The RAV4 Hybrid is one of the best-selling hybrids on the market.
As is the case with any vehicle, it can suffer from alarm-related problems.
If your RAV4 Hybrid’s alarm keeps going off, this article is here to help…
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Why Does My Toyota RAV4 Hybrid Alarm Keep Going Off?
A Toyota RAV4 Hybrid alarm is usually triggered by a faulty door switch or hood switch as these sensors are prone to defects or damage through years of use. Other common causes include battery issues, key fob defects, and interior motion sensors.
1. Faulty Door Switches
Faulty door switches (including the rear hatch) are a common cause of random alarms. If damaged, faulty, or dirty, they can send false readings thereby triggering the alarm.
Door switches are a common point of failure as they are subject to wear and tear due to the doors being continually opened/closed/slammed etc.
The door latches and door switches can get dirty too which can cause issues, so the first thing you should do is give all door latches a good clean and spray some WD-40 on the latch and work it in to see if that helps.
Also check the wiring leading from the body into the door for any signs of damage, it should be in a flexible hose on the hinge side of the door.
If you suspect the alarm issues are linked to the door switch, ask your dealer to run a diagnostic test to try and pinpoint the fault.
One owner mentioned this on RAV4DriversClub.com:
“Might be worth checking the door switches and hood too if that has a sensor switch.”
2. Faulty Hood Switch
A faulty hood switch is a common cause of unwanted alarms for the RAV4 Hybrid.
The switch is typically embedded in the hood latch.
The small electronic device is designed to detect whether the hood is open or shut and is an important part of the car’s alarm system – if it is broken, loose or dirty it can send false readings to the car’s computer thus triggering the alarm.
- Pop the hood and locate the hood switch.
- Check for any obvious damage, rust or loose connections.
- Give the hood switch a clean too (use contact cleaner), as dirt and grime can cause issues.
- You can test the switch with a continuity tester.
If you are well-versed mechanically, you can buy a new hood switch online and replace it yourself. Otherwise, we’d advise visiting your local mechanic.
Related: 9 Best & Worst Toyota RAV4 Hybrid Years (Pictures & Stats)
3. Loose or Bad 12V Battery Connections
Loose or bad 12V battery connections can cause a number of problems, including triggering the alarm of your vehicle.
A bad connection can be caused by dirt or gunk buildup.
The terminals may have come loose from driving and vibrations etc.
Make sure the engine is off before doing any work on the battery.
- Inspect the battery and look for any signs of damage, dirt build-up, rust, or corrosion.
- Disconnect the battery and loosen the nuts on the clamps using a wrench.
- Remove the negative clamp, marked with a – symbol first.
- Clean the terminals with a toothbrush dipped in a mix of baking soda and water, rinse with distilled water and dry with a cloth.
- Reconnect the battery, ensuring tight connections.
One owner suggested this on ToyotaOwnersClub.com:
“You could try disconnecting the car battery for a minute and seeing if this resets anything…”
4. Drained 12V Battery
A faulty or weakened car battery causes a variety of problems, including accidentally triggering the alarm.
The best thing to do is take your unit for a battery health check, these are usually quite inexpensive or sometimes free such as at AutoZone.
Or you can test it yourself with a multimeter (see the guide at the end of this article).
A healthy 12V battery should be about 12.6 to 12.8 volts while a weakened battery reads below 12 volts.
“If the battery voltage is low, the obvious thing to do is charge the battery, ideally using a battery charger…” – RAV4DriversClub.com
“First make sure your vehicle’s battery is ok. It should have 12.5 volts. If you don’t have a voltmeter then try to jump start it. A low battery will cause all kinds of problems…” – JustAnswer.com
5. Key Fob Running on Low Battery
A common cause of mysterious alarms is a low key fob battery. Similarly, if the fob is dirty or dusty this can also cause alarm issues.
Give the inside of your fob a clean and replace the battery to eliminate this possible cause. It’s worth spending a bit extra for a good brand of battery.
- To open your key fob, stick your prying tool into the slit or gap between the two halves of the outer casing and gently apply upward pressure to pop open the device.
- Remove the battery.
- Give the key fob a good clean to remove any dirt or fluff – a cotton swab and some rubbing alcohol should do the trick.
- Check for damage, rust or loose connection (you may need a new key fob depending on what you find).
- Be sure to insert the new battery facing the right way up.
- Assemble the outer casing of your key fob by clamping them back together.
One owner shared this on ToyotaOwnersClub.com:
“Went online and checked and a lot of people said to change fob battery which l did. It stopped for a while…”
6. Faulty Key Fob
Another reported cause of nuisance alarms on this vehicle is a faulty key fob.
If you have 2 remotes, try taking the battery out of one and use the other for a while.
If the alarm problems persist, and you have tried cleaning the inside of the fob(s) and changing the battery, the best thing to do is speak with your dealer.
