Car alarm failure.

[Shackeng]

Neither horn on the Elite car alarm is working. ( see my thread on Battery disconnection) Before I start delving into the car, has anyone got any ideas what it might be? Seems strange that neither works.

[Jimbob]

prev owner disconnected both cos of dodgy bonnet senor or sommat?

[Shackeng]

Possible, I'll email him to check.

[Shackeng]

Just spoke with Dave, it was working when he bought the car, annd he has not had any problem with it. I'll check the bonnet sensor connections next.

[RobG]

Just spoke with Dave, it was working when he bought the car, annd he has not had any problem with it. I'll check the bonnet sensor connections next.

Irrelevant. Alarm should still work due to sensors protecting other areas of car once alarm is set. Lock car with window open then reach in and wave your arm across the sensor field, if no alarm I`d check under scuttle to determine whether the horn & sounder are actually connected

[Shackeng]

Just spoke with Dave, it was working when he bought the car, annd he has not had any problem with it. I'll check the bonnet sensor connections next.

Irrelevant. Alarm should still work due to sensors protecting other areas of car once alarm is set. Lock car with window open then reach in and wave your arm across the sensor field, if no alarm I`d check under scuttle to determine whether the horn & sounder are actually connected

Next job, however, Dave assures me he hasn't disconnected it, and I believe him.

[Entwood]

Main alarm might simply have failed ... easy enough to test .. just whip it out and stick 12V across it .. no noise = fubared ..

Powersounder could have been failed for ages as it ONLY works when battery disconnected .. and how often is that done

If you want a hand looking at it, then I'm around tomorrow afternoon while I pack the 'van for me hols ... then away until 15th ..

[Shackeng]

Main alarm might simply have failed ... easy enough to test .. just whip it out and stick 12V across it .. no noise = fubared ..

Powersounder could have been failed for ages as it ONLY works when battery disconnected .. and how often is that done

If you want a hand looking at it, then I'm around tomorrow afternoon while I pack the 'van for me hols ... then away until 15th ..

Thanks Nige, but we're busy tomorrow, I'll have a look at it this weekend. Have a nice holiday.

[Brikhead]

I can't quite remember... are the indicators supposed to flash when the alarm goes off.

Powersounder could have been failed for ages as it ONLY works when battery disconnected

I DO remember that both the siren and the horn should sound if the alarm is activated.

[Jimbob]

yes, indicators should flash too 

[Bionic]

Even if the horn and power sounder are unplugged the indicators will still flash for a short while. The most likely cause is that the alarm horn (under the drivers side scuttle) has suffered the water bug of rust and it has seized! That is all it was on mine and a cheap horn from haflards at 6 quid solved the problem.
The power sounder only works when the main battery is disconnected and should not sound with the main alarm. All the power sounder is is a backup system should any idiot try to remove the main battery to stop the main alarm going off when they try to burgle the car. It senses that the battery has been disconnected and so activates itself. Problem is that the power sounders own internal batteries, which are not replacable because they are no longer manufactured or available to buy anywhere, give up the ghost and so makes the power sounder a useless item anyway. many oofers have simply unplugged it with no detrimental effects. As long as the horn that sits next to it is connected you will be ok. It goes off when the bonnet is lifted anyway so I cannot see the point of both. How the hell do you take the battery off without opening the bonnet anyway?
Hope that lot of waffle helps you understand a bit better.

[Shackeng]

Even if the horn and power sounder are unplugged the indicators will still flash for a short while. The most likely cause is that the alarm horn (under the drivers side scuttle) has suffered the water bug of rust and it has seized! That is all it was on mine and a cheap horn from haflards at 6 quid solved the problem.
The power sounder only works when the main battery is disconnected and should not sound with the main alarm. All the power sounder is is a backup system should any idiot try to remove the main battery to stop the main alarm going off when they try to burgle the car. It senses that the battery has been disconnected and so activates itself. Problem is that the power sounders own internal batteries, which are not replacable because they are no longer manufactured or available to buy anywhere, give up the ghost and so makes the power sounder a useless item anyway. many oofers have simply unplugged it with no detrimental effects. As long as the horn that sits next to it is connected you will be ok. It goes off when the bonnet is lifted anyway so I cannot see the point of both. How the hell do you take the battery off without opening the bonnet anyway?
Hope that lot of waffle helps you understand a bit better.

I think so, and is certainly worth looking at. A pity I had the scuttle off this morning, but didn't check the horn, only the pwer sounder, as I understood that they went off together so assumed that any fault would show up on both. The horn looked OK, but I will check it out now. I checked the voltages at the power sounder plug terminals which were:

Car unlocked and locked with bonnet switch made.
1 =0v
2 [ch8776] 6v
3 [ch8776] 6v
4 = -0.4v

No 12v or even close. :-?

Edit: I forgot to say that the bonnet switch plug was disconnected, but, as Rob almost said, reconnecting it made no difference.

[Brikhead]

The power sounder only works when the main battery is disconnected and should not sound with the main alarm.

Are you sure? I remember them both going off together when the alarm is triggered.

I'd check but my current Vx. is only an LS model...

[Shackeng]

The power sounder only works when the main battery is disconnected and should not sound with the main alarm.

Are you sure? I remember them both going off together when the alarm is triggered.

I'd check but my current Vx. is only an LS model...

Does anyone know for certain which is correct? As this may (should!) help me diagnose my problem. :-?

[Kevin Wood]

You should have ground, ignition switched 12v, permanent 12v and a signalling wire at the power sounder. I'd be surprised if any supplies have failed as I don't think they are even fused, save for one of the 80A fusible links.

Oh, and PM sent.

Kevin