# Alarm goes off sporadically, even when not set **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** toyota, highlander\ **Created:** [September 17, 2017, 6:16pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861 "2017-09-17T18:16:45Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![Dennis\_in\_Texas](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dennis\_in\_Texas](https://community.cartalk.com/u/Dennis_in_Texas)\ **Post date:** [September 17, 2017, 6:16pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/1 "2017-09-17T18:16:45Z")
Highlander Limited, 2010, alarm goes off sporadically after driving. Lately, it has even gone off WITHOUT being set! Anyone have any suggestions? The dealer can’t find any codes nor causes! ---
**Author:** ![lion9car](https://avatars.discourse-cdn.com/v4/letter/l/59ef9b/32.png) [@lion9car](https://community.cartalk.com/u/lion9car)\ **Post date:** [September 17, 2017, 6:41pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/2 "2017-09-17T18:41:08Z")
Is this a factory alarm or an aftermarket alarm? Does anyone near the car have the keys in a pocket at the time? Maybe the panic button is getting pressed accidentally. ---
**Author:** ![Cougar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cougar/32/21348_2.png) [@Cougar](https://community.cartalk.com/u/Cougar)\ **Post date:** [September 17, 2017, 7:14pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/3 "2017-09-17T19:14:02Z")
Exchanging the alarm system may be the easiest way to see if the trouble is internal with the system, which it sounds like may be the case here. ---
**Author:** ![Dennis\_in\_Texas](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dennis\_in\_Texas](https://community.cartalk.com/u/Dennis_in_Texas)\ **Post date:** [September 17, 2017, 8:42pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/4 "2017-09-17T20:42:19Z")
Factory, and no longer made. Specifically laid remote on counter to be sure wasn’t being caused by panic button accidentally being pressed. Dealership has no idea. ---
**Author:** ![Cougar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cougar/32/21348_2.png) [@Cougar](https://community.cartalk.com/u/Cougar)\ **Post date:** [September 17, 2017, 10:13pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/5 "2017-09-17T22:13:29Z")
You should be able to find OEM replacements through salvage yards or places that sell refurbished electronic auto parts at prices that are a lot lower than what dealer new prices would have been. ---
**Author:** ![VOLVO-V70](https://avatars.discourse-cdn.com/v4/letter/v/8e8cbc/32.png) [@VOLVO-V70](https://community.cartalk.com/u/VOLVO-V70)\ **Post date:** [September 18, 2017, 12:35am UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/6 "2017-09-18T00:35:05Z")
Just have the alarm disabled, most of the time they are ignored anyway. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [September 18, 2017, 12:42am UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/7 "2017-09-18T00:42:27Z")
Are any of the door open/closed switches acting up? Does the dome light come on when it isn’t supposed to, or the door open icon on the dashboard appear intermittently for no apparent reason? If so, that’s probably a good guess where to start looking, a defective door switch. It may just need its contacts cleaned. ---
**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\ **Post date:** [September 18, 2017, 1:04am UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/8 "2017-09-18T01:04:28Z")
There is a service bulletin that applies to some 2010 Highlanders, the security alarm may falsely activate due to a faulty hood switch. > [@dennis.moore14](#): > > Lately, it has even gone off WITHOUT being set! If the doors are not locked when the alarm sounds then the bulletin does not apply, this would suggest the panic alarm is sounding. Look in the vehicle for a lost key/transmitter. ---
**Author:** ![Dennis\_in\_Texas](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dennis\_in\_Texas](https://community.cartalk.com/u/Dennis_in_Texas)\ **Post date:** [September 19, 2017, 3:05pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/9 "2017-09-19T15:05:12Z")
No switch/door/dome light problems. The dealership checked all the switches and found no problems. Dennis ---
