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MG MGF Technical - Window Lift Relay

I've been looking at the F's electrical schematics and have noticed the 453 window lift relay. Does anybody know what this does and why?
As far as I can see, all it does is stop the power to the window switches when the ignition is off but I can't see any reason why this should be.
I am thinking of bypassing it but i feel there must be a good reason for MGR to bother to put it in.
Any ideas?

cheers
Darren
D Edwards

I think Thatcham security terms may be the reason.

I did a bypass to my cars relay (Wired 'OR' with two diodes). It is controlled by MEMS-timer. This allows to operate the windows for about 3 minutes after ignition off.
Carl from Sweden found this option years ago:
http://www.mgfcar.de/power_delay_by_carl/

Not sure about the mgtf options. I think it's included now ??

HTH
Dieter
Dieter K.

MY2000 MGFs and TFs all have the 'delay power off' system to allow the windows to be closed after ignition switch off.

Which reminds me, I really must get around to performing the mod myself - I've had the diodes sitting on my desk for literally years meaning to do it!!! LOL
Rob Bell

If you have the window switches operative when the car is locked a thief can push a thin stick past the window seals and operate the windows.
Bruce Caldwell

Bruce,

I think it's time now to introduce the easier 'Bruce-Power-Delay-Solution' and Rob can leave out the diodes
:)

-- cut from Bruce Email---
..would it not be easier to simply remove the Light Green (LG)
wire from the Window Lift Relay and connect a wire from the Brown/Pink on the
MEMS Relay Unit in its place? The Light Green wire could then be isolated
with insulation tape. In this way, no diodes would be required. Why use two
supplies for the relay when one would do?

The Window Lift Relay would then be powered by the current from the MEMS unit
alone.
-- end ----

:o)
Seams to work, does it ?
Dieter K.

Works for me!

Bruce
Bruce Caldwell

Hmm, well that should certainly work - nice one Bruce. :o)

I assume that the current draw from the window lift relay is very low, and therefore will not cause issues with the MEMS? Does the circuit remain 'live' at all times whilst the ignition is on?
Rob Bell

>Tja, Kempenrit war super! Hast Du Dein mehrseitiges Entschuldigungsschreiben schon vorbereitet?

Yes, of course and the currency only needs to drive the 'tiny' window main relay.
Haven't looked from where the brown-pink gets power, but it's NOT direct a MEMS output. Brown-Pink is switched from relay contacts, is it ?
http://www.mgfcar.de/power_delay_by_carl/mems_mpi1_t.jpg
Dieter K.


Hi all,
the main reasons for the original 2-diode system was the following:
1. The diodes prevent any currents going backwards in the system, i.e. make a "false" connection between fuse 18 and fuse 2. It makes an "OR" circuit for the current feed in this way.

2. If so needed only a cut out of the diode from MEMS relay is needed to restore to originallity.The series diode then left in the system wonīt hurt anything.

3. Of course Bruceīs system works also as far as I can see in the drawings - so it is really a matter of taste wich alteration one prefers...

And so for something totally different : Highlighted in another thread IT CANīT BE STRESSED TOO MUCH THAT ANY CAR NEEDS A SEPARATE ANTI-THEFT DEVICE SUCH AS A HIDDEN SWITCH TO IGNITION OR FUEL-PUMP !!
Yes, I do shout about it . But belive me , as owner of an old SAAB that anyone can get moving it is found during the years that this small item is now-a-days a must ! For the beloved "F" it is a hidden switch in series with the inertia switch....

BR, Carl.
Carl Blom

Cheers,
I have read up on Carl's design but I was thinking that this seemed a lot simpler.
so, can anybody say for any certainty that Thatcham is the reason? it sounds plausible though tbh the least of my worries is somebody poking a (v long) stick through my window.. if they are that determined then they'll also cut a hole in my roof!

Following on from Carl's comments.. does anybody know how difficult it is for a thief to get past the immobiliser??
D Edwards

See the thread in the MGF General Section on 'Security Fault in TF' then take Carl's advice.

Bruce
Bruce Caldwell


Hi all,
Those who are "dedicated" to one make only, say BMW, carry their own fully compatible "plug in" system on a bread-board. This is at least the way many fine and expensive cars "go East" from here....This is why it is so essential to have something totally unexpected in the car as an extra small switch for the fuel pump.Dont try another additional commercial alarm as they all are well known how to by-pass ! If they for any reason get stuck longer than expected in the car not getting it to start they just bail out and try the next one in the area on the list kindly provided by the authorityes ! Over here they have a time at the ferry-terminal to meet so any delay is then bad news...

BR, Carl.
Carl Blom

>does anybody know how difficult it is for a thief to get past the immobiliser??

There are only a finite amount of points where you need power in the engine, a replacement ECU
would get past most of the issues. I agree with Carl, but a system which alowed the fuel pump to run for about 60 seconds before cutting out would be better. I did think about re-useing an old pager to do this for me, but that was just another one of those idea's which is filed away for more important stuff to happen first.
Will Munns

This thread was discussed between 23/08/2002 and 27/08/2002

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