How does a fuel pump relay get power?

The relay wires should have ground on two wires, power on one wire and switched power on another wire. To activate the fuel pump the computer actually connects one of the ground wires to complete the circuit and send power to the fuel pump.

How can I tell if my fuel pump relay is defective?

It’ll also show you how to bench test the fuel pump relay in a step-by-step way to find out if it’s defective or not. Contents of this tutorial: Before You Start Your Fuel Pump Relay Diagnostic. TEST 1: Swapping Out The Fuel Pump Relay. TEST 2: Making Sure The Fuel Pump Relay Has Power. TEST 3: Bypassing The Fuel Pump Relay.

Is there no power to the fuel pump?

No power to the fuel pump and the fuel relay is not getti… Q: No power to the fuel pump and the fuel relay is not getting power. My car has 190000 miles.

How to test a GM 4.3L fuel pump?

More GM 4.3L, 5.0L, and 5.7L Tutorials. It’s very important that you start off your fuel pump relay diagnostic by first testing the fuel pump pressure with a fuel pressure test gauge. If the fuel pump relay IS NOT activating the fuel pump, the fuel pressure test gauge will register 0 PSI when cranking the engine.

Why is the fuel pump and relay not working?

The ignition circuit, which includes the ignition switch, controls power to many components, including the fuel pump and relay. If there is an issue with the switch or the circuit, perhaps a wiring problem, then power to the fuel system may be cut off.

How to test a GMC fuel pump relay?

TEST 1: Swapping Out The Fuel Pump Relay. TEST 2: Making Sure The Fuel Pump Relay Has Power. TEST 3: Bypassing The Fuel Pump Relay. TEST 4: Bench Testing The Fuel Pump Relay. Fuel Pump Circuit Diagram. Where To Buy The Fuel Pump Relay. More GM 4.3L, 5.0L, and 5.7L Tutorials.

Where is the power wire on a Chevy fuel pump?

Want to make sure its a 5.7L engine with the classic style truck and not the new style truck with the 6.0L Right? On the fuel pump connector, the gray wire is the power wire. The thick black wire is the ground.

How can I Fix my Chevy fuel pump?

Ask a Chevy Mechanic for Answers ASAP By continuing to use this site you consent to the use of cookies on your device as described in our cookie policy unless you have disabled them. My Chevy has no power to fuel pump. How can I fix it? no power to fuel pump… Submitted: 10 years ago. Category: Chevy