Horn won't quit honking

Can somebody help? My car horn starts honking and the lights start flashing, spontaneously. The neighbors are going to kill me if I don’t die of sleep deprivation first. The problem started a few minutes after 6 a.m. yesterday, and stopped when I turned the car on. I left the car running in the driveway (illegally) and then cut it off after about 30 minutes, and all was quiet until around 8:45 a.m., when it started again. The only way I can get it to stop is to press the UNLOCK button on the car’s remote; but that doesn’t make it quit for good, sometimes only makes it quit for a few seconds. Anyway, I drove the car to work and it was nice and quiet all day. (I went by the mechanic’s on the way to work and had to set an appt. for Monday but I don’t think I can stand it until then. This morning the honking/flashing began at 1:52 a.m. I pushed the remote. It stopped until 2:08. It kind of went like that until I finally started up the car. It is now emitting carbon and I am a zombie. What can I disable or override until a mechanic can take care of this? Is it a mechanical problem? A goofed-up sensor? Is this tied to a computer chip problem? I know that some Subarus had a recall on a computer chip, I got a letter and contacted the service dept. of local Subaru dealer for an apt. but have not gotten a call back. It has been pretty cold (for Nashville, TN) for the last 2 nights - would cold trip a faulty sensor? The car isn’t sitting in the wind, we’re geologically pretty stable here, I have no answers and would like a clue. Thanks.

I’ve been having the same problem with my 2000 Blazer since a close lightning hit last July. About once a month the alarm will go off during a rain storm and the power door locks are disabled, i.e. the key fob will not deactivate the alarm.

I have to disconnect the battery at the negative terminal (never disconnect a battery by the positive terminal) to shut off the alarm and reset the system to get the locks working again. At the suggestion of some of the forum members, I disable the alarm by locking the door manually. Read the Owner’s manual closely to see if there is a procedure to disable the alarm on your Subaru. The next time it rains I will pull the fuse for the horn in case the alarm goes off in the middle of the night.

Ed B.

Locate the alarm or horn fuse and pull it!

Why didn’t you just disconnect the battery?

Think big hammer.

Is this a FACTORY alarm system or an aftermarket alarm…makes a HUGE difference. I was a pro alarm installer for many years and if you have an aftermarket alarm there are several things I can walk you thru including putting it in valet mode disabling it/adjusting it etc… If its factory…you are on your own aside from looking at the owners manual and going into Valet mode if possible.


Checking the service manual to my daughter’s Forester, it seems that it is an integrated alarm and it seems to use the ECM - so it may not be as easy as snipping a wire or pulling a fuse.
It has the following sequence for turning the alarm on/off. It very likely is the same for your year:

    When steps 1) to 4) are performed with the security
    system setting ON, the security system setting is
    switched to OFF.
  1. Close all doors and the rear gate, then sit down
    on the driver seat. Press the UNLOCK button of the
    keyless transmitter.
  2. Turn the ignition switch to ON.
  3. While turning the center door lock switch to UNLOCK,
    open the driver’s door, and keep this condition
    for 10 seconds.
  4. Switch the security system setting (ON⇔OFF),
    then the horn sounds.
    OFF → ON Horn sounds once.
    ON → OFF Horn sounds twice.
    See the following for security system ON/OFF setting
    with the select monitor. <Ref. to SL-45, PROCEDURE,
    Security Control Unit.>

Of course, this would mean your alarm will be turned off so you don’t have its protection but at least it will get you a restful night’s sleep so you can get to the dealer the next day.
Hope that’s useful.

Yeah man…do it… that’s exactly what I wanted you to find in your owners manual. Hell of a thing, aint it?