2019 Corolla Sports Tourer Alarm issue

[tadcad]

Hi,

I own a 2019 Corolla Touring Sports 1.8 Hybrid and over the current cold spell have had issues with the alarm going off randomly in the early hours.  I noticed on the 2 occasions I was woken up with, There was a hard frost/ice on the windscreen, so I believe it has something to do with the ice. I read somewhere there is a hood sensor under the bonnet which sometimes may get water in it and if it freezes, expands and sets the alarm off.  I have had to leave the car unlocked, which isn't ideal.

Dealer wants to charge £60 to do a diagnostic but I am not sure that will show anything. I did was the car prior to this occurring, so I am wondering if the hood sensor info is possible?  Any thoughts on here fellow Toyota owners?

 

Cheers

[Gerg]

These are front and back pictures of an Auris bonnet lock.  I would expect a Corolla one to look quite similar.  The area of the switch that you refer to is highlighted with the red arrow.  If you could spray in that general area with you moisture repellent of choice (WD40 etc.), then that might do what you were wishing to do.  The first red arrow is pointing at the connector of the switch, next to the switch.

The wires to this switch seem to have been cut by the vehicle breaker.

Close up the switch will look a little bit like this one, but without the three electrical connectors sticking out.

You are probably aware that the ultrasonic portion of the alarm can be temporarily disabled via a button that is (likely) on the 'B' pillar?  This is used for if you have to leave a dog or suchlike in the car.  The function resets to operating normally on the next unlock/lock cycle.  

Toyota don't supply a complete paper owner's manual for some years now, but a full manual can be downloaded for free from the Toyota GB website.  More alarm details might be in included in that.

Did the dealer explain what the diagnostic was that they were going to do?

HTH

[Sidrat]

On 1/21/2020 at 7:45 PM, tadcad said:

Hi,

I own a 2019 Corolla Touring Sports 1.8 Hybrid and over the current cold spell have had issues with the alarm going off randomly in the early hours.  I noticed on the 2 occasions I was woken up with, There was a hard frost/ice on the windscreen, so I believe it has something to do with the ice. I read somewhere there is a hood sensor under the bonnet which sometimes may get water in it and if it freezes, expands and sets the alarm off.  I have had to leave the car unlocked, which isn't ideal.

Dealer wants to charge £60 to do a diagnostic but I am not sure that will show anything. I did was the car prior to this occurring, so I am wondering if the hood sensor info is possible?  Any thoughts on here fellow Toyota owners?

 

Cheers

The dealer should not be charging anything, your car has a fault that is covered by the warranty, on what grounds are they making a charge for a fault!  I notice you are in Norfolk (snap), which dealership is it?

[Cjohnston1982]

32 minutes ago, Sidrat said:

The dealer should not be charging anything, your car has a fault that is covered by the warranty, on what grounds are they making a charge for a fault!  I notice you are in Norfolk (snap), which dealership is it?

Exactly! I’d contact Toyota GB and complain about the dealer wanting to charge £60

[FROSTYBALLS]

An increasing number of dealers, and not just Toyota dealers, will cover their costs by stating a diagnostic charge may be payable. If the fault turns out to be a warranty issue, the diagnostic charge isn't charged to the customer. If the fault is not a warranty issue, the charge is passed onto the customer.

The OP needs to clarify this with the dealer.

[Mike Cowieson]

I to have been having problems with my 2019 corolla sport tourer alarm going off in the evening, went out to the car after the alarm went off for the second time and when I opened the door there was a small insect (moth I think)flying about in the car, would this be enough to set off the alarm?

[FROSTYBALLS]

Possibly

[Catlover]

Couple weeks ago my Prius alarm set off a few times during the day on a couple days.  I couldn’t see anything obvious.  One night I had to leave car unlocked as I didn’t want to annoy neighbours. Couple days later I opened driver door and got in only to feel a cobweb around my head.  Alarm not blown off since. Must have been a spider that died off during the heat in the car during hot weather.

[Velvet--Glove]

13 hours ago, Mike Cowieson said:

I to have been having problems with my 2019 corolla sport tourer alarm going off in the evening, went out to the car after the alarm went off for the second time and when I opened the door there was a small insect (moth I think)flying about in the car, would this be enough to set off the alarm?

Some time ago another member posted here about his car alarm going off randomly at night. He believed the culprit to be a moth trying to get to the street light outside. As far as I recall the moth was removed and the problem solved.

I have no proof one way or the other but I also suspect that a window left opened just a little bit can sometimes set the sensor off in windy conditions. I had an alarm problem whilst on holiday in 2019 and that was the only explanation I could come up with.

These alarms are a wee bit too sensitive if you ask me. 🙁

[Trewithy]

Would turning off the ultrasonic part of the alarm reduce the drain on the Battery when parked?