I am befuddled with the alarm system that came with the Volvo. When the alarm system is activated, I only get flashing blinkers/lights and an ignition that doesn't work...BUT where's the audible alarm siren? Does anyone have this problem, or are all Volvo stock alarms just show, with no "bite"?

My car doesn't seem to have an alarm at all, although the horn connector is there. Anyone tell me where was the alarm box fitted, how is it activated etc., or is it part of the ECU ? In other words, might I have an alarm and not know about it?

KP

850 Turbo 1994

Tha alarm ism prewired. Instalation consists of replacing a couple of relays in the drivers footwell, installing the LED in the dash, and a horn. It is armed/disarmed by the central locking system.

That's interesting and potentially useful! Where is the LED usually mounted? I ask because I have seen an 850 parked which had a flashing red LED to the right of the LCD display on the Radio/Stereo untit (looks like an SC800)...

KP

There should be a horn mounted to the firewall with a 2 wire conector. They are not extremely reliable. To test the wiring, open the hood and manually close the drivers side latch. Unplug the horn lead and attach a test light. Now lock the car(with hood open but latch closed) and arm the alarm. Trip the alarm and your test light should flash. If it does, the wiring is ok and the horn is dead. By the way, the horn only sounds for about 30 seconds when working properly. The flashing lights continue but for how long I don't know.

Oh yes it can get loud. Try this. Leave your windows down, close the doors and lock it with the remote. Now reach in real casually when your in public and just pull the lock knob up. Now while you are looking your most suave, open that door.

Good luck.

When I lock my door manually with the key or with the remote, the light on the dash starts to blink; if a door is opened without disarming the system the horn starts honking. Test it out sometime, preferably during daytime hours so your neighbors won't hate you.

That is the exact scenario that results in my Volvo flashing lights, bit no horn or audible alarm. Wonder if anyone has any ideas about how I may be able to enable the audible part of the alarm. Thanks.

my alarm horn also did not work, so i thought. I turned the screw comming out the front of the horn and adjusted the volume, now mine works.

after i heard it i realized the previous owner must had turned it off. the sound is not loud enogh to be heard in my house with the car in the driveway.

i am going to have to replace it with a better horn.

turn the srew may help.

Dan

I think there is a seperate horn/siren for the alarm. Mounted up on firewall in front of passenger side on mine. Maybe you have a loose wire to it or something??? Not really sure, just bought this 850 to replace the old 240 with 280,000 and haven't really got into it yet....

There should be a round alarm horn attached to the middle of the firewall in the engine compartment. The alarm does not use the car's horn. Check the connection or maybe tap it a bit to see if that helps.
Dave H.
93 854GLT
96 855

ALarm Horn???? is this the thing in the middle of the firewall at the top above the Turbo? round, black and thin? with a screw type bolt commomng out of it? my alarm also makes no audible sound and i have often wondered why?

i thought the thing looked like some sort of emissions thing looks like a vacume diaphragm.

So thats a Horn? DAMN I FEEL DUMB

Dan

That's the alarm. Kind of like a motorcycle horn. I went out yesterday after work and tried my system and it worked as described here. Not too loud though. Maybe I'll play with a louder horn.
--
Erwin in Memphis, '95 855t

i adjusted the big srew out the front of the alarm horn and it did in fact adjust the volume just like a motorcycle horn.

turn it out and it gets louder, turn it in and it gets quiet.

it sounds sick and i will replace it

Dan

if that is it, then it may be like a motorcycle horn in that you can adjust the loudness by turning the screw that comes out of the center.

Have you tried to adjust this in or out and see what happens?

I am going to check mine out tonight to see if i power to the horn or a bad horn. i might turn it bouth ways to see if it makes it louder, i have had motorcycles that if you turn the screw enough they made no sound at all!!

Dan

if that is it, then it may be like a motorcycle horn in that you can adjust the loudness by turning the screw that comes out of the center.

Have you tried to adjust this in or out and see what happens?

Dan