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TR2/3/3A 1962 TR3B wiring

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pace

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I had the front clip off and had marked the wiring and even took pics. The markings were erased and the pic are not clear enough. I have matched all wires coming from the headlights, turn signals, horn, etc. but I have one lite green wire left over on the left side coming from the turn signals and of course, they do not work. All other lights work however, from the guage in the car, the generator is over charging. Can anyone tell me what the light green wire hooks up to and why would the generator be overcharging. How do you check the voltage regulator?

A color pic of the wiring would be appreciated.

Mike
 
A green wire is fused power that comes on with the ignition switch. On most '3 wiring harness there is a complex arrangement that allows the same harness to be used for both RHD & LHD -- leaving one female bullet connector empty depending on which side the steering box is on.

You may have a hold of the green wire that ultimately sends power up the steering column to the trafficator... the other end of that wire goes to (if I remember right) a 4-place female bullet connector on top of the left wing.

Other than that I do not recall any green wire in the neighborhood -- are you sure it doesn't have a stripe? I know of no use of Light Green wire (code 66) on a TR3.

Here is a TR3A/B wiring diagram in case you need it:

https://www.advanceautowire.com/tr24a.pdf
 
[ QUOTE ]
...How do you check the voltage regulator?

[/ QUOTE ]

Mike here is a basic step-thru charging system check:

Some basic charging system tests (note that if your car is positive
ground, all the voltages are negative) :

Engine off :
1) Double check the mechanical stuff : fan belt present and snug,
generator snug on mounts, wires firmly connected to generator, etc. You
should only be able to turn the generator fan with great difficulty, if
at all. If the generator has been off the car, it's worth repolarizing
it.

2) remove the wire from the 'F' terminal on the control box
(regulator). Measure the resistance between the F and D terminals, it
should be under 1 ohm. If not, the control box is bad.

3) Measure the resistance between the wire that came off the F terminal
and ground. It should be between 5 and 10 ohms. If not, either the
generator or (more likely) the wiring is bad.

Put the wires back, Start the engine, and set it for a fast idle
(1500-2000 rpm)

4) Terminal E to battery ground post should be under 1.0 volts. If not,
you have a bad ground. Also check from E to the generator housing.

5) Measure D to E. This should be around 13-15v, if it is then the
generator is working. Higher indicates a bad regulator.

6) Assuming D-E is under 13v, compare it with A-E. If they are the
same, the ignition lamp should be out. If not, the wiring to the lamp
is wrong.

7) Also assuming D-E is under 13v, check D-F. It should be under 1.0v,
if not, the regulator is bad or badly misadjusted. One exception to
this is if the ammeter is reading a lot of charge at this point, 15 amps
or more, which could indicate a bad or deeply discharged battery.

8) As a final check, (again assuming step 5 was under 13v) stop the
engine, remove both wires from the generator, jumper the terminals
together and connect the voltmeter from either terminal to ground.
Start the engine. Rev no higher than about 750 rpm, and check the
voltmeter reading. If you don't get at least 15v, the generator is
definitely bad. According to the book, around 4-8v indicates a bad
armature or brushes, around 1v indicates a bad field. If you do get
15v, reconnect the wires and repeat the test with the F and D wires at
the regulator. If you get different results here, then the wires are
bad.
 
[ QUOTE ]
...I know of no use of Light Green wire (code 66) on a TR3...

[/ QUOTE ]

Even as I said that I had the nagging feeling I was forgetting something. There IS a Light Green wire -- it connects the turn signal flasher to the turn signal indicator light.

Not sure if that could be the wire you describe but if unconnected it sure as shootin' would not let the turn signals work.
 
George, that is the light green wire I am talking about, I can't find where it should plug in on the left side. I really appreciate your help. Wiring is my weak suit and gets me aggrevated everytime I have to fool with it. Thanks again.

Mike
 
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