MG F/TF Boot Hinge/Lid Wiring Loom Inspection Guide

Due to opening and closing of the boot lid, wiring loom attached to boot lid is folding every time. This folding can eventually lead to breaking of wires within this loom. This breakage can lead to various type of problems from non-operating third brake light to alarm sounding during night.








It is wise to make inspection of this loom in order to see if you have broken wires and you need to repair them.

When repairing them, it is wise to make them tad longer then before, as this will allow more easily folding space thus making breaking less likely to occure next time.

Following is list of wires that are passing to boot lid, for you to be able to identify them.


MG F/TF Boot Hinge Wire Colours & Functions:
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Mk1 MG F has 8 wires in this loom

Black ............................... 0,5 mm² - Boot Lid Switch - earth wire
Purple/Red .................... 0,5 mm² - Boot Lid Switch (when switch is closed this wire is earthed)

Black ............................... 0,5 mm² - Boot Lock Switch - earth wire
Black/Red ...................... 0,5 mm² - Boot Lock Switch (when switch is closed this wire is earthed)

Black ................................ 0,5 mm² - Third Brake Lamp - earth wire
Green/Purple ................ 0,5 mm² - Third Brake Lamp (when brake switch is closed this wire is live)

Purple .............................. 0,5 mm² - Boot Lamp - live wire
Purple/Red ..................... 0,5 mm² - Boot Lamp (when Boot Lid Switch is closed this wire is earthed)

NOTE: Purple/Red wires of Boot Lid Switch and Boot Lamp are joined in the loom within engine compartment when they pass from boot lid.

Mk2 MG F and MG TF have 7 wires in this loom

NOTE: Boot Lid Switch earth and Boot Lamp earth wires are joined in the Boot Lid






Note that if you have broken wires at folding area and among broken wires are earth wires of Boot Lid Switch (Load space switch) or Boot Lock Switch (Tail door open switch), since these earth wires are coming from the earth header joint from picture below, whole earth header is/might be compromised. This means that all circuits listed on the picture might not work. Since among them is Fuel tank unit, you might not be able to start the car.





If among broken wires is Third Brake Lamp (High mounted brake lamp) earth wire on following picture you see what other circuits are connected to same earth point, which will/might not work due to this break of the wire.







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Roverlike . Well done for this , very impressive .
John .

I found this thread very useful today and found that all my wires into the boot loom were broken, I am confident with these well written instructions that |I will be able to repair it easily, thanks 

It doesn’t matter how far down the track we are, posts like this from Roverlike are probably of greater value now than when originally posted.
I have frequently commented on spurious alarm soundings & there in the first paragraph comes the echo of those comments.
I thanked our friend then & I do so again now.
M