Possible Reasons for Fuel Pump Issues & Troubleshooting:
1. Low Fuel: The simplest reason! Make sure the fuel tank has enough gas.
2. Fuel Pump Relay: The relay is an electrical switch that activates the fuel pump. Check the relay itself (location varies, consult your owner's manual or online resources for the 2003 Mustang GT) and try swapping it with a known good relay of the same type.
3. Fuel Pump Fuse: Similar to the relay, a blown fuse will stop the fuel pump. Check your owner's manual to find the fuel pump fuse location and check its condition.
4. Inertia Switch: Some vehicles have an inertia switch that cuts power to the fuel pump in a collision to prevent fire. This switch is usually located under the dash or in the engine bay (check your owner's manual). It might have a reset button; if so, push it.
5. Fuel Pump Failure: The fuel pump itself might be faulty. This requires replacing the fuel pump, a more complex repair.
6. Wiring Issues: A short circuit, corroded connection, or damaged wiring harness can interrupt power to the fuel pump. This requires careful inspection of the wiring.
7. PCM Problem: In rare cases, a problem with the PCM can prevent the fuel pump from activating. This requires professional diagnosis.
8. Security System Issues: While less likely, a malfunctioning security system could prevent the fuel pump from engaging.
What NOT to do: There's no procedure to "reset" a hypothetical fuel pump cutoff switch. Don't randomly disconnect or reconnect parts, as this could cause further problems.
Recommendation:
Before attempting any repairs yourself, consult your owner's manual. If you're not comfortable working on your car's electrical system, take it to a qualified mechanic. They can diagnose the problem accurately and perform the necessary repairs safely. Providing them with a description of the symptoms will help them troubleshoot effectively.
