PROBLEMS WITH F ALARM AGAIN!!

[arsvs]

OK,
i know this has been the bain of most f drivers and ive been all over the net and back again to find the solution.
As everyone else my alar goes off when it wants to mostly though when i double click the button it goes off straight away, but then again it might go off hours later.
after having the boot loom fire all the wiring has been replaced by myself using very well insulated wire so no probs there.
both doors turn the courtesy lights on when opened,
both pins go down when locking,
i disconnected the courtesy light switch under thew front hood.
fully charged my battery (although this may still be a problem as when i had the fire it did kill it)
unpugged my stereo,
did the alarm test,
unplugged sensor in the t bar,
and checked the battery earth strap and cleaned it.

right all that disconnecting hasnt done a thing it still goes off ive come to unplugging the horns now but thats never good is it?
i dont have the money to get it plugged in to the computer so pleeeeeease help me.
pm me if there is anything you could suggest that would comprimise the security of everybodys car on here.
thx guys

[Charless]

A previously run flat battery (fluctuating internal voltage) will probably always be a weak link. AFAIK nobody is holding back a silver bullet answer. Some of them just do that until you find it and fix it. The boot hinge wiring was a good start.
The unplugged horns are a good intermediate 'fix' to keep the peace with the neighbours!
In five years I have had very little problem from early Fs, but I never deadlock and do regularly spray lubricant all over the door central locking motor/door microswitches and the bonnet switch.

[Phil MGFPM]

Have you removed and cleaned up the bonnet light switch. My F was intermitantly alarming esp when there was a wind, and after 2 years (unaware of the link between the bonnet switch and the alarm) traced it to an oxidising copper strip on the bonnet switch. It is now completely reliable. May be i was just finally lucky in tracing it. Phil

[arsvs]

hm left it last night not a problem.
went to my mates house armed it with 1 click and beep beep beep beep!!!!!
i have completly disconnected the bonnet switch soooo???
wd40 all over the door straps and door locks.
ive got a 59 plate astra with a virtually brand new battery so ive swapped them over to give it a try.
20 mins and no alarm yet, will post later when it goes off again ):
its such a pain guys.

[Mark L]

Most common 'false' alarm problems are either....

1:Interior Volumetric sensor

2:Boot loom hinge wiring

3: Door lock microswitches

If you say you've checked 1&2 then 3 is the next place to start.

There is a microswitch which is part of the door lock solonoids, water/damp can enter these causing corrosion to the switch leading to false alarms. Sadly these microswitches are part of the solonoid motor itself and thus requires the whole unit to be replaced.

[arsvs]

@ mark l
just checked 3 unplugged passanger side ,, alarm went off,,, unplugged deiver side and silence until i put the key in the ignition and beep beep.
so looks like its the drivers microswitch.
do you know if these can be cleaned and tarted up as i did have problems with the window switches and i just cleaned them.
also are the solonoids just for the mgf or can i get down the scrappies and get one off a 400 or something?

[Mark L]

@ mark l
just checked 3 unplugged passanger side ,, alarm went off,,, unplugged deiver side and silence until i put the key in the ignition and beep beep.
so looks like its the drivers microswitch.
do you know if these can be cleaned and tarted up as i did have problems with the window switches and i just cleaned them.
also are the solonoids just for the mgf or can i get down the scrappies and get one off a 400 or something?

You could try cleaning up the switch contacts with a WD/electrical contact cleaner type stuff, but from past experiance (myself and others) the only real cure seems to be a replacement, unless you are somehow able to strip and replace the switch.

I think the solonoid is pretty unique to the F/TF, so I doubt other MG-R models are the same.

[arsvs]

yes thought so trust rover(:
just looked on ebay and there are none on there at all and the only rover breaker round here seems to never have ant f/tf in at all.
ive plugged everything else back in including the n/s door and everything seems ok now.
i think ill take it off tomorrow and take a look if i cant do anything with it its not really a hardship to use the key to unlock the car is it? until i find one.

[Charless]

Over on .org there is a how-to somewhere with the central locking motor unit disassembled and showing the microswitches which can be replaced. I think a company called Cherry supplies them, Dieter mentions it on his site too. You seem happy with doing the nitty gritty so this might be your best and certainly the cheapest option. Let us know how you fare if you do! HTH

[arsvs]

ive decided to buy one from ebay £9.99 its from a 2009 tf so might last a couple of weeks (:
i think when i take the other one off i'll strip it down so if i can find an easy fix at least i can post it on here and save some people some money.
i'll take a look at all the components if i can find that charless thx.

[arsvs]

right then replaced the door catch and no problems with the alarm at all.
if anyone is having problems i would suggest (if you cant get it plugged in to a T4) disconnecting each alarm component in turn and seeing what happens.

[Rob Bell]

Glad you got it sorted

Bless those little micro switches eh?

[Flat Eric]

Hi there,

New to the forum and now the owner of a Mk1 F. Been a challenge but got most things sorted out BUT I am having problems with the alarm/courtsey lights.

I guess its the micro switch having read this thread but would appreciate any thoughts before I go an buy a new door catch.... In short when driving along the courtsey lights will come on when they feel like it. When setting the alarm I can sometimes get the alarm beeping at me when I lock the doors with the remote AND the courtsey lights can sometimes stay on after the car has been locked and alarmed!

Ive taken a look at the electrical connections to the door catch on the drivers side and cleaned/reseated the connectors but this has not sorted the problem. Any advise before I go and buy another donor catch would be great.

Many thanks!

[Rob Bell]

It may be possible to disassemble the lock mechanism, give everything a good clean and reassemble and make the problem go away - but unsurprisingly, there's no guarantee that that will work...

[Flat Eric]

Hi Rob, Thanks for the advise, will give it a bash!
Thanks,
Stuart.