Wiring harness issue? Maybe?

[moozieman]

So ive been having trouble getting my fuel pump to work when plugged into the wiring harness. So i had to hardwire it straight to the battery with a switch in between. It wasnt a huge priority to fix but i've realized that my fuel gauge doesnt work either so im thinking theres a problem with the back end of the harness. I tested the connectors for the fuel pump that are under the passenger seat and was reading less than half a volt while the car was running. Any suggestions?

[SteveJ]

I suggest that you add the year of your car.

[moozieman]

On 8/30/2019 at 9:10 PM, SteveJ said:

I suggest that you add the year of your car.

1977

[hls30.com]

The harness passes through the floor in the passenger side under/behind the seat...maybe worn and grounding at the pass through?

 

Edited September 5, 2019 by hls30.com

[EuroDat]

If the engine is running and you are readin 0.5volts, something wrong with the way you are testing it or your meter is bad.

What is the fuel gauge doing. Reading full is a sign of a bad ground which could be related to the pump problem, but not likely. If it's reading empty, then you have most likely a problem with the power supply to your gauge.

Sounds like you have two separate problems

[Jeff Berk]

Do you have a wiring harness diagram

http://www.atlanticz.ca/zclub/techtips/wiringdiagrams/

You likely need to start at where you had the low voltage and work your way back to the next point to see what the voltage is. Be prepared for a slow tedious few hours.