My alarm keeps going off and car won’t start after changing battery, what can be wrong?
After changing the battery on my 2008 RAV4 the alarm continually keeps going off and the car won't start. I tried locking and locking the door with the key but it's not working I also tried disconnecting the positive terminal and leaving the driver door opened and it worked the first time but after the alarm went off again, I tried that and it didn't work. Now every time I tried to turn on the car the alarm goes off and then I hear this clicking noise for a while and then it stopped.
My car has 174000 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hello, and thank you for writing in. When dealing with alarm and starting issues, you are really dealing with a miscommunication with the alarm system. If you have a spare key, try using it to disarm the system and start it. You may also want to try key cycling ("Off"-"On" without starting), as it will make the computer reset its communication with all of the modules. It usually takes 3-5 cycles to achieve any kind of reset. Often with newer models, giving the vehicle some time to sit and trying again later helps the computer work through its programming, and it can reset itself. The longer the vehicle sits, more of the systems will shut off, and more of these systems have to restart when you try again (as some systems do NOT turn off when you turn off the engine, and they continue to use electricity to hold memory). One of the other ideas to consider is that the new battery is not fully charged, or your battery terminals are not allowing for a proper connection (either because they are loose or dirty, or have a bad ground connection). If none of the above gives you control over the vehicle, then you need to seek professional help. Contact our service department for a quote or to schedule an appointment.
How to Identify and Fix Common car Problems ?
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To reset your Toyota RAV4 anti-theft system, insert the key in the ignition to turn on the electrical system, but don`t start the engine. Leave the key in this position for 10 to 15 minutes, so the security light switches off, and then turn the ignition off for another three minutes.
If the battery in the electronic key is low then you may need to replace it. If the problem persists then the programming may have locked the vehicle out so it may need to have the system reprogrammed but that is not too common. Most of the time this is as simple as a key fob with a low battery.
One of the most common causes is an entry key fob with a low or dead battery. Key fob batteries can go flat after long periods of use. If that happens, the fob might not be able to send signals correctly, which can cause the alarm to sound.
You typically will not need to do anything to reset your car alarm after a battery change, but it should automatically reset for you. Some vehicles or alarm systems may require you to push a reset button on the alarm box that may be located near the steering wheel.
Most modern cars have a dash light that indicates that the anti-theft system has been triggered. The icon for the anti-theft system looks like a car and a lock combination. When this light is on and flashing (it will be either or blue), it will indicate that your car`s anti-theft system is activated.
To reset your anti-theft light, you can either use your key on your car door or in the ignition. To use the car door method, put your key into the lock on the door and turn it. Then, hold the key in the turned position for about 30 seconds.
Low car battery
One of the main functions of a car alarm is to warn the driver about low battery levels. That`s why turning the engine on with a dying battery will instantly set your car alarm off. How can I fix it?
If your ECU controls the anti-theft system, disconnecting the battery may lock you out of your car. Like desktop computers and most other electronics, disconnecting the battery cable for a short period will not fully reset your ECU due to the residual power remaining in the circuits.
Replace the battery and see if that resolves it. If the alarm to continues to be triggered, then you may have a wider electrical fault with the vehicle. Electrical issues such as a weak battery, a faulty alternator, or loose connections can cause the alarm to malfunction.
However, there are a few things you may do if you`re wondering how to stop the anti-theft mechanism without a key. One common method is to press and hold the “unlock” button on the car door for around 10 seconds; this should turn off the security system.
There are simple instructions if you want to know how to disable a car alarm permanently. You should just unlock the door, start the car, remove the fuse, or disconnect the battery of the car. When working with electronics, it`s crucial that you guard yourself against injury.
The brain and alarm features may be wired to the car`s main battery, but they usually have a backup power source as well. This hidden battery kicks in when somebody cuts off the main power source (by clipping the battery cables, for example).
Car alarms rely on the electronic component of the vehicle, and disconnecting the battery should both silence the siren and reset your alarm. Open up the hood, locate the battery, and with a wrench, remove the negative terminal. Then reconnect it after a minute has passed.
Use Your Key and Both Lock And Unlock The Driver`s Side Door
Locking and unlocking the driver`s side door can reset the switch and cause the alarm to cease. If the driver`s side door doesn`t work, try the passenger door. Further, try turning your vehicle on as well.
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My alarm keeps going off and car won’t start after changing battery, what can be wrong?
ANSWER : Hello, and thank you for writing in. When dealing with alarm and starting issues, you are really dealing with a miscommunication with the alarm system. If you have a spare key, try using it to disarm the system and start it. You may also want to try key cycling ("Off"-"On" without starting), as it will make the computer reset its communication with all of the modules. It usually takes 3-5 cycles to achieve any kind of reset. Often with newer models, giving the vehicle some time to sit and trying again later helps the computer work through its programming, and it can reset itself. The longer the vehicle sits, more of the systems will shut off, and more of these systems have to restart when you try again (as some systems do NOT turn off when you turn off the engine, and they continue to use electricity to hold memory). One of the other ideas to consider is that the new battery is not fully charged, or your battery terminals are not allowing for a proper connection (either because they are loose or dirty, or have a bad ground connection). If none of the above gives you control over the vehicle, then you need to seek professional help. Contact our service department for a quote or to schedule an appointment.
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ANSWER : Hi. There is a couple of things that could be wrong here. The battery or alternator that was just installed could be defective. Theses parts need to be tested for proper operation. There also could be a fuse, fusible link, or wiring for the battery or charging system that is blown or broken causing the battery light to come on.
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Car Won’t Start
ANSWER : Hello. From what you describe it would appear that your vehicle is having some sort of malfunction with the security system. It may be possible that the security system is enabled and preventing the vehicle from starting. This may or may not be related to the the recent battery replacement for the remote, or it could also be related to the EPS light. The EPS light comes on when the computer detects an issue with the vehicle’s electronic power steering system. There are cases where a steering malfunction will prevent the vehicle from starting, if the issue detected is serious enough to significantly affect the vehicle’s handling. It is unlikely that the brake fluid or engine oil are related to the issue, but it would not be a bad idea to make sure that they are topped off. I would recommend retrieving the trouble codes that are setting off the EPS light, as they will likely reveal some information on what the issue may be. Also keep in mind that a no start condition can be caused by other things, such as issues with the ignition system, or even the starter itself. As these sorts of electrical issues can sometimes be difficult to diagnose, I would recommend having a professional technician, such as one from YourMechanic, come to your location to [diagnose the cause of your warning light, and if it may be related to the no start condition.
