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MG TD TF 1500 - I need how to instruction on TD operation

I hauled this old gal down from Maryland a couple weeks ago. got all the mouse nests and squirrel stuff cleaned out. I'm trying to figure out what does what on the dash. I hook up a battery charger and even with the key verticle and the switch straight up I still get a red light on the lower left of dash. Not sure what that is. The fuel pump seems to be live at all times as well. No matter how I turn the key and no matter what position the switch is in. I can turn the switch 2 clicks to the right and the headlights come on.

I guess I just don't know what the dash lights, knobs, switches etc. do and sure can't figure out how the ignition switch works. Hard to believe anything should be live with the switches off. I have a TD resto manual on the way. My uncle indicated that things should be good, but unfortunately he passed away before I got the car so I don't have him to ask questions of. If you can point me to some reference material on the net that would be helpful.

BTW, I do know this should be a positive ground system so I made sure to hook it up as such.
l rutt

My guess is that the ignition switch is in need of rebuilding. That would be my conclusion after I checked the back side of the igniton switch to make sure the squirrels or mice had not shorted the main ignition wires somehow.
Jim Merz

Generally speaking, you've come to the right place. Sit back and be prepared for a flood of good advice.

Dick Thomas
Dick Thomas

First of all the ignition switch and the headlight switch share the same housing.
Sounds like you have a bad ignition switch or the wires are crossed/bridged behind it. The lights (big black switch) are live even without the key on... and your right it is 'one click' parking lights, 'two clicks' headlights.
If the red light is the far left one, that is the ignition warning light and should go out when you start the engine and rev a bit... beside that is a green one which is the low fuel warning light, in the middle you may have a third one which would be the turn signals if so equipped!
Does your starter turn over when you pull the starter button (choke looks the same and is to the right of the starter?)
gblawson (gordon)- TD#27667

right now I have not put a battery on it as I was fearful of a meltdown so just stuck with a battery charger, amp limited. So the big black lever just controls the lights, I see. The key switch in the middle then is supposed to control engine functions. Odd that the fuel pump is live in both positions, and that the red light is also on in both positions. I know for a fact the wires to the fuel tank are not connected yet I don't geta green light so something amiss there. Looks like I may have a problem with the key switch then. I'll delve into that. I noticed there is a hi-lo light switch down by the clutch pedal, haven't tried that yet. Horn switch was and still doesn't seem to work. I took it apart and cleaned but still no worky. Something else must be wrong. I remember reading about the turn sig switch refurb in a tech talk article. Mine seems dry and will need some attention. I also plan to actually pull the genny and starter before use to make sure brushes move freely and the armatures are nice. No need to burn things up right away.

I tell you, that under dash panel was a PITA. It was in bad shape anyhow so I had to bugger it up some to get it out. How the heck would a person get one back in though. It's all one piece??? Since this car doesn't have original engine nor hardly any of the MKII goodies I'm not going to be so worried about a perfect resto. I think I have an idea for a better under dash solution that will be easier to deal with. Will definately need a new glove box enclosure though.
l rutt


If the car entered the world as a legitimate Mark II, then with a few exceptions, most parts are still available to make it back into a Mark II.

The only two exceptions I can think of is a) The air cleaner/oil bath ass'y and b) the rear bumper Mark II flash and these are neigh impossible to find.

The trick stuff like Andrex shocks are still available but terribly dear, and of course mounting a second fuel pump, a TF head and 1½" SU's are all do-able.

But I like your approach. Let's get the baby on the road, and worry about the rest of the stuff later.

Gord Clark
Rockburn, Qué.
Gordon A. Clark

Oddly enough I have the hood badging, bumper badging, and control arm andrex shock brackets. I know I could spend a lot of extra money and make ita MKII again but to be honest, I just want a real nice driver. Not a show winner. That is what I've done with all my classic bikes. I keep them as original as possible but just want to make sure I don't have to worry about taking them out and using them. I think my only departure on this car will be changing over from the green interior to a tan or biscuit interior. Tan just looks soo good with the BRG paint.

