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MG MGF Technical - Boot lock-Alarm.

Having a browse through the owners manual it says when opening the boot (alarm on), the alarm is deactivated by the key, and re-arms when boot lid is closed!.

If I open my boot with key without unlocking with remote first, the alarm goes off!!.

Have had a multi-meter across the micro switch on the lock barrel and all is ok!..... I assume then the boot lock itself is not sending the message from the micro-switch to the alarm ECU!.

Does anyone know (or a picture link), how the boot lock mechanism relays the message/s to the alarm ECU

Mark.L

Mark,

I had the same problem for last couple of years (boot alarm worked as you describe originaly).

However, on sorting out a recent battery drain problem, after dicovering the boot light being on all the time, I found all but one wires were severed in the boot wiring. After rejoining the damaged wires my battery drain problems were solved along with the boot alarm prob as well.

You may have just one or two wires damaged and which may maybe making a contact when closing the boot lid so that all looks well.

Steve
Steve_P

Thanks Steve.

Was thinking the old loom and boot hinge problem, just wanted to see if it could be anything on the lock mechanism itself, before I start ripping into the loom wiring!.
Mark.L

There is a micro switch on the key lock. This is unlikely to be problem however I have one in the garage safe should you need one.
The harness has a split convuluted tube wrapped around by teflon tape. Careful removal of the tape enables the cables to be examined. I use 2mm crimp sleeves and shrink tube to repair.
Geoff F.
G. Farthing

Thanks Geoff.

The micro-switch on the lock barrel was the first thing I checked, but metered out ok!!.

The flying lead (2 wires) which connects to the lock barrel, connects to the boot latch mechanism, before heading back into the loom, thought I would check this first before attacking the boot hinge wiring!!.
Mark.L


My alarm goes off if I open the boot with the key without first disabling the alarm via the fob.

I personally prefer this.

The only semi-secure place in the F is the boot, if you can access the boot without the alarm going off the alarm isn't really much use is it ???

Stu
Stu Dickens

Got a Good point there Stu,often wondered why my alalrm doesnt go off when open boot also, Dave
DC Morris T6 DCM

The alarm will trigger if the boot is opened by any other means other than via the lock though...
Rob Bell

a related question, on the drivers door, where is the switch that detects that the door is open for the alarm and light function?

Is it integrated in the lock mechanism there as well?
O Sander

Stu

>> I personally prefer this <<.

TBH so do I!!, My F has allways been like this, and I thought thats how it was supposed to be!......... till I read the Manual!.

The fault may indicate the common wiring loom/boot hinge problem that many Fs seem to suffer, If one of the wires has snapped in the loom, then there is a good chance some of the others will follow suit causing other more serious problems!!.

Ignoring there is a fault because we prefer it that way may just be building up more (and expensive) faults for the future!!.
Mark.L

>> a related question, on the drivers door, where is the switch that detects that the door is open for the alarm and light function?

Is it integrated in the lock mechanism there as well? <<

I was looking into this as well with a mind to install a window-drop and raise function when opening/closing the doors. Unfortnately, the workshop manual doesn't provide a definitive answer to this particular question, however I suspect that the lock mechanism does perform this fuction. The way to confirm is to look at the two multiplugs that insert into the lock mechanism and look for the purple/slate grey or purple/white wires that control the intertior light operation along with the perimetric alarm circuit.
Rob Bell

O Sander

Yes its in the door lock mechanism, it controls the alarm and the lights in the cabin.

Oftem if you get alarm problems when the car won't lock properly (not the boot, the boot is usually the purple wire broken) its the door lock and you need to buy a new lock/ striker mechanism


Brian

>>Ignoring there is a fault because we prefer it that way may just be building up more (and expensive) faults for the future!!<<

The loom/hinge syndrome caused my battery drain problem (I bought a replacement because I thought it was U/S). So if your boot alarm dosn't work as it should, this may possibly be a prelude to further problems as Mark suggested.

Steve
Steve_P

Brian,

>>Oftem if you get alarm problems when the car won't lock properly (not the boot, the boot is usually the purple wire broken) its the door lock and you need to buy a new lock/ striker mechanism


So you're saying that the fact that an idiot ruined my door lock with a failed brake in attempt and the fact that the cabin ligt comes on sometimes when the door is closed (flat battery) are the same problem.

Cheers
Oskar
Oskar

Mine started doing the same recently. I suspect its the battery in the key fob thats going flat. I'll try my spare key when I get home..

Jason
W681 JCB
Jason Ratcliffe

The alarm went off with the spare fob as well. Either my theory is wrong or both batteries need replacing at some point :(

Jason
W681 JCB
Jason Ratcliffe

This thread was discussed between 28/08/2005 and 30/08/2005

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