What’s this Box???
 

I need help. Trying to sort out the wiring on a 1930 Model A . The previous owner has a bunch of wires going to a box on the firewall which looks kind of like a voltage regulator. Any help deciphering this would be great. I’m not sure it’s working properly. I am getting bad voltage drain from somewhere.

Thanks

Re: What’s this Box???
 

Hope this helps

Re: What’s this Box???
 

Your 'box' in question is the 'terminal box', in Whirnot's diagram. Left-right doesn't matter so much as getting all of the wires aligned on the appropriate side......

Re: What’s this Box???
 

A picture would be great.

Charlie Stephens

Re: What’s this Box???
 

If the 'box' you're talking about is in the middle top of the firewall and made of black bakelite with 2 thumb screws, then its the terminal box and is supposed to be there.

As mentioned, a picture would help.

Stick a volt meter or test light between battery terminal and battery post to see if there is a draw. If the light lights just keep disconnecting stuff until the light goes out, thats your draw. One place to check is the brake lights, the switch is kinda famous for sticking.

Re: What’s this Box???
 

Here is the box that is being discussed.

Charlie Stephens

Re: What’s this Box???
 

Disconnect it and see what happens.

Re: What’s this Box???
 

My car had a box on the firewall in that same position and it contained about six fuses for various branches of the wiring system. Pull off the cover and look inside.

Re: What’s this Box???
 

It a fuse box Open it up.

Re: What’s this Box???
 

I don’t think it’s the terminal box, as that is located in a more central location on the firewall. This is located on driver side.

Re: What’s this Box???
 

Pandora's box?

Re: What’s this Box???
 

Some sort of an add on aftermarket unit. It's likely a distribution panel for accessories but it's hard to say without seeing inside and knowing where the added wires go.

Re: What’s this Box???
 

Looks like there is a fuse missing right at the top of the box.

Definitely an aftermarket add-on.

Re: What’s this Box???
 

That is a dual circuit head light relay. It helped to get full voltage to the headlights.


Not too uncommon in the old days.


You do not need it if everything is in good condition.


Chris W.

Re: What’s this Box???
 

Best get rid of it and repair the reason it was added in the first place. At least untangle the snarl around the moving control pawls and bundle the wires securely out of the way.

Re: What’s this Box???
 

Worth noting is that it looks like the wire used with the relay was a smaller gauge for 12 volt circuits. Using a heavier gauge that is correct for 6 volts will allow more amps to be carried and with more amperes, it will give brighter headlights.

Re: What’s this Box???
 

If you have the skills or can find help at the closest Model 'A' club, then return things to stock. The drawings, parts and wiring harness are available from all of the Model 'A' suppliers...Ernie in Arizona

Re: What’s this Box???
 

I agree with Ernie, and the wiring isn't too expensive.
Don't eat out a few times, and it's paid for.

Re: What’s this Box???
 

Need to start tracing wires and getting a voltmeter on them with lights on and off and horn blowing and such! It appears a relay switch was put in place due to some other problem of just someone with nothing better to do. I prefer original wiring and making it work rather than adding relays that can fail. (and based on it's appearance, trying to find a replacement!)

Re: What’s this Box???
 

That system reminds me of the south end of a north bound horse! Poor Horse! Ernie in Arizona