**Author:** ![VOLVO-V70](https://avatars.discourse-cdn.com/v4/letter/v/8e8cbc/32.png) [@VOLVO-V70](https://community.cartalk.com/u/VOLVO-V70)\ **Post date:** [September 19, 2017, 3:08pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/10 "2017-09-19T15:08:06Z")
@dennis.moore14 Do you realize that your name and email show up on the post when you reply by email? ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [September 20, 2017, 12:07am UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/11 "2017-09-20T00:07:09Z")
what does the owner’s manual say are the things that are designed to cause the alarm to go off? There should be a list, such as: Opening a door, opening the trunk or tailgate, opening the hood, someone touching the a metal part of the car, someone coming into proximity with the car, disconnecting power to the alarm, etc … If you want to figure this out yourself you’ll have to come up with that list, then eliminate the potential causes one by one. ---
**Author:** ![edTalk](https://avatars.discourse-cdn.com/v4/letter/e/ed8c4c/32.png) [@edTalk](https://community.cartalk.com/u/edTalk)\ **Post date:** [April 19, 2018, 6:54pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/12 "2018-04-19T18:54:33Z")
hi I have the same problem with my 2008. It is the factory installed basic alarm. if I do not lock the doors they lock automatically. I took it to the dealer who basically blew me off… it did go off when there, in a three football field dealership lot… Any, did you find a solution? it may be a faulty sensor on one of the locks, but i’d rather they just disconnect the alarm from the horn and lights; if I can find someone to do it rather than for the repair shop to go on a wild goose hunt replacing sensors one at a time. thanks… ---
**Author:** ![Dennis\_in\_Texas](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dennis\_in\_Texas](https://community.cartalk.com/u/Dennis_in_Texas)\ **Post date:** [April 21, 2018, 6:43pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/13 "2018-04-21T18:43:37Z")
Howdy- After I get out, I no longer have the issue. Now it happens after it sits in the garage, usually overnight, no alarm set, and the alarm will go off if I don’t start it after getting in. I have found that if you “unlock” with the key fob, if you don’t get in (open a door), it will automatically lock. Got same blowoff from dealership-factory-installed alarm no longer made, etc, etc. ---
**Author:** ![VOLVO-V70](https://avatars.discourse-cdn.com/v4/letter/v/8e8cbc/32.png) [@VOLVO-V70](https://community.cartalk.com/u/VOLVO-V70)\ **Post date:** [April 21, 2018, 7:48pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/14 "2018-04-21T19:48:37Z")
Repeating previous post. You should edit out your email address just because it is a good thing to do. ---
**Author:** ![Dennis\_in\_Texas](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dennis\_in\_Texas](https://community.cartalk.com/u/Dennis_in_Texas)\ **Post date:** [April 21, 2018, 9:22pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/15 "2018-04-21T21:22:33Z")
How do I do that. ---
**Author:** ![VOLVO-V70](https://avatars.discourse-cdn.com/v4/letter/v/8e8cbc/32.png) [@VOLVO-V70](https://community.cartalk.com/u/VOLVO-V70)\ **Post date:** [April 21, 2018, 9:35pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/16 "2018-04-21T21:35:06Z")
Click on the slanted pencil looking icon at the bottom of your post and you can edit . ---
**Author:** ![Dennis\_in\_Texas](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dennis\_in\_Texas](https://community.cartalk.com/u/Dennis_in_Texas)\ **Post date:** [April 21, 2018, 10:21pm UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/17 "2018-04-21T22:21:20Z")
There isn’t one on that one. ---
**Author:** ![VOLVO-V70](https://avatars.discourse-cdn.com/v4/letter/v/8e8cbc/32.png) [@VOLVO-V70](https://community.cartalk.com/u/VOLVO-V70)\ **Post date:** [April 22, 2018, 12:21am UTC](https://community.cartalk.com/t/alarm-goes-off-sporadically-even-when-not-set/107861/18 "2018-04-22T00:21:37Z")
@cdaquila Carolyn, could you remove the email address on post #9 for Dennis please.