it is possible to deactivate permanently or remove the audible part of the alarm system in a Prius.

Final question - When I get out of the Prius and lock the doors / activate the alarm with the key fob - I notice that the alarm indicator light (a red light with a key symbol) pulses rather that blinks on and off. I think the manual states that the light should blink on and off whereas mines stays permanently lit but pulses in brightness. Can anyone confirm whether this is normal - i.e what does the alarm indicator light do on your prius when you lock the car.

Yours - one unhappy Prius owner.

Also check how close your car is to the Kitchen as our alarm goes of when I park at my Mums and she puts the microwave on (about a foot and a half apart - albeit with an external wall).

[stompe]

While my car was in for repair, my dealer loaned me a brand new Prius. I noticed on the sunglasses holder a small round sticker which said "please do not put any metal objects in the holder". This sticker was not on my 2006 Prius T-Spirit so I assume that Toyota are aware of this problem. Hope this helps.

Stompe

[jvan]

My new Prius set its alarm off three times - once in the eveing and twice in the morning.

To the best of my knowledge none of the neighbours was using their car door remote key at the time, and there were no taxis in the area.

I did have a purse contaning parking meter coins in the small overhead 'sunglasses bin'. I have since removed the purse (and yes there is a sensor inside this little bin) and, several days later, there have been no more incidents.

So, maybe the sensor is sensitive to metal objects in the bin.

I also put some parking change in the overhead sunglasses compartment - and subsequently had intermittent alarm activations - I removed the change and have had no more problems. Thanks for this.

[georgeinstrell]

My new Prius has random alarm problems and remote sometimes does not open the door.

has anyone ever had this fixed

[Mkuk0]

Does it always happen when you park in the same place? Interference from Mobile phone masts etc can stop the remotes working.

[georgeinstrell]

Does it always happen when you park in the same place? Interference from Mobile phone masts etc can stop the remotes working.

No it occurs in different places. The unlock problem only occurred once, but the alarm problem occurs in different places and 2 or 3 times a week.

I have removed my sunglasses from the box and for 2 days it has not occurred.

[mamalilicula]

Here's a good one for you.

My wife and I regularly park a Toyota Celica (2004) and a Toyota Prius (2007) side by side outside our house.

We came home in the Prius earlier this evening and about half an hour later the alarm on the Celica started off for no reason. I cancelled it, but it then randomly started off at 5 to 15 minute intervals. Then the alarms on both cars would set off randomly! All very strange! I checked on various forums, including this one, and checked that the service batteries were fine (12.47V and 12.40V). I then removed one item from the Prius and the Celica was then quiet, but the car alarm on the Prius continued to set off more frequently at intervals of only a few minutes. I then removed a second item from the Prius and all has been quiet ever since.

The answer? We had left 2 mobile phones in the Prius, and these were the items I removed 1 at a time. Neither of them had received any messages or calls during this time, it was just their presence interfering with the alarm systems on both cars, just as they interfere when placed close to an AM radio. Please don't ask why we left 2 mobile phones in the Prius!

I hope this may help others with random car alarms being triggered.

[Franchise_mark]

We too have had problems with the Prius alarm going off from time to time. After reading through posts on this site and others, it turned out to be my Kindle Fire HD. Either the Wi-Fi or the bluetooth set of the alarm if left in the car.

[Toyota 2006 alarm]

For the past 1 1/2 year our 2006 Prius, Alarm is going off randomly at night and waking everyone up :(

- nothing is in the overhead sunglass holder.

- tried not locking doors, this doesn't help

- had the Battery checked

- switched FOB's - don't think that's it, car is parked far away from apartment

Does anyone know how to unplug the alarm?

[PeteB]

2 hours ago, Toyota 2006 alarm said:

...

- tried not locking doors, this doesn't help...

Now that's really odd - the alarm should only be set by the remote key locking the car, so locking with the emergency key or not locking at all should leave the alarm fully off (unless there's an odd spec for your part of the world).

That suggests to me there's a fault somewhere.

There is a button somewhere that if pressed within 20-30 sec of powering the car off disables the ultrasonic part of the alarm, might help - I think it's somewhere near the steering column on the Gen 2.

One place to try is a search on Priuschat, although many here have extensive knowledge and may have some ideas.

Have you checked your manual to see if it's protected by a fuse that only covers the alarm, in which case pulling ti out may help?

[Akashoops]

I had similar issue with my Prius 08 Tspirit. 

I found following reasons for the alarm to be activated:

1. Any mobile phone left inside car. Anywhere in front.

2. Any laptops or PDA left in car.

3. Any messing around with alarm or radio system. E.g. aftermarket stereo system, after market alarm system. 

If no device left in car alarm doesn't come on. I haven't had issue with sunglass holder yet.