7. Interior Motion Sensor
Some RAV4 Hybrid models are equipped with interior motion sensors that can be triggered by bugs, moths and flies trapped in the cabin.
Give the vehicle a thorough vacuuming and spray some bug spray, you can also disable the interior motion sensor for a few days to see if the problems goes away.
To disable the interior ultrasonic sensors:
- Press the button on the roof panel
- Switch off the car
- Lock the car
“Sometimes the interior sensor is triggered by an insect. A thorough vacuum cleaning may help.” – ToyotaOwnersClub.com
“The most likely culprit is the intrusion sensor (and the intruding creepy crawly). As Pete said above, you can disable that part of the alarm system each time you set it … There is also a dealer customization setting to reduce the sensitivity of the sensor from Standard to Low which might help.” – ToyotaOwnersClub.com
“I had this with my Corolla last year and as much as I thought people’s suggestions were mad about it being an insect I just bit the bullet and cleaned out the car with a duster and then fly sprayed the interior and shut all the doors and locked up, came back the following morning to find a fairly large whispy looking insect (not a moth) and since then I’ve had no problems.” – ToyotaOwnersClub.com
8. Incorrectly Installed Aftermarket Alarm
An incorrectly installed or faulty aftermarket alarm system is a common cause of nuisance alarms.
Aftermarket alarms are typically far more complex than any factory-installed equipment which makes them more prone to issues.
They may also have been installed by incompetent individuals.
If you are experiencing issues with an aftermarket alarm, the best thing to do is speak with a reputable auto electrician.
9. Faulty Body Control Module (BCM)
A faulty body control module can cause a wide range of issues including nuisance alarms.
- The BCM is in charge of electrical communication from different electronic systems.
- This includes the alarm system, lock-unlock functions, climate control etc.
- If you have a faulty BCM you may notice other electrical glitches too
- This can include intermittent operation of various electrical functions, such as the horn, lights, wipers and instrument cluster dials
The signals sent from the door and hood are sent to the BCM to be interpreted and it is a core part of the alarm system.
The BCM can be connected to a diagnostic scan tool which should uncover any errors or show a lack of communication with the main computer.
If in doubt, speak to your local dealer or a reputable mechanic to carry out the tests for you.
10. Damaged Wiring
Damaged electrical wiring can cause a wide range of problems, it can often be tricky to pinpoint too and you may need to have an auto electrician run some diagnostic tests.
In some instances, rodents may have chewed through an electrical wire.
11. Animals Climbing On The Vehicle
If your alarm has been set off in the middle of the night, it may have been by an animal climbing on the car.
States such as Illinois, Indiana, Iowa, Texas, Wisconsin, and Carolina have large wild raccoon populations.
Have a look for footprints on the hood and the roof.
If you have a CCTV system, examine the footage. These animals usually appear during the night.
12. Not Closing Doors, Hood, or Trunk Properly
Something as simple as not properly closing the doors, hood, or trunk will inevitably trigger the alarm.
Make sure to check if you have closed every point of entry of your vehicle to avoid accidentally tripping your vehicle’s alarm.
Alternative Suggestions
Check for Recalls or TSBs
By entering your car’s VIN number on Toyota’s recall page or the NTHSA’s Safety Issues & Recalls page you can determine whether or not there is a TSB or recall for your vehicle and if there is you’ll want to get it addressed.
A recall is issued by a vehicle manufacturer for issues that are safety-related, while a TSB covers components that may be malfunctioning but don’t compromise the safety of the vehicle.
Disconnect the Battery
Sometimes mysterious alarm problems can disappear with a simple reboot, there are no guarantees here but it’s worth a try.
Disconnect the battery for 20 seconds and this resets many of the electronics in the vehicle.
Check For Warning Messages
When the alarm occurs can you see any lights or warning messages on the instrument panel?
This can give a clue as to what’s causing the alarm e.g. ‘Hood Ajar’.
Take it to a Toyota Dealership
If needed, take your Toyota to the dealership.
Tell them you are NOT paying for a check on what the problem might be.
Ask them if they will check it for free.
Most dealerships and other places do quick/initial diagnosis for no money as they plan to make money for the repair of your vehicle.
If your unit is still under warranty then they should fix and resolve the issue for free.
How to Test the 12V Battery
How to Test the Battery:
- Before testing, remove the surface charge from the battery, this allows for an accurate reading.
- Simply turn on the headlights for 2 minutes then turn off.
- Set the multimeter dial to the ’20 Volts’ setting.
- Make sure the car is turned OFF.
The multimeter will have a red probe and a black probe.
- The red probe is for making contact with the positive terminal.
- The black probe is for making contact with the negative terminal.
Measure across the battery terminals.
- The meter should display a reading, if the battery is fully charged the voltage should be between 12.2 and 12.6 volts.
- Anything under 12V and the battery should be charged or replaced.