but first sort out the mechanicals.
l rutt

l rutt, first thing to do is to obtain an owner's manual. It will tell you about the various switches, etc. It is bad practice to connect a battery charger into an auto without a battery. The unfiltered output of some chargers can damage some circuits. The battery doesn't have to be a good one. Where did you connect the charger? If the fuel pump is powered -- the ignition circuit probably is too. Be careful.
Bud Krueger

Great advice from Bud. I would also purchase the NEMGTRegister's "The Sacred Octagon" magaine on CD. It contains all issues up until 2006 or so, and will answer many questions. Also buy the "T-series Handbook " (not sure if that is exactly the right name- mine is at home) from them. It has all of the tech articles from the TSO, with great and simple explanations of carbs, electrics, etc. I think there are dash pictures in there also. George
George Butz

I Rutt -- If the wires to the fuel tank are not connected the green fuel warning light will not light because the sensor in the tank provides a ground for the light. When there is plenty of fuel the tank sensor is open circuit, when the wires are not connected it is also open circuit. You could ground the wire and see if the light comes on.

With the things you are reporting I would crawl under the dash and check the wires to the ignition switch. Sounds like the PO moved some wires to where they are not supposed to be. Or as has been suggested the switch itself may be fouled up.

Can you read the color codes on the wires under the dash?The sun never got to those wires so they may be quite readable. I(along with many others) have a wiring diagram with the colors depicted. The source was the TSO a few issues ago. If that is something you would like to get for yourself I'll look up the issue and the address of the guy who has the back issues.


R. K. (Bob) Jeffers

I Rutt,

I'm colorblind, but I've never been under an unrestored dash in a TD that had discernable colors! LOL. But with the factory wiring diagram, it is a straight forward process to veryify a few things. Bud is correct about hooking a battery charger to your circuits, a battery makes a very nice dampener to avoid problems.

If you have a 'windowless' ignition switch, you will want to have that switch restored if it is defective. But one thing you could do is disconnect the wires from the back of the switch and with a multi-meter check for continuity between the various switch points. Terminal A with the brown with blue wire is your main power into the switch. Terminal IG is the power out (I can see the guys with real electrical knowledge rolling their eyes with my terminology!) The IG has White wires going to the Ignition coil and fuel pump (both via the A3 fuse terminal, and then via the A3 terminal on the fuse block to to the A4 fused side to power the green wire circuits (wiper motor, petrol light, Turn Signals, stop lamps. The IG terminal also feeds one side of the ignition warning light (the red one).

The side switch for the lights gets its power from the A terminal, so running lights and headlamps should work with the ignition off. Terminal H is for the headlights (the blue circuit) and terminal T is for the other lights (the red circuit). T has the impossibility of having four wires going to it, I routinely substitute a heavier wire at the switch, and then use double bullet connectors to feed the others into the circuit.

A friend and I recently rewired his Mk II using a new loom from British Wiring. It took care of all the problems. It is a pretty good fix if your loom is shot, and is relatively easy to install in a finished car. (no relationship to

Well, good luck and have fun!

Dave Braun

Here's a thought, it is actually possible to put one of the two fuses in between the fuse clips instead of in the proper place. If someone were to do this, strange things happen. Don't ask how I know, I must have read about it somewhere. Yeah, that's it, I read about it. ;)

Bob Farnam

Bob has it right. Strange things happen when you do that, and I believe one is that the generator light stays on all the time. How do I know? Er, uhm, eh, I think I "may have" read about it like Bob :-)


Larry Karpman

Stuffing one of the fuses between the two fuse holders on a late model TD with the five post regulator and a separate fuse block will indeed turn everything on just like you had switched the ignition on (the scary part about that is someone who knows T series MGs can make that switch with the fuse and drive off with your car). I would suggest checking that situation out before crawling under the dash.

There is nothing in a TDs electrical system that will be damaged by unfiltered voltage from a battery charger unless possibly one has Bob Jeffers' solid state regulator installed and I doubt that even that would be affected. All the same, if you are worried about the possibility of damage, just hook up the battery with a 10 amp fuse in the ground line. That way, any shorts that might fry a harness will instead just blow the fuse. Cheers - Dave
David DuBois

Will get to this.

Been checking other things out. Thanks all.
l rutt

This thread was discussed between 17/04/2008 and 20/04/2008

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