When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Good evening,
My new to me ‘62 ammeter seems to have been deliberately left unwired. What is the function of the black wire that goes to the solenoid from the ammeter?
I have the wiring diagrams book and the corrected ammeter page. Near this ammeter, but hanging in the breeze, is a machine screw joining red wires and a black wire that goes into a wrapped bundle. Right now, everything else is working. I tested continuity thru the ammeter and it responded to a AAA battery, so I guess it can work.
But, before chasing all this down, how much current flows through the ammeter? I know and understand it is not truly measuring current from reading other threads. To prevent this live 12V shock hazard, I would like to at least use the ammeter post to bind all this safely. I will work to test continuity of the black wire to see if it goes to the solenoid. But I am trying to guess why this would have been done on what otherwise looks like a good restoration. If the black wire does go to the solenoid, what would I have to lose connecting the ammeter? If it does not go to the solenoid, would current flow through the meter anyway just as it is tied together on this silly machine screw?
Thank you.
Generally that means the ammeter shunt has burned out due to an overload which instantly fries the ammeter and renders the car dead. The 'correct' workaround is to move all the wires to one post of the ammeter (it doesn't matter which one). That completes the circuit but renders the ammeter useless. If it responded to a AAA battery, it may be ok but that begs the question of why is was bypassed. The black wire is the main feed from the battery and is on one side of the meter and the other wires are connected to the other post. If you get them backwards there is no harm but the meter reads backwards so reverse them.
On a 62 and prior the battery gauge IS an ammeter and all the current passes through it. The black wire is connected directly to the battery black wire on the starter solenoid lug. It is not a low current situation, those wires have direct connection to the battery and are not fused. That's why many, including myself, added a fuse in line with the black wire leaving the solenoid black wire and going up to the gauge. It feeds the lighter and everything else in the car. The threads you read about shunting are for 63 and up. I hope that connection you have is VERY well insulated and isolated.
I have no idea why it was bypassed unless it was defective and not allowing current to pass through.
Thank you for the info about the direct connection. I was confused from the wiring diagram versus posts of potentials dealing with later cars.
And no, this connection is an exposed hazard- were the steering wheel smaller, an exposed right knee would get tattooed.
Generally that means the ammeter shunt has burned out due to an overload which instantly fries the ammeter and renders the car dead. The 'correct' workaround is to move all the wires to one post of the ammeter (it doesn't matter which one). That completes the circuit but renders the ammeter useless. If it responded to a AAA battery, it may be ok but that begs the question of why is was bypassed. The black wire is the main feed from the battery and is on one side of the meter and the other wires are connected to the other post. If you get them backwards there is no harm but the meter reads backwards so reverse them.
Originally Posted by Axe Maddock
Thank you for the info about the direct connection. I was confused from the wiring diagram versus posts of potentials dealing with later cars.
And no, this connection is an exposed hazard- were the steering wheel smaller, an exposed right knee would get tattooed.
There is something of a balancing act about fusing the main power feed. On the one hand, you don't want a fire but on the other consider the case of the fuse blowing just as you are crossing a railroad track. GM turned to fusible links a little later and their advantage over a typical fuse is that they react slower which is a good thing in this context. My answer to this issue on my '54 which is wired far worse from the factory than your car was to add an auto-reset circuit breaker just after the main power feed at the starter. I also was careful to not cut or splice the harness or drill any new holes anywhere so that I can return to "as-built" status if needed.
There is something of a balancing act about fusing the main power feed. On the one hand, you don't want a fire but on the other consider the case of the fuse blowing just as you are crossing a railroad track. GM turned to fusible links a little later and their advantage over a typical fuse is that they react slower which is a good thing in this context. My answer to this issue on my '54 which is wired far worse from the factory than your car was to add an auto-reset circuit breaker just after the main power feed at the starter. I also was careful to not cut or splice the harness or drill any new holes anywhere so that I can return to "as-built" status if needed.
Roger that. Plenty of RRXing here.
As I embark upon this project, quick C1 question- should turn signals function with the ignition in “Lock?” I can select L and R signals with the ignition off. It makes sense given this hot lead from the solenoid. I am wandering around the wiring diagram and cannot quite see what effect the switch has on turn signals.
Thank you.
The turn signals should only function in the RUN position. Your flasher appears to be fed from an unswitched source. You'll find that most diagrams treat switches as pretty much black boxes so you have little knowledge of their internal connections unless you ohm every terminal out. Be glad you are not working on a 53-55 6 volt car because there the left turn signal indicator is connected to the RIGHT front turn signal lamp and vice versa and that is actually correct! You should probably look at your harness carefully and decide if a new harness might be your least evil option because it sounds as though yours has been 'improved'. One word of caution: Even with a brand new harness C1 wiring is still dangerous by modern standards so you might still consider circuit protection especially with respect to the main power feed.
The turn signal flasher should be powered by the pink wire of the ignition switch. Possibly someone wired it to the always hot circuit that feeds the lighter and brake lights. The brake light should work with the key off, but not the turn signals.
Ammeter omitted, why?
