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MG TD TF 1500 - #1 Blue Ignition wire

All:I am getting ready to put the wiring harness into my TD. I bought the Moss harness for the cars with no turn signals. One small problem.. There is no #1 Blue wire included in the harness. This wire goes from the "IG" terminal on the Ignition/Lighting switch to the "A3" terminal on the Fuse Box. Am I missing something here? (Besides the blue wire).

Anyone else ever run into this?


Kevin G

I just ran into a similar problem on a TD wiring harness that I was refurbishing. It had a replacement Moss harness. It is due to an error in the wiring diagram in the Shop Manual. The blue wire you are looking for is really a white wire (number 9). All the wires that come into or leave the A3 terminal are white and there should be three all together.

The previous owner of this TD actually added a blue wire outside and along the path of the harness from the fuse block to the instrument panel. When he discovered he had an extra white wire at the fuse block he simply taped the end and left it hanging. It took me awhile to figure out what happened. Look closely at all the various wiring diagrams in the book and I think you'll reach the same conclusion.

Good luck,
Roy Challberg


In addition--

The wiring diagrams in color, published in the Sacred Octagon (NEMGTR) show the wires as white (or actually tan which represents white on a white background). They recognized this error in the original wiring diagrams. But be careful the color diagrams do have other errors that could cause confusion.

Roy Challberg

I agree with Roy's comments,,, Where are you located in Ct ? We could use another TD owner in the CT MG Club !!

Steve Wincze

Thank you to all. I will look in the back TOS's for the appropriate wiring.

Thanks again


Kevin G

errata: TSO's
Kevin G

The problem is not so much an error on the original wiring diagram as it is that sombody positioned the #1 that belongs to the headlight wire coming from the H terminal on the ignition/light switch where it can be inturpeted as applying to the wire between terminal IG of the ignition/light switch and fuse terminal A3. If you look at the other terminals that have multiple wires on them, you will see that the color number is only listed once (ie. terminal T on the ignition/light switch shows color number 41 for all 4 wires to it. likewise on terminal E of the regulator has color number 57 for all 3 wires on it. and fuse Terminal A3 has has color number 9 for all three wires on it.) Following this pattern, the color number 9 on terminal IG of the ignition/light switch applies to both of the wires on it, while color number 1 only applies to the wire going to terminal T of the ignition/light switch. The positioning of this number causes it to be somewhat ambiguous, along with the departure from only nmbering the wire at one end and having another 1 placed next to where the wire connects to the common terminal of the dipper switch. Cheers - Dave
David DuBois

Hi Kevin,
Great minds think alike;) I'm getting ready to rewire my TD too. I ordered a sub harness for the dash from British Wiring. It includes the red and white going to the dash lights as well as a blue wire and several others.I ordered the bullet clamping tool as well. It works great.
paul valles

I had come to the same conclusion that Dave D did when I was working out my wiring plans for my panel. At the time I spent several minutes scratching my head!

Dave Braun

This thread was discussed between 17/02/2007 and 19/02/2007

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