Horn wont honk when doors locked using remote. tried manually holding in door switches with no success

Sounds like one of the door ajar switches is not working. There is one on each door latch and you have to remove the door panel to get to them. The easiest way to diagnos it is to hook it up to a scanner and monitor the door ajar pids and see which one is not working.

Climb into the vehicle and close the door. Insert the key into the ignition but do not turn on the vehicle.
Hold down the "Unlock" button on the driver's door while turning the key to the right to the "Accessories" position. Continue holding down the "Unlock" button.
Turn the ignition key back to the "Off" position while continuing to hold the "Unlock" button then return the key to the "On" position again. Then return the ignition key to the "Off" position. As you complete this sequence, the doors will lock, and the horn will sound, indicating that you've entered the programming mode. At this point, release the "Unlock" button on the driver's door.
Push both the "Lock" and "Unlock" buttons on the key-less remote and hold them for roughly 15 seconds. Release the buttons when the locks click again.
Insert the key into the ignition and turn it to the "On" position. The horn will honk once more. This indicates the programming has been successful.
Remove the key from the ignition. Climb out of the vehicle and try locking and unlocking the doors with your remote key.
Tip

• The H3 uses a Tech ll code system that often cannot be re-programmed without the help of your local dealer. If you are unable to reset your key-less fob using the steps above, your local GM dealer will be able to help.

I have a 09 kia spectra, The only time the horn will honk. is when I lock the doors with the remote. Unlocking just makes the lights flash! God-Bless! and hope this helps you out.

If your vehicle is equipped with a factory keyless entry system and you have the owner's manual, there should be a section in the manual describing how to change your options with your system. But if you have an aftermarket system, which I am thinking this the case, you will have to manually go into your dash under your steering wheel and cut the wire going to your horn from the security system. Once you have accessed your wiring underneath your steering wheel, there is a main harness with a bunch of wires going to the steering wheel. In this harness you will find a DARK GREEN/VIOLET small gauge wire and you should see another wire tapping into it probably coming from the security module. Just cut it off but leave the DARK GREEN/VIOLET untouched and this will eliminate the horn honks.

I have a 2004 Dodge Durango. When I push the lock button it will lock door and set the alarm but the horn does not blow this is normal on my car. As Dodge is apart of Chrysler maybe it's the same for you, Unless in the past it did trigger the horn then the only thing I can think of is maybe there are different setting for your car. Check the owners manual. Hope this helps.

holdboth the lock and unlosk buttons on your remote simultaneously for about five seconds until the lights flash and horn chirps.that should do it.if not i believe these models used a separate horn for security system.possibly fuse for this horn is bad or the horn itself is bad.to see if this horn works lower drivers window.stand outside vehicle and lock doors with remote.wait about a minute and reach in window and MANUALLY unlock and open door(do not use power door lock button)this should cause the system to activate...horn should beep and headlamps should flash.if horn beeps try my first suggestion.if it doesnt beep and just the head lamps flash check fuses and horn for security system.

try changing the batteries in the remote.....

IMPREZA: 2005, 2006, 2007 and
FORESTER: 2005, 2006, 2007, 2008
Check for Immobilizer key on Forester XT models only.
information is always subject to change and correction
new remote for 2005 Imprezas.
This is not the same remote as the 05 Legacy/Outback remote which also has truck/gate release on the front and a red panic button on the back.
Lock: press Lock button for 2 seconds or so to lock car, and arm optional security system. The car with chirp once and turn signals flash for locked, 5 short chirps and signal flashes if any door is not fully closed. The dome light goes on for 15 seconds and ignition key ring (if present) will light for 30 seconds when unlocked.
Unlock: press unlock one time for driver's door, press again within 5 seconds to unlock all doors inkling rear gate (wagon). The system does not open the trunk.
Panic mode: press and hold lock button for approx. 3-4 seconds to activate Panic mode. I panic model the horn honks and turn signals flash until either the lock or unlock button is pushed again.
Finder mode: Press lock button 3 times within 5 seconds to activate Vehicle Finder mode. The horn will honk once and the turn signals will flash 3 times
Distance: works within approx. 30 feet depending on battery strength, nearby concrete walls and etc.
Audible Chirp On-Off: the system will chirp when locked or unlocked. To turn OFF the chirps, unlock the door and then push both lock and unlock buttons at the exact same time for 2+ seconds. There will be 2 chirps indicating the the audible is off. To turn the chirp back on, repeat the process and the system will chirp one time when it is back on.
Battery: as the battery ages it will only work as you get closer to the car. When a battery is replaced, the transmitter must be re-synchronized with the Keyless control unit. To synchronize, press the lock or unlock button 6 times.
Programming: 4 codes may be programmed.
Sit in driver's seat and unlock all doors. Open and close the driver's door
Turn the ignition key from LOCK to ON position 10 times within 15 seconds. Be sure to stop at both lock and on. The horn will HONK once to indicate transmitter programming mode is activated. Leave key in LOCK position and don't remove it from ignition.
You now have 45 seconds to complete the programming as below.
Open and close driver's door again.
Push either lock or unlock button on the remote you want to program. The horn will honk 2 times when successful.
To continue and program other remotes at the same time: open and close the driver's door and push lock or unlock on the remote. The driver's door must be opened and closed between each remote you want to program.
Done programming? remove the key from the ignition and the horn will honk 3 times.
DELETE old codes? Reprogram 4 times, it will overwrite old codes.
Alarm Security System: optional on all models. When locked there is one chirp (can be turned off, see above), the turn signals will flash and the red 'security' light will start to flash once every 2 seconds except for STi which flashes twice every 2 seconds.
There will be 5 chirps if a door, hood, and trunk or gate is not fully closed
You can also arm the system by using the power lock button on the driver or passenger door as you get out of the car and then closing the door behind you.
Disarm the system: push unlock for 2 seconds
Lost remote, alarm activated? When you can't use a remote to turn off the system: open the door with a key or try to start the car and the horn will start to honk. Turn the key on-off 3 times within 5 seconds and the alarm will go off and you can start the car. It's simple!
VALET mode: To set valet mode or just to disable the security alarm system: 1. unlock all doors 2. physically open the driver's door 3. hold the UNLOCK button on remote for 2+ seconds. The red 'security' light will then flash 2 times a second until the car is turned on.
System has been Tripped (except for STi): if you unlock the door with the remote and it chirps the signal light flash 4 times, the system has been triggered;
Identification mode: To find out what happened and why the system was triggered:
Open and drivers door, leave it open. Turn ignition key from LOCK to ON 2 times and then leave in LOCK position.
Tripped code: 1 security light flash: a door has been opened, 3 flashes when the impact sensor was triggered, 4 flashes when the ignition was messed with or battery disconnected

Your lock settings were most probably changed from your remote unit. By pressing both lock and unlock keys together for around two to three seconds you can switch between silent mode and horn mode. Hooe that helps...

If you have your owner's manual, there is a section that will tell you the exact sequence to press to enable/disable the horn bonk. It has three settings, chirp, honk, and off. The chirp is a really quick chirp of the horn. Honk is a longer honk. Off seems to be what you've set.

I hope this helps.