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MG TD TF 1500 - Wiring help please.

I bought a new wiring harness some months ago to rewire my 1950 TD
fitted with a 9 post regulator-- as opposed to the 5 post regulator and
separate fuse box. I fitted the harness to the frame and have started to
wire up the regulator. I have hit a problem. I have a brown 28 strand wire
and nowhere for it to go! If I had a 5 post regulator and fuse block I would attach it to post A1 on the fuse block.

Here in the UK it seems you can only buy two types of harness.One designed for the dash dipper and the other for a floor dipper. Although the 9 post and 5 post regulators have different wiring diagrams, the harnesses seem to be the same.

When I ordered my harness I specified it for a 1950 car with provision for
flashing indicators. Every thing seems to fall into place beautifully except for this bloody brown wire. The obvious answer is to ask the man who made it for me. I can't. Sadly he has died.

What should I do? Is there a post for the brown wire or should I fit a 5 post regulator and fuse block or have a new bespoke harness made. Surely I'm not the only one to have had this problem.

Many thanks
Lionel.
L.F. Thorne

Lionel, the WSM Wiring Diagram for a car with a 9 post regulator (N.21) shows that a brown wire goes directly from the hot side of the starter switch to the ammeter. In fact, all TD wiring diagrams show this same brown wire connection. The 5 post diagram shows an additional brown wire going from the starter terminal to the A1 terminal of the fuse block. How many brown wires do you have at the starter terminal? Bud
Bud Krueger

Bud, Thanks for your reply. I have two brown wires at the starter terminal. I guess that one of them,the thinner one,runs to the ammeter and the other one is the other end of the wire running to the regulator. The wiring diagram I have for the 9 post regulator does not show a brown wire at the regulator.
Lionel
L.F. Thorne

Lionel, it would seem as if that second brown wire (whichever that one is) is extraneous. If you a WSM you should look at the 9-post wiring diagram on page N.21 and compare it with the 5-post on N.22. The brown wire that does not go to the ammeter for the 5-post goes to the A1 terminal to power the horns at A2. In the 9-post case the horn power (A2) is provided by the brown/white wire coming through the ammeter. It looks as if the wire to the ammeter should be the heavier of the two.
You might want to go to my website and look at Dave Runnings' wiring diagrams, http://www.ttalk.info/TDWiringDiagrams.htm . Bud
Bud Krueger

Bud is correct, You can just stub off the extraneous brown wire at either end. Check first that the rest of the harness is correct for a car with the earlier 9 post regulator. Cheers - Dave
David DuBois

Bud and Dave, Thank you for your advices. I will leave the "spare" brown wire disconnected at both ends. Thanks again.
Lionel.
L.F. Thorne

Bud and Dave, Just a thought. Presumably, if I didn't wire in an ammeter I could fix that extra brown wire to post A of the regulator in place of the feed which comes from the battery via the ammeter.
Lionel.
L.F. Thorne

Sorry, Lionel, I won't touch that. I'd want to know where every wire of your harness is connected. Why don't you want to have a functioning ammeter? Bud
Bud Krueger

Hi Bud, Thanks for your concern! I do intend to wire in the ammeter. I was just thinking out loud and tying to understand how the regulator works. Post A seems to be a constant live feed.

Lionel.
L.F. Thorne

If you are still having trouble send me call me on 01794 388538.
There were several differnt looms for the TD.
R J Marshall

This thread was discussed between 24/02/2014 and 26/02/2014

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