Electrical Issues:
* Blown fuse: Check the fuse box for a blown fuse related to the fuel pump.
* Relay failure: The fuel pump relay acts as a switch. A faulty relay will prevent power from reaching the pump. Replacing this is often a cheap and easy first step.
* Wiring problems: Corroded, broken, or loose wires in the fuel pump circuit can interrupt the power supply. Inspect the wiring harness from the relay to the pump, looking for damage or poor connections.
* Inertia switch activation: Some vehicles have an inertia switch (a safety device that cuts power to the fuel pump in a collision) that might have tripped. Locate and reset it if present (often found under the dash or in the engine compartment).
* Fuel pump relay circuit issues: The relay circuit can have problems beyond just the relay itself. Issues like corroded connections or damaged wires within the circuit could cause the relay to not activate correctly, or even if it does activate, power may still not reach the pump.
* Bad ignition switch: A malfunctioning ignition switch can prevent power from reaching the fuel pump circuit.
Mechanical Issues:
* Fuel pump failure: The pump itself might have simply worn out or burned out due to age or overuse. This is the most common cause.
* Fuel pump filter blockage: A clogged fuel filter restricts fuel flow, causing the pump to work harder and potentially fail.
* Low fuel level: While seemingly obvious, an extremely low fuel level can sometimes prevent the pump from drawing fuel efficiently, causing it to overheat and fail.
Other Issues:
* Power module failure (PCM/ECM): In some cases, a faulty Powertrain Control Module (PCM) or Engine Control Module (ECM) can prevent the fuel pump from receiving the signal to operate. This is less common than the electrical issues mentioned above, but it's a possibility.
* Security System issues: Some vehicles have security systems that will disable the fuel pump if a problem is detected. A faulty alarm or immobilizer could potentially cause this problem.
Troubleshooting Steps:
1. Check the fuse: This is the easiest and cheapest first step.
2. Inspect the relay: Swap it with a known good relay (or replace it).
3. Check the fuel level: Ensure you have enough fuel in the tank.
4. Inspect the wiring: Look for any visible damage to the wiring harness.
5. Check the inertia switch: Reset it if it's tripped.
6. Listen for the fuel pump: Turn the ignition key to the "ON" position (don't crank the engine). You should hear a brief whirring sound from the fuel pump. If you don't, that points towards an electrical issue.
If none of the above solves the problem, it's likely that the fuel pump itself has failed and needs replacement. Remember safety precautions when working with fuel systems - disconnect the battery negative terminal before working on any electrical components, and be mindful of fuel fumes. If you're not comfortable performing these repairs yourself, consult a qualified mechanic.
