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MG MGF Technical - Help - my alarm is annoying the neighbours

Not sure if anyone can help. The alarm on my MGF has a habit of going off at night for no reason. Doesn't do it during the day, only at night and enough that everyone down the street is beginning to hate me!

Anyone know if there is a specific reason, is there anything I can do to adjust the alarm or can a dealer do anything to solve the problem? Otherwise I am going to have to work out a way to lock the car and leave the alarm off.

Thanks
Daren

Do you perhaps leave your mobile in the car at night, as the alarm is known to be triggered by this.
Another possibility is a faulty connection in a door lock or corrosion in one of the locks, as you can find in the archives.

The dealers can adjust the volumetric alarm, don't know about the door alarm.

Johan
Johan Slagter

Thanks for that. Sorry to ask a dumb question - going through the archives now. Don't leave the mobile in the car though. Am beginning to get nasty notes left on the windscreen - so better sort it out!
DE Rudd

Taxi's (or rather their radios) set mine off on the odd Saturday night someone gets a cab home. Could be this?
Leigh

Daren,

Try "normal" locking - only one press of the blipper. This doesn't disable the door locking buttons, but I believe also doesn't enable the volumetric sensor. If the alarm still goes off, you know it's the perimeter sensors (doors, bonnet and boot). You could also try the alarm test mode:

Close all the doors, bonnet and boot.
Sit in drivers seat, close door.
WITHIN 2 SECONDS:
Press the driver's door lock button.
Turn ignition on, then off, then on.
Raise driver's door lock button.

The immobiliser buzzer will now constantly sound. When any of the perimetric sensors are activated the alarm light on the dash will come on for a second (try opening all doors). If you press the blipper unlock button a few times, the volumetric can also be tested - every time it detects movement the light will come on.

Turn off the ignition to cancel test mode.

HTH,
Tim.
Tim Jenner

Before I got my MGF I had a land rover freelander and I believe they have the same alarm System as the mgf well I h ad the same problem with the alarm going off at night so I took it back to rover they told me it was a common fault on the alarm system and that it was triggered by the “gravitational pull of the moon” now I think this was a load of rubbish and they where just trying to cover for crap build standard of the freelander but then it maybe the answer to your problem
David Smith

“gravitational pull of the moon” is the best one I've heard so far.

When my alarm started playing up in a similar manner it ended up as a defective door lock (probably the ubiquitous micro switch) - a quick replacement fixed the problem.
JohnP

I Blame al-Qaeda

Although a spokesman said 'they are finding this tactic in effective'...

(Well they get blamed for just about everything else!)..

Stu

One other avenue to explore - Baby Listeners, as a lot of these are 'wireless' that means they use a low power radio transmitter/receiver BUT they can be picked up from quite some distance and when I have my 'Bike to Bike' transeiver activated I have had some interesting 'messages' specially where Mum & Dad share the same room as Baby and they forget to switch off when they go to bed.......

I dont know if these can 'set-off' the alarm but I have heard that garage openers can and they use the same wavelength.

Ted
Ted Newman

>>I dont know if these can 'set-off' the alarm but I have heard that garage openers can and they use the same wavelength.

And microwaves apparantly.
Steve White

I thought the alarm was set with one blip. Two blips double locks the car. If you want not to set the Volumetric alarm you need to lock the car with the key.

Steve.
Steve

Daren,

I have exactly the same problem as you.
The alarm behaves perfectly during the day, also bhaves perfectly if the hard top is on.., but if I have the rag top up and its the early hours, then my neighbours get the good news.
My theory has been that its something to do with the air presure making the windows pop in/out slightly..

I live in a quiet street so you can rule out other cars..

Does anyone know.., Is there anyway to turn down the sensitivity?
Neil H

The sensitivity can be adjusted by Testbook. I don't think the windows moving will set the alarm off, after all it's designed to work even with the roof down!

Tim.
Tim Jenner

there is a way of locking the car without setting the alarm, drop me an email if you want to know how. (don't want to broadcast it all over the internet)
ricky

I have the same problem.

I tried disconecting the volume sensor and this did not work.

I once had it diagnosed by MG who plugged a computer into my car and read which sensors caused the latest alarm. The result was that each time it was a different sensor.

I now have my horn disconected.

I have a wiring diagram to try and decipher which wire to cut so that when the alarm goes off it does not send the signal to the horn. As I understand it the wire I have to get to in on the right hand side up behind the dashboard and requires taking the dash out to get at it.

If anybody has a solution please let me know.
John

John,
If you are really sure you want to do this....
remove driver (for forign) side kick pannel (the one with a light in) locate loom comming from back of Alarm ECU (is under radio has ariel wire Yellow comming out as will as many other wires)

Find purple wire with black tracer, snip but leave enough room on both ends to fit bullet connetors, fit bullet connetos but don't plug them into each other. This way you can 'undo' the work when you find the real cause.
Will Munns

Hi Will,

great advice. This is really a big help. This way I can have the alarm set (for anti theft) but not have the horn go off for every cat on the roof / taxi / moon phase etc.

I will contact you tomorrow when I have looked at it.

Very many thanks
J
John

John, the immobalizer is set after you turn the car off, it is independant of the alarm for turning on, but you use the blipper to turn it off, same as locking the door with the key and unlocking with the blipper.
Will Munns

But with this method he can also have the superlocking without the perimeter detection.
Leigh

Very true, but if a dodgy door sensor is kicking him, then it is only time untill it dies for good and then superlocking won't work either.
Will Munns

Will / John,

>>This way I can have the alarm set (for anti theft) but not have the horn go off for every cat on the roof / taxi / moon phase etc.<<


Surly the whole point of setting the alarm is that is someone breaks in the horn sound to draw attention to the thief. If the horns are disconnected it's a waste of time setting the alarm.
David Clelland

Or it could be a cat jumping on the roof setting off the volumetric sensor.......
Mark P

This thread was discussed between 21/06/2003 and 01/07/2003

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