Alarm Sounding randomly? 2015 Rav 4

[Sioo7]

I have a 2015 Rav 4 invincible and it the past week the alarm has gone off randomly multiple times while parked up. initially after 20 mins of sitting around. 

Ive checked the Battery status and it displays a healthy 12.3 volts. 

I have removed and cleaned up any signs of corrosion on the negative connections to the Battery and body. Also the positive terminal. since cleaning the alarm did not sound till the 8th hour , a much longer interval than prior to the clean. 

Other checks:

The hidden vehicle status display on the head unit is also reporting 12.3v.

The only way i can set the alarm now is with the interior sensor turned off using the button in the overhead light.

Ive checked the whole car for critters and carefully vacuumed the dust out of the sensor. 

Im now at a lose as to what is going on. 

My thoughts; have i masked the issue by cleaning the Battery connections. Possible early vehicle battery failure? is it that simple just change the battery?

Hood switch i have ruled out as i would expect the alarm would still trigger if this was the issue even with the internal sensor turned off?

Before i start substituting the interior sensor has anyone found the source of the issue?

Thanks for your advice. 

Si

[IanML]

As you have isolated the issue to the interior sensor, one possibility is a resident spider (or other insect).  A good vacuuming may help.

[Sioo7]

Well That's interesting.

Just checked the vehicle Battery again and even though its reading 12.3V with the car unlocked and ignition off, when ignition or power on is selected the voltage drops to 11.8V. First signs of a weakening Battery. The more accessories i switch on i.e the radio the further it drops in moments. 

Does anyone know what the volts drop threshold voltage is that would trigger an event that causes the alarm to sound off?

When i connected the Battery to a Snapon condition tester it failed the test indicating the battery had less than 50% power in it despite a 15 min drive. Alternator charging all checked out. 

Conclusion that the weak battery drained itself during the colder night and triggered the alarm. 

Turning the interior sensor off was just saving power and gave me a false diagnosis it would seem.

New Vehicle Battery about to be fitted so time will tell if that resolves the issue.

In any case the battery was starting to fail and with winter just about to hit us it was a good time to change it.

fingers crossed that this sorts everything out.

 

 

 

[Sioo7]

23 minutes ago, IanML said:

As you have isolated the issue to the interior sensor, one possibility is a resident spider (or other insect).  A good vacuuming may help.

Hi , I did carry out the Vacuuming trick a few days ago but it didn't fix it unfortunately. 

[Sioo7]

Happy to report that replacing the Vehicle Battery has resolved the random alarm activation. 

Don't be fooled by the interior movement sensor . In my experience by turning it off is just reducing the drain on the Battery. (im an electronics engineer of 40 years)

I believe the lack of use of this car during lockdown had impacted the charge cycle of the Battery causing it never to recover fully once driven. 

My advice if you are finding the alarm randomly going off after a while of being parked or especially at night when the temperature drops, is first clean the earth connection to the chassis from the battery and terminals. This will improve and increase the duration between alarm soundings but ultimately get the Vehicle battery tested. If its below 55% capacity then replace it.  

This battery was only 6 years old and the original supplied with the Rav from Toyota.

With the new battery fitted from the Motor Factors i have had no false alarms in the past 20 hours and the outside temperature dropped below freezing last night. 

I hope this article helps someone diagnose their alarm sounding issues. 

thanks

[satts67]

What were the fluid levels like in the old Battery? If Battery voltage has dropped below 12V (engine off) after lack of use always good to trickle charge or long run during the day with everything switched off to recover the Battery health.

 

[Sioo7]

well here we are a week later after changing the Battery and its now randomly going off again. 

Battery Voltage is 12.3 with everything off. and with everything off. 

ive had almost a week between false alarms. 

really at a lose as to what is triggering this now. 

the car is used every day and starts fine. Its a short journey to work around 3 miles.

is it not getting enough Battery charge recovery time?

I can stop the false alarms by pressing the button to turn off the internal sensor. 

A car driving past the car set it off earlier before i i turned off the internal sensor. 

there must be a way to turn down the sensitivity? 

Can some one help me.

Thanks 

[ernieb]

The Battery voltage off load seems on the low side to me. I thought a healthy Battery was between 12.4v and 12.8v and that 12.2v was about 50% charge, all rule of thumb. If it gets cold then the alarm might just trigger, assume you’ve checked the Battery voltage when the car is running to see it’s being charged OK?

[Sioo7]

30 minutes ago, ernieb said:

The battery voltage off load seems on the low side to me. I thought a healthy battery was between 12.4v and 12.8v and that 12.2v was about 50% charge, all rule of thumb. If it gets cold then the alarm might just trigger, assume you’ve checked the battery voltage when the car is running to see it’s being charged OK?

Hi. the charge voltage is 14.22 volts so that appears to be working correctly.

Its a bit of a mystery

  

[IanML]

It is said that it takes 20 minutes running to replace the charge used for one start.  If that's the case, maybe your car is just not getting enough charging on its 3 mile run.  Try putting a trickle charger on overnight say once a week.  If you haven't got one, I recommend CTEK MSX-5

[Sioo7]

19 minutes ago, IanML said:

It is said that it takes 20 minutes running to replace the charge used for one start.  If that's the case, maybe your car is just not getting enough charging on its 3 mile run.  Try putting a trickle charger on overnight say once a week.  If you haven't got one, I recommend CTEK MSX-5

I have just stuck the Battery on a 3amp low charge now to see if that improves the situation. 

Im still baffled at by turning the interior sensor off stops the alarm activating? 

ian thanks for the recommendation . i will check out Amazon. 

This is a brand new Battery after all . 

Has anyone else experienced this issue?

