The four wires (black, gray, purple, black w/white stripe) connected to the fuel pump of my 1997 GMC Jimmy have no electric current. I tested the wires above the connection of the harness. Still no electric.

ASK MASTERPRO, THIS .
ONLY THEY KNOW WHAT THEY DID.

Factory side wires:
Orange is constant 12 volts
yellow is switched 12 volts
Black Ground
Gray Illumination
Brown Dimmer
Tan LF +
Gray LF-
Lt Grn RF+
Drk Grn RF-
Brown LR+
Yellow LR-
Lt Blue RR+
Drk Blue RR-
The aftermarket reverse harness should be mrked I hope that helps

Should be four ! 1 gray B+ power supply , 2 PPL - purple fuel level signal wire to the PCM - engine computer , 3 Black - ground for fuel pump motor . 4 Black with white trace - ground for fuel level sensor !

Make sure the ground is good, that truck was known for a bad connector near the Trannie cross member. Find your plug at fuel pump,4 wires..2 black, gray and purple. Black and purple are for the float. Gray is power to pump, black with yellow is ground for pump. When key is turned grey wire gets power check good ground . If power and grounds are good replace pump if not fix ground or replace relay

The gray wire goes from the pump relay to the pump. The black white wire is the ground for the pump. The purple is for the gauge on the dash and the black is ground for the sending unit. I don't list a white wire being used.
If the colors on the truck don't match the tank, you'll have to test them to verify each circuit.

match up all others then the last one should be right

go to auto part store get digram

The fuel pump relay should have a schematic on it so you can check it with an ohm meter for a short. If it checks ok and when you turn the key on, you do not hear the pump then replace the pump

if its the correct harness then yes... i would follow colors.conecting the thinner black to the orange/black.

i have built and repaired wire harness' for four winds rv for 5 yrs now and previously gm cars for 4 yrs

Go to autozones web sight and look up under self repair. they have a wire diagram.