MAD ammeter bypass question
Most of the 60's and first few years of the 70s the A body fusebox has a fusebox like this. Both the constant hot (Q1)and switched Accessory (Q2) feeds connect to busses with an extra terminal.
Top view of a standard '67 fusebox with cover off.
That second terminal on the switched accessory buss was used by the factory to add a fuse for optional accessories such as tachometer and/or air conditioner (yes I know very different loads, but thats what was done). Here's an example that a member here was working on.
As I mentioned in an earlier post, the most common heavy duty factory wiring we see on the FABO is on cars with rear window defrost grids.* Those use ring terminals on the ammeter stud as a junction. I do not recall if anyone has posted photos of a fleet optioned A-body, although the wiring diagram shows in some of the service manuals and hookups are shown on a 67-69 assembly drawing.
In any event the fusebox buss is often easier to access.
*Links to examples from 73, 74, and a '75 here
Most of the 60's and first few years of the 70s the A body fusebox has a fusebox like this. Both the constant hot (Q1)and switched Accessory (Q2) feeds connect to busses with an extra terminal.
Top view of a standard '67 fusebox with cover off.
That second terminal on the switched accessory buss was used by the factory to add a fuse for optional accessories such as tachometer and/or air conditioner (yes I know very different loads, but thats what was done). Here's an example that a member here was working on.
As I mentioned in an earlier post, the most common heavy duty factory wiring we see on the FABO is on cars with rear window defrost grids.* Those use ring terminals on the ammeter stud as a junction. I do not recall if anyone has posted photos of a fleet optioned A-body, although the wiring diagram shows in some of the service manuals and hookups are shown on a 67-69 assembly drawing.
In any event the fusebox buss is often easier to access.
*Links to examples from 73, 74, and a '75 here