 

 

[philip42h]

I did have a similar 'sounding' issue a while back - with a Volvo rather than a Toyota - where the alarm went off when it felt like it, typically during the night. It eventually turned out to be a fault in the wiring loom and adding an extra wire between the interior sensor and wherever it connected back to solved the problem permanently ...

[Sioo7]

16 minutes ago, philip42h said:

I did have a similar 'sounding' issue a while back - with a Volvo rather than a Toyota - where the alarm went off when it felt like it, typically during the night. It eventually turned out to be a fault in the wiring loom and adding an extra wire between the interior sensor and wherever it connected back to solved the problem permanently ...

Ive been on the phone to Toyota main dealer and asked the question. Ans no way to adjust the sensitivity on the movement sensor.

Dam, 

So advice they suggested is to charge the Battery fully again and see if the duration between events increases. If it does then it points to Battery recovery issue due to limited use between starts not allowing the Battery to fully recover. Meantime i went with the recommendation and bought a CTEK MSX-5 and a ANCEL BST200 Car Battery Tester. This way i can get into weeds of the issue. 

Toyota also said that the interior sensor never seems to be the source of the issue and never gets replaced. Its a £280 item 😛

 

[Sioo7]

CTEK  plugged and and charging after:

I took the Rav for a longer run and then analysed the Battery condition. It reported 699 on a 740ah battery 

Clearly the alternator is charging. 

i locked the car and waited. 18 hours later and another cold night, not a peep from the alarm.

I have the CTEK plugged in now and hoping to recover the Battery condition to 100% 

time will tell if i have a duff new Battery or not 

[ernieb]

@Sioo7, sounds like you have an action plan which is always a relief, hope it just needed a longer charge. I’ve had experience of a new Battery being fitted that was not fully charged, I guess it had been hanging around for some time. Anyway after a really long dive it was all good.

[Sioo7]

2 minutes ago, ernieb said:

@Sioo7, sounds like you have an action plan which is always a relief, hope it just needed a longer charge. I’ve had experience of a new battery being fitted that was not fully charged, I guess it had been hanging around for some time. Anyway after a really long dive it was all good.

I am too young to go mad lol hopefully as you say get some life in the Battery and my neighbours can have some unbroken sleep and i can feel less stressed 🙂

 

[ernieb]

I can understand about the stress and whilst neighbours understand in the short time they need to know you’re on the case, good luck with it all.

[Catlover]

1 hour ago, Sioo7 said:

CTEK  plugged and and charging after:

I took the Rav for a longer run and then analysed the battery condition. It reported 699 on a 740ah battery 

Clearly the alternator is charging. 

i locked the car and waited. 18 hours later and another cold night, not a peep from the alarm.

I have the CTEK plugged in now and hoping to recover the battery condition to 100% 

time will tell if i have a duff new battery or not 

My experience of the CTEK 5 is it can take a Battery up to 80% quickly (as per the manual), then the next stage takes it up to 100% but that can take a few hours (as per the manual).           
A friend had a Battery lying in her dads (now deceased) garage. She didn’t know if it was good or not. I offered to do. CTEK on it. It went through all the stages without a hitch. I gave it back to her saying although it looks good it may not be. When she had her car MOT she got the garage to load test it and they pronounced it dead. So that was that, she is taking the Battery to the tip.

[Sioo7]

39 minutes ago, Catlover said:

My experience of the CTEK 5 is it can take a battery up to 80% quickly (as per the manual), then the next stage takes it up to 100% but that can take a few hours (as per the manual).           
A friend had a battery lying in her dads (now deceased) garage. She didn’t know if it was good or not. I offered to do. CTEK on it. It went through all the stages without a hitch. I gave it back to her saying although it looks good it may not be. When she had her car MOT she got the garage to load test it and they pronounced it dead. So that was that, she is taking the battery to the tip.

Hi , This is a new Battery and claims to be 740amp, the CTEK 5 Is showing a fully charged light at position 7 ( agree position 6 is 80%) but still can only achieve 700amps when analysed? 

Is this normal ?

[ernieb]

18 minutes ago, Sioo7 said:

Hi , This is a new battery and claims to be 740amp, the CTEK 5 Is showing a fully charged light at position 7 ( agree position 6 is 80%) but still can only achieve 700amps when analysed? 

Is this normal ?

I think you’d need to look at the spec how they rate the Battery, temperature, general load conditions, etc., it’s about 5% lower than the rating you’ve indicated then it does not sound too bad.

[Sioo7]

37 minutes ago, ernieb said:

I think you’d need to look at the spec how they rate the battery, temperature, general load conditions, etc., it’s about 5% lower than the rating you’ve indicated then it does not sound too bad.

That's good to know and its a cold day also. These toyota alarms really dont like an undercharged Battery do they. As soon as i get some decent power in the Battery then my false alarms stop. 

 thanks for your assistance 

[Sioo7]

Well that was all a waste of time . The alarm has gone off again. The only way i can stop it is turn the interior sensor off. 

Has anyone had one of these fail?

[Cyker]

Is it going off again with the CTEK charging it or is it with just the Battery on its own again?

Really baffling from what I've read so far!

 

[ernieb]

8 hours ago, Sioo7 said:

Well that was all a waste of time . The alarm has gone off again. The only way i can stop it is turn the interior sensor off. 

Has anyone had one of these fail?

Sorry to hear that, I'd think the sensor is pretty robust but you never know.  I think Philip suggested that you might want to check out the wiring to see if that was still making good contact.

[Sioo7]

9 hours ago, Cyker said:

Is it going off again with the CTEK charging it or is it with just the battery on its own again?

Really baffling from what I've read so far!

 

The CTEK was removed after indicating a full Battery, so it was on the vehicle Battery, Turn the internal sensor off using the button and all is quiet.