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roofman

Jedi Knight
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You may remember I had the car ( 1972 TR6) that would not shut off, so I bought a new ignition switch from Moss a Lucas 157 SA. Now the fun begins.
The new lucas switch has 5 spots to hook up wires, 3 single post ( marked #1,2,5) and 1 double post( marked #3).

My old switch is a non-lucas brand.It has 5 hookups also.
There is a red/white wire-
A double white wire with a blue wire tied in( blue wire not hooked up to anything, radio? )
A white wire-
And a brown white wire that is split so 2 brown white wires come out of the split and BOTH hook to different locations on the switch.

The bently manual on page 561 shows white, brown white, red white, and aux. with no color given.

Dan Masters site shows 3 white, 1 red white, and 2 brown white wires.

Ok so what kind of mess do I have, and which wires go where on the new lucas switch? /ubbthreads/images/graemlins/crazyeyes.gif
 
70 looks but no help yet. Anyone have a clue?
 
Well, I'm puzzled. Mostly about "5 spots to hook up wires"! By any chance, are two of those "spots" on the same post, and/or are the posts numbered? In my factory manual, I see only 4- or 6-post ignition switches!? /ubbthreads/images/graemlins/confused.gif
 
On the new lucas switch, #3 is a double, and the others are single wire hookups and are numbered 1,2,5 there is no #4 it would be the 2nd of the doubled post #3.
I am also confused by the Bentley manual as it shows the wire colors but no reference to which # post they go to. And I seem to have too many wires!
 
Does this help you? Please see attached pdf file for ignition wiring diagraham.
 
I have that same diagram in the Bentley manual. Does any one know which wire goes to each # terminal on the back of the switch? And does that split brown and white wire sound correct? Thanks for the help so far.
 
I had a similar issue recently - I just ran down to the garage and mine is wired per the diagram that Paul attached.

Should be pretty easy to tell if the radio is the blue wire. If you hook it to the aux it should only come on when he ignition switch is all the way turned (before the starter circuit fires).
 
More info;


My switch - also new from Moss - has #1, #2, #3, and #5.

#1 - open

#2 - two connections, white/brown and white/brown

#3 - red/white

#5 - two connections, single white and a double white/white.

I'd get someone to confirm this is correct before you haul off and do anything irreversible. <grin>
 
So if I read this correctly:
Terminal 1 - nothing hooked up
Terminal 2 - 2 brown and white wires
terminal 3 - red white wire/ second attached terminal
nothing hooked up
terminal 5 - 3 white wires tied together

Which terminal would a radio hookup go to?
You say 2 connections at terminal 5, what do you mean?
Thanks
 
He means there are dual "spades" for the one terminal (both #2 & #5).

Brown, brown/white should be 12V power source (you can confirm this with a VOM or a 12V test light), white to deliver voltage to the fuse block/coil when iggy is on, white/red is the starter solenoid lead, blue was headlights but they weren't switched so likely it's a "rogue" for the radio.
 
Currently, I have 1 white wire to the second terminal at #3 which is a dual terminal, and a second white brown on #1 (for some reason there is a spliter on my white/ brown so there is 2 white/ browns) It appears I should not have that splitter and the white/brown on terminal one must be wrong.
The blue odd wire is on #5 with the dual white wire.

Is #5 where the radio should go? or is 2-5 the same and it can go on either one?
 
Hope to put this back together today, any idea which terminal would have a radio lead?
 
Well put it all together, started it upand now....
1. starter stays engaged
2. turn signals don't work
3. Gas guage not registering
but it shut off with the key thank goodness.
biggest concern is starter staying engaged. I know for a fact the red/white wire is on terminal 3
any ideas?
The starter ran for a minute or two while I tried to "figure out that noise" and my new Optima battery ran dead. Could the starter running drain a battery in 1-2 minutes?
 
I honestly don't know which terminal on your switch should get what wire. Sorry, but with that many things going wrong at once I would definitely invest in checking out each terminal on the switch and each wire you think attaches to it with a continuity trace. Once you are certain of the path then you can check DC voltage from each wire prior to connection to switch. You can gat a fairly inexpensive and accurate digital mutimeter from Sears. $9.99 last I looked. Tracing wires is never my idea of fun but sometimes this is what you have to do to find the fault once and for all.
 
One positive is that a marker light that stopped working is working now? Go figure.
 
Are your grounds in OK shape / well connected?

Isn't the starter current controlled by the combination switch? I wouldn't think that the wiring would cause that to run on...?
 
tdskip said:
Are your grounds in OK shape / well connected?

Isn't the starter current controlled by the combination switch? I wouldn't think that the wiring would cause that to run on...?

If the starter circuit got somehow hooked into the run circuit, then the starter would continue to run.

Yes it is possible to drain a battery in 1-2 minutes of cranking. I'd be surprised if it DIDN"T drain in that period of time.

As stated above by Harry , you are going to have to ohm out the switch terminals and hook up the appropriate wires according to the wiring diagrams as to where they go.
 
Now that the battery is charged... I tried to start the car and bingo started right up, but the key must be manually turned back one notch to kill the starter, It doen't want to automatically default to the run position. Does this sound like a defective ignition switch, or wiring?
 
If you have to turn the key away from the start position then you have a bad switch, it should spring back when you release the key. Wayne
 
Hold on a second! My new Moss switch does the EXACT same thing. I thought it was normal.

I have to manual click back on notch or the starter stays in engaged.

Sounds like we're either both screwed up or that is simply how the new Moss switch behaves...
 
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