adding extra siren

I want to add an extra siren to my Toyota celica 190 (2001 uk model) standard alarm system which is a TVSS IV-D.

In the USA I think its called a celica GTS but I dont know if this alarm system is fitted in the USA models.

I have been told that this alarm is digital so I cannot add an extra siren.Is this true?.

I have looked at the exsisting battery backup siren and it has 5 wires going to it.--------One is a perm 12v, another is a perm earth and I dont know what the other 3 are but none of them have 12v at them when the siren is sounding.

I hope someone can help.

Thanks

Mart

Most standard or "factory installed" alarms in the USA do not use a siren...the system will honk the horn.

If your vehicle has a siren it may be a dealer installed system. Regardless you need to determine what is going on at this siren. Test the wires at the siren and see what is going on Use a digital multimeter set on voltage to prevent any possible damage to the systems output..typically it will have 2 wires..one to ground (or "earth" as you say) and one should show 12volt+ when the siren sounds. Some older systems did it the opposite so you should check..if you visibly see one of the siren wires to earth..you know the other has to be positive 12v for the siren to sound.

Now I don't know who told you it is a "digital" alarm and you can't add a siren.I don't even know what "digital alarm" means....But either it is a siren..or a speaker. If it is a speaker it will be more involved to add a siren..but should be possible..but if it is a siren under the hood post back the color and polarity of the wires and I will post a simple relay/diode circuit to let you add as many sirens as you like.

Take care.

Thanks for the quick reply

Ihave looked inside the siren unit and it is a speaker and a circuit board with various chips and components on it but no relay.

Also from what I can gather by reading the UK forums some of the META systems are digital and they have a 12v and ground but it is triggered by a digital signal wire so you can only use the correct siren for that particular alarm.

If it has a circuit board inside it is a siren....a speaker would have nothing but the speaker in it..that circuit board is what creates and amplifies the occilating noise you hear from the speaker part of the siren.

Regardless...if there are 2 wires coming out of the siren...use a digital multi meter and take a reading.  It's that simple..trust me.

There will no relay inside the siren but if you wish to add additional siren(s) you will be using one. But I need to know the polarity of the wire that the brain puts out when the siren is sounding..most likely a positive but I need to be sure.

Talk to ya later.

Referring back to my original post, I need to investigate what the other 3 wires do.

A job for the weekend methinks.

I'll let you know how it goes.

ok so there is a battery backup siren, is that the only siren? If it is there still needs to be a wire from the alarm module to tell it to sound. I can't imagine that would be digital, just no reason for it.

I have checked all the wires to the siren and no matter what state the alarm is in (off,armed, or sounding) nothing changes on any of the wires so I do think it is a digital system.

What I have done in the end is to open up the siren and solder a wire directly to one of the speaker wires which gets 5.7 volts to it when it is sounding and used a 5 volt  2A relay to power 2 extra sirens ( one inside and one outside the car)

The siren outside the car is a DEI 514T and I do have a question regarding the black wire loop.Do I have to cut the wire only if I want full volume arm/disarm chirps or does this apply to when the siren is continuously sounding as well?

it is only for chirps, the siren will sound normal when it is going off.

Good idea using the 5v relay, that's what I would have suggested you try as well if it got to that point. I am still curious as to how that system works..i was not able to find any useful technical information online about the unit or it's wiring schematic.

Let us know if the extra sirens are working alright and if you need any more help.

Take care.

All I could find out myself was that it is a dealer fitted system and when I managed to find the main control unit it was a TVSS IV-S made for TOYOTA by FUJITSU TEN.

I e mailed fujitsu ten and asked for info but they never replied.