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MG MGF Technical - Alarm sounds if you don't exit quickly enough

Has anyone experienced the following symptoms with their F alarm and is there a cure?

Turn off the engine, get out of car and lock with blipper BEFORE the dashboard immobiliser LED starts flashing and I'm ok.

However, turn off the engine, get out of car and lock with blipper AFTER the dashboard immobiliser starts flashing and the alarm will sound some 30 seconds to 30 minutes later. It resets itself and sounds again 30 seconds to 30 minutes later. Unlocking, then locking the car again doesn't always stop the alarm from sounding again.

Only seems to happen after the engine's been running, ie all fine if I unlock and relock the car after it's been standing for a while. Also possibly worse in cooler outside temperatures. Happens everywhere, home, town, work, country.

Any clues? Grateful for the advice.

Paul Bevan

Sounds like you have a sensor or sensor wire on the way out. The flashing light is almost defo nothing to do with it.

First thing to check is the wireing as it goes over the boot hinge, if this is not at fault then the next suspect is the door locks - do the interior lights light up when the alarm goes off?
Will Munns

Haven't noticed the interior lights coming on but will check. Supposing they do/they don't, what would be sensible to check next?
Paul Bevan

I would say probability:
85% boot wire failure
10% door lock failure (usually replaced for another reason before alarm)
2% boot lock failure
2% bonnet catch failure
1% other

Unless you changed the radio recently, in which case you might have chaffing wires behind the radio console.
Will Munns

Thanks Will, I'll tackle in the order you state - fingers crossed I don't get down to the 1% other!
Paul Bevan

BTW Will, forgot to mention all ok when locking car with key - not sure if that affects your probabilities?
Paul Bevan

Locking with a key does not set the alarm.
Will Munns

Ah, I thought it set the alarm minus volumetric sensor?
Paul Bevan

Do you have a second system like Tracker fitted ?? It can "Fight" the MG System.

The Dealer in conjunction with MGR spent two days attempting to overcome my alarm sounding after 13 seconds including changing all units with a showroom car. They concluded that it was caused by the Tracker.

The Tracker dealer disconnected the battery, waited for 1/2 hour, reconnected the battery to reboot the system and "Hey Presto" No problem. The system is a computer and what do we do when our computer plays up.

Rather than chase your tail all day, call your Dealer and ask for a price for a Textbook System checkout.

Geoff F.
G. Farthing

Geoff - time is money so testbook hook-up may be a wise move...
Paul Bevan

>The system is a computer and what do we do when our computer plays up.

We identify the problem, report an error, trace the bug and fix it.

Then we log the bugfix and contact the affected customer and release them a patch. Other customers get the bugfix immediatly if they come accross the problem and if not it is incorprated in the next release of the software.

We _don't_ blindly ignore the bug and hope it goes away when the wind blows in the right direction - this is at best a temporary masking of the problems.
Will Munns

Will,
You are right for the IT World, but in the Real World, we just Reboot and live trusting that it does not reoccur.

My fault first occured at exactly mid-night on 31st May 2002. We attributed it to a spurious radio signal possibly from a tele meter reading transmission.
Nothing else was done and it has been perfect since.

Geoff F.
G. Farthing

Automotive software is one of the most highly tested and stringent software arenas. This is because faults here are easily traced to a provider, and the system finds its way into literally millions of vehicles. Also many automotive systems are life threatening if they were to fail - and generally the same people and requirements are enforced across the platform.

Almost always when a fault shows up in the automotive systems it is due to a problem elsewhere.
You have two incompatiable systems (one of which is aftermarket and so not designed to the same quailty specification)- and for now you are 'lucky' in the lack of reoccurance.

For systems designed to work together software bugs are very few and far between.
Will Munns

B&G confirm Testbook alarm logging came into being from 98 model year on. Mine's a 97...
Paul Bevan

This thread was discussed on 01/09/2004

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