Help Understanding Electrical Schematic
 

I am trying to makes sense of an electrical schematic regarding my 1973.5T fuel pump circuit since I am having major issues right now. I downloaded the electrical schematic for my 1973.5T from Pelican (use schematic two and legend two) and where the fuel pump circuit (#8) comes off the fuse box (#7) and down to the connector (#87). Where I get confused is the other wire (brown), which I assume connects to a ground and terminal connector box, but suddenly takes off to other switches or units. There I am confused! :confused:

Can someone who knows these symbols, wire trails and connections, please provide a simple explanation as to what is happening as the brown lead leaves the fuel pump?

My fuel pump seems to work intermittently and it could be something in the circuit.

Thanks

Bob
1973.5T/CIS

The brown ground wire from the fuel pump connector terminates in a chassis ground screw somewhere around the engine compartment electrical panel (can't remember exactly where.) The chassis ground is shared with wires from the rear window defogger and the license plate lights and there are (I think) four separate ground wires on one screw. If you can trace any of the other component grounds to the screw, you should find the ground for the fuel pump as well.

it sounds like it has a common ground with other things. i.e., several ground wires terminate at a single point attached to metal on the chassis with a bolt or screw. if you look in the trunk you can see examples of this.

The shot below is where I unwrapped the harness sorting wires in my 73. It was originally MFI, but that shouldn't matter for the body ground (89) in the schematics you referenced. The fuel pump connector (brown and red/green wires) is shown. If you look carefully you can trace the ground back to the body connector (89) in the top of the photo.

http://forums.pelicanparts.com/uploa...1327271923.jpg
http://forums.pelicanparts.com/uploa...1327271881.jpg

Clarkd,
You seem to be missing the flat braided ground strap to the electrical panel.

Thanks Ed,

The panel ground strap was routed to the engine lid hinge by a PO. I knew that wasn't the original configuration, but I wasn't sure where it should connect.

Clark