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Triumph TR6 - Car won't stop running

I have a 72 tr6 that I just finished putting back together. Everything seems to work except for the car won't stop running when the ignition is turned off. It seems to be kept on by the green wires going to the fuse box, Once I disconnect those and turn the ignition off it will stop running. I recently put the dash back on, is there a wire that I messed up on??

Adam Wilhite

I hope you put the steering wheel on the correct side...just kiddin.

Man u got a good one. Not sure what green wires you are talking about as I do not see a green wire colour that is associated with the ignition.

Me thinks you stumped me!
'72 so ignition is on the column not the dash( I would have had the answer in 2 seconds if it was on the dash).
The only colours of wires going to ignition are:
White (3 wires),White/red (1 wire), and Brown/white (2wires). Also another wire for radio (White/brown??).These should match up with same colour on the ignition switch wiring through connectors. The only Green wire under the dash that would come close to the ignition switch is from the heater. If you have a green wire going to the heater switch and it works that can not be it. Since u just put everything back together it could be out at the fuse box. Do you have schematics for the wiring? What fuse position are the green wires on and what is the colour of wires on the other side of the fuse? Green supplies power to:wiper motor, back up lights, engine temp guage, fuel guage and sender, heater switch,and turn signal flasher unit.
Adam, a little more info please
Rick C

Rick Crawford

Ok, there are no green wires going to the ignition. The white wires (from the ignition and from the coil) go the the fuse box. On the other end is the green wires. When the ignition is turned on it is supposed to allow the green wires to operate. IE the wipers.etc..... The problem is when the ignition is off, the power from the ignition side (white wires) are turned off, but are some how getting power from teh green wires. I have tested this by disconnecting the green wire (at the fuse box) when the ignitionis turned off. The car cuts off. With the ignition on, the car doesn't cut off when the green wires are disconnected. Therefore I am fairy sure that somewhere in the green wire set, something is getting power to it non stop, which opens the circuit to the white wires in the fuse box which keeps the car running. This where I have stopped my diagnosis. So basically the green wires are getting power to them when they shouldn't?????

Little confused, Appreciate the help.
Adam Wilhite

First off must have been sitting on the enter key right side of keyboard ( I am teaching her how to type).

OK the fuse box wiring is other colour wires to these 2 terminals correct??
You are correct in that the green wires supply power to what I said WAY up above. There are two things in that circuit that DOES have constant voltage to it.

#1: the hazard flasher unit. It is a purple wire from fuse box(next fuse down) 3 purple wires one side, one brown the other side to starter motor to the + battery. If I am not mistaken, your flasher unit is just infront of the fuse box. Unplug it and see if problem goes away.

#2:This one is a long shot... the seat belt warning gearbox switch. I do not have this set up at all so only going by what I see in '72-'74 schematics. One side of this switch (Green wire.. do not even know where it is located) is directly ( sorta..through connectors and common connections) connected to the green wires at the fuse box. Also this side of switch supplies power to reverse lamp switch (green wire) and the 2 bulbs. The other side of this seat belt warning switch is a bullet connector with what appears to be green/light green wire which goes to drivers belt switch,passengers seat and belt switch through a diode to left hand door switch.....more stuff...finally purple constant live side of fuse box. If you know where this seat belt warning gear box switch is..disconnect it and see if problem goes away. As said this is a long shot at the problem.

So if disconnecting the hazzard flasher unit solves problem then we will look at how it gets wired up.
Hope this does it for u.
Adam, do you have schematics??
Rick C
Rick Crawford

Got the schematics, I've already tried to disconnectthe hazard flasher. Same problem. I'll check the seat belt warning lamp items. I do not think the seat belt warning stuff is even hooked up??? I'll take a quick look after i get home from work, I appreciate the help.

Adam Wilhite

I bow to Rick's superior knowledge of electrics, a black art to me, but have you considered the usual causes of the "dieselling" or "running-on", that plagues Triumph engines?

The usual causes are a weak mixture, ignition too advanced, or overheating due to poor cooling. The last I doubt if you have just rebuilt the engine. The first two are all too likely, but not too difficult to cure. Use the highest octane fuel you can find, or add some octane booster, at least until you have the engine running reliably, and then experiment.

You may find other suggestions for curing 'running-on', here or on other BBs, if you do searches.


Good thought but I doubt run-on is his problem as Adam has said, he dsconnects some wires and the engine will shut down.
Adam, as said #2 is a long shot. Maybe it is time we do some voltage readings. Specifically, disconnect the white wires at the fuse and take a voltage reading at the green wire side. Is there 12V (or close to it)? If so then yes Houston, we have a problem. Another thought: if you disconnect the double green wire to the stop light switch then you take a few items out of the you have 12 volts at this spade terminal? Unfortunataelyball these green wires are up under the dash and it is a case to determine if one of them is sitting on a constant power connection.
The seat sensor switch might be at a connection somewhere behind your driver seat under the carpet.

A thought: If all of the items at the green wires receive power with ignition on then they should only work with ignition on. Do any of them work with the ignition off??

You it page # 86.00.08?

I would imagine that if you pulled the fuse out you would be able to start and stop the engine but would loose all the green wire items. Try this. For sure it would tell if you have constant power on the green side of the fuse. Well did this same thing with a votage reading as above. But this would say if the ignition is working and not wired incorrectly.
Let me know...this is getting interesting!
Rick C
Rick Crawford

I have one word to myself...DUH!
"A thought: If all of the items at the green wires receive power with ignition on then they should only work with ignition on. Do any of them work with the ignition off??"

Ofcourse you will have all of the items working with ignition off...that appears to be your problem....constant power that side of the fuse and this is a common connection poit.. If u look at the schematic there is a major connection point ( from the stop lamp switch)which ties together: [wiper switch (36), windshield washer and squirter(38+39), Volt. stabilizer(40) and temp indicator and transmitter (38+39)and fuel indicator and sender (43+44), seat belt warning gearbox switch (66),heater switch and the motor (45+46),and finally hazard switch (56). This major connection point for sure will be burried in the harness. But we can eliminate some of the green wire powered items.

You will have spade connectors (green wire) on one side of: 36,38 (which will also eliminate 39),40
( which will also eliminate 41,42,43,and44),45 (which will also eliminate 46),
My point being with this above info is that "systems" need to eliminated systematicaly till we find the one that when disconnected does not put a voltage back to the green side of the fuse.
Unfortunately, you are working under the dash and you almost need a second person to tell you if the voltage drops when an item is disconnected. Maybe you could extend the wires of your volt meter so that it sits on the passenger seat and you can "just" disconnect the item and watch the meter at the same time.
If this does not find it then......well....we will discuss that later.
Rick C
Rick Crawford

Unfortunately I just had shoulder surgery so I haven't been able to get to the tr since last Monday. Hopefully I can get out there soon, it's gonna be tough, I can't lift my arm over my head for 6 weeks. I appreciate your help and will let you know the outcome when I get back in the garage.

Adam Wilhite

This thread was discussed between 18/11/2002 and 22/11/2002

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