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Ammeter wiring

Ludwig

New Member
Hello,
I am from Belgium and new to this forum.
After many years of standstill I resumed work on a '66 conv.
I have a question about the ammeter wiring.
The PO has done some work on the harness, so it is likely no longer original
The yellow wire in the pic comes from the ammeter, but has nothing to connect to.
I can make the missing wire, no problem, but what does it connect to?
The wiring diagram is not very clear (to me..) so I prefer to ask before blowing something up.
Thanks.

( I'll probably have more questions later)
 

Horseplay

I Don't Care. Do you?
Our resident wiring expert Midlife will chime in here to confirm or correct me but that wire (if really off the amp meter #654) connects to wire #37 which is the black/yellow in the hot post of the starter solenoid off the alternator. It could also just be the pigtail used to test the alternator output.
 

B67FSTB

The NorCal dude from Belgium
Hello neighbour !! Where are you located.
( van welke plaats ben je ? )

Verstuurd vanaf mijn SM-A605FN met Tapatalk
 

Ludwig

New Member
Our resident wiring expert Midlife will chime in here to confirm or correct me but that wire (if really off the amp meter #654) connects to wire #37 which is the black/yellow in the hot post of the starter solenoid off the alternator. It could also just be the pigtail used to test the alternator output.
Thanks Terry.
So I can safely connect it to this wire? :

 

Horseplay

I Don't Care. Do you?
The amp meter should have 2 wires coming off it, one being yellow. If you can verify the wire in your pic is the other end of the wire attached to the meter you can but I'm always nervous about wiring on old cars where others have messed with the harness. If you look a the wiring picture you just posted you will see another open ended wire shown coming off the main firewall connector. That is the yellow wire lead from the amp meter.
I'd hold off making the connection until Mid chimes in. He is our resident expert on all things wiring. let him confirm stuff just to be sure. I'm surprised he hasn't already as it's not like he has anything else to be doing these days!
 

B67FSTB

The NorCal dude from Belgium
3511 Kuringen.

Looks like this yellow lead connects to the B+ terminal of the alternator and thereby is a constant 12v lead. So it , the ammeter, measures the difference in voltage between the output of the alternator and the voltage of the battery. Right?

Verstuurd vanaf mijn SM-A605FN met Tapatalk
 

Midlife

Well-Known Member
Staff member
Moderator
OK, first off, that picture is for an alternator indicator lamp system, so all bets using that schematic are off. How do I know? Ammeter systems use only 3 of the 4 pins at the voltage regulator plug. You need to check this to see if this is the right "headlight" harness.

The 66 engine gauge feed harness has both a yellow wire and a red wire lead (these are the 2 female leads). The red wire goes to the starter solenoid, and the yellow wire mates to a male bullet on either the alternator harness or the headlight harness (I can't remember which). The 65 version of the headlight harness for the linear speedometer is not the right harness; the 66 is unique to that year.

If you can't find the right male bullet with yellow wire near the starter solenoid, then you probably have a 65 headlight harness. Check if all four pins are used at the voltage regulator on the driver's side fender to be sure. You should have only 3 pins used.
 

Ludwig

New Member
Midlife:
you nailed it.
I took out the '66 harness years ago.
When rewiring, I didn't like the look of it , like paint spray on the lamp sockets and horn wires ( I hate that..) so I replaced it with a better looking harness that I had lying around.
But like I learned now, a '65 harness.
4 wires connected at the regulator:


Looking at the '66 harness, the 'missing' yellow wire is spliced off the fat black/yellow wire (37):


I think the best way to go is to order a new harness, unless it is easy to modify the '65 harness.
I don't see much difference between the 2.
What do you think?
 
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