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MG MGF Technical - Driver's window doesn't work anymore

Yesterday, I tried to pull down my electrical window on the driver's side of my 2003 mgtf on a parking lot and it went down, no problem.

However, when trying to close it again, it did not go up anymore. Damn, quite cold during winter days :-)

I tried to exchange the switch with the switch on the passenger side, but still same problem. So it was not switch related.

I disassembled the whole window mechanism to check whether my elect.window motor was broken. But it did work, but only in 1 direction (downwards)

So I suspect this is an electronical issue (ECU)

Could it be that one of the ECU ports is faulty and
what can I do to fix this ?
Is this a separate ECU like the MGF ?



You need to check for voltage to the motor with a multi-meter or a bulb. If you have no voltage, then it is probably a cable/switch fault, or the single push open/close control.
To check the motor, hard wire it direct to the battery.
Geoff F.
Geoff Farthing

If the TF is identical to the F, there are seperate fuses for left and right windows in the fuse box below the steering column, pays to check these first before taking the door to bits to change a "broken" winder motor.
A M Cox

I first checked the fuses : but they all seem to be OK.

I also reversed the motor cabling to check if it was a problem with the window motor, but it also turned the other side so that gives me only on other option :
how do I switch (internally) the cabling from the right window control (= good window) to the left window control (=bad window, that only operates in 1 direction; now it only goes up since I reversed the cabling of the window motor)

Is there a possibility to switch left and right on the control box ? I know that the control box is situated at the back of the dashboard console on a MGF. But where is it located on a MG TF ?????

Hi Gerrit,
Having read theposts to your problem, your window motor sounds as if it's ok. However I suspect that you have a broken wire somewhere. I will need to look at Dieter's website to refresh my memory as to how the wiring goes. Have you looked at his website?
W A Nixson

Hi Gerrit,
Have a look here: -

As you can see the motor is wired to the common connections of a double pole double throw switch with a bias of centre off. As the motor runs in only one direction the fault has to lie at the plug in the back of the switch where the crossover connections are. I.E they change over the motor terminals between 12-volts +ve and earth to either drive the window up or down.

Either a broken wire or one socket is not fully home in the plug and thus not connecting to the pins in the back of the switch.

A multimeter on the switch plug terminals as you operate the switch in both directions should enable you to diagnose the fault.

Hope this helps.

W A Nixson

Wow, many thanks. That will certainly help me to diagnose my problem and find out where the line is broken :-)
I'll keep you posted

best regards

Apparently most electrical schemes are just for MGF/TF till 2001. Apparently mine (year 2003) has quite another configuration for the ECU Window control unit. Normally it can be found at the footwell at driver's seat. But no luck for me.
(YWC106170 - Control unit electric window lift-one touch (at lower A-Post) only for MGF/TF from VIN= YD511059 till VIN=4D620548)

My VIN = 4D623016...

Can anybody help me finding the Window-ECU on my MGTF 2003

This may well have been deleted as MGR Cheapened/ Reduced Production costs for the car.
Geoff F.
Geoff Farthing

Hi Gerrit,

At VIN 4D620458 there had been some major changes as introduction of MINI-relays on the Fuse panel.

:-) Cost reduction of course.
I have no idea about more details.
Did the one-shot feature work before the whole thing failed ?
If so then there may be another ECU, presumable behind the fuse panel.
(Former MFU (multi function unit))

However, all guesswork. I'll ask at out German Forum. and get back later.

Hi Gerrit,
That is a real shame about the change in the window control for your car.

However, did you at least check that is was not something simple as I mentioned earlier with regards to the wiring into the back of the switch?

Even with an ECU I would expect you to find that 2(outer) terminals will be at 12-volts and the other 2 at ground. The central terminals should have the motor connected to them.

Good luck.

W A Nixson


I know for sure that the problem is at 1 of the 2 output terminals of the ECU, since 12V is measured at the switch on both input terminals but only 1 path of these output terminals feeds the motor (measurement done at motor side).

This can only mean two things :
1. or there is a broken cable/connector (from ECU to motor)
2. there is a faulty port on the ECU (internal malfunction)


Indeed something has changed after VIN 4D620458, since
I bought some online technical documentation for all MGTF models. But when looking at the technical photos of the location of the ECU, my MGTF did not correspond to these photos. Normally on a LHD MGTF you should see a little black box at the lower left foot well at the driver's side (behind carpet)

But instead, nothing found and the 2 holes for fixing the ECU where covered by black factory stickers.

Already thanks for your help. I hope you will find something because I'm in a dead end now :-)


Hi Gerrit,
Can I make a suggestion? It is this - ignore the ECU.

Make sure that the motor terminals come directly to the cental terminals of the switch. You say you have 12-volts at 2 terminals of the switch and they should be diagonally opposite each other. The other 2 (diagonally opposite again) must be wired directly to ground. You will now be able to operate the window both up and down but you will not have any special features. The operation will be as the early F's. I hope this will at least get your window functioning in both directions until you can resolve the ECU problem. Disconnect wires to the ECU and re-wire as needed to achieve the above.

As an after thought, your passenger window is fine. You may want to swap over window control at the ECU between the driver's and passenger window. If so, at least your main window will function as normal. It's difficult to advise further without seeing the car.

Good luck.
Hope this helps.
W A Nixson

Thanks W,

I was thinking the same way for solving my problem more quickly instead of trying to fix the ECU :-)

I'll try this. I'll keep you informed.



apparently the ECU has been replaced by just fuses...(it was the case for late MGZR & ZS)..since I did not found any ECU behind the dash, only the EPAS ECU.


You need to remove the switch and clean the intrior of the switch where the two rocker points come in contact.
Be careful not to lose any of the small parts.
I have this problem at the moment and will have to clean mine soon as the right hand switch is working at thwe moment.
Good luck.

I found the control unit of my electr. windows : it is the unit YWC001540 from Pektron. A plastic black box behind the central console.
One major problem : this box consist of a circuit board with transistors and relays, but also controls the alarm functions.....
So just replacing this box could mean that my car wouldn't start without the proper programmed keys.

Has anyone have an idea how to proceed ??

Later TFs changed to the SCU system which is a body control unit covering many functions including security and windows etc.

The problem for owners with cars running the SCU when things go wrong is that they have a once only security coding that unlike the previous Lucas 5AS security ECU it can't be recoded to any other car, not unless the engine ECM and fobs (the round once with the MG motiff in the centre come with it.) are renewed or replaced as a complete set from another car.

I have seen failures in the on board relays affecting late ZRs window operation and this is likely to be the same problem. I have also seen a pal carefully canabilise the broken SCU by using a functional relay removed from a spare SCU and transferred onto the broken SCU board. This doesn't impinge on the security programming and negates the need for T4 diagnostics as the only common diagnostic system with the access to be able to programme late TF, ZR and ZS models with these SCUs and identified by the round fiob with central badge.

The alternative would be to renew the SCU, and if my memory serves me correctly that also demands new fobs too. Original fobs once they have been used more than a handful of times pass an inbuilt restriction on reprogramming. So only it the second spare fob (all cars had two from the factory) and it had only been used a handful of occasions could this be reprogrammed.

For SCU repair have a word with Nick at an enthusiast of huge skills that has seen him set up his own self and wife business in the pleasant fields of Staffordshire, near Burton on Trent and conveniently for me is quite close.

Roger Parker

EXACTLy The same thing apend to me, in both windows, in my case was only the bottons, i clean both of then and the work fine .

sorry my english :)

This thread was discussed between 03/01/2009 and 30/01/2009

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