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Toyota Sienna Alarm Goes Off Randomly

My 2010 Toyota Sienna alarm keeps going off randomly…there is no method to the madness. It happens after it’s been running or not. It happens at all hours of the day and night. It can happen four times in a row and then not for days on end. It’s literally driving me insane. I can stop it by pressing the unlock button on the remote. But it will often – though not always – do it a few more times after that. So, I open all the doors/trunk remotely and that usually puts an end to it for that period…but not always. But it always happens again…whether it’s the next day or seven days later. The mechanic says they need to keep the car and hear/see it happen…but that means leaving my car with them for days on end, which I simply can’t afford to do. And they won’t pay for a rental (though I would think this would be covered by a warranty…they say no). Someone, anyone…help!!! Any ideas? Thanks.

I know it’s frustrating! hmm … well, no harm done if you – yourself – take a quick look-see. Visually inspect the wiring and switches on all the doors and the trunk. These are usually near the hinge areas. You might spot a wire that has frayed and the insulation is worn off. Or a switch or connector that has come loose.

It seems like your local shop should have at least offered to do this for you, maybe they already did and didn’t see anything, but if they didn’t, you can do it yourself without much difficulty.

I expect the problem is more complicated than this. The sensors involved in the alarm systems can be quite tempermental. What if you asked the shop to simply turn the alarm system off? Lots of cars have no alarm system at all, and the drivers seem to get by. Would that work for you? If not, to solve the problem, you’re probably going to have to do what they say: You rent a car for a week, while they keep your own car at the shop.

Too expensive? Have you phoned around for one week rental rates? I’ve gotten one week unlimited miles rental cars for as little as $150-200/week. If fact when I drive long distances, like if I’m driving from California to Denver which I do once in a while, I routinely rent a car for this. i think it’s cheaper than driving my own car. Sometimes I have to reserve a few days or weeks in advance to get the lowest rate. And if I call one day and don’t find a good rate, I’ll call back a few days later, and magically the rates have decreased in half. It depends where they have extra cars, which varies daily. I find I get the best rate usually at an Avis based in a near by local Sears Auto. Try a place like that. The local “Enterprise Rental” place offers good weekly rates too, but at least here they rent only if you drive the car in the same state as you rent it. That usually doesn’t work for me, but it might for you. The rental places at the airport usually are more expensive.

I bought a new Sienna in 2001 a few weeks after the Trade Center towers went down. It has an alarm, and it also would and does fire off almost at random. First, the dealer folks said it was a Toyota alarm, but later a smarter man actually read the computer history, and that was a TRW alarm installed at the port of entry to comply with Texas laws requiring an alarm on new cars.

Mine does it more when the weather is hot, but not necessarily. so, I would say first find out by VIN if it is a Toyota alarm or a brand-X alarm, as mine was.

though the alarm was installed by Toyota folks before it reached the dealer, they told me tough luck, it is considered my personal modification of the vehicle. They did offer to install a new Toyota alarm for $400 or so. I was and am displeased with Toyota for this nonsense. They install it, and make me pay for it, then claim they are not responsible.