The PCM receives signals from various sensors (crankshaft position sensor, camshaft position sensor, etc.) and the ignition switch. When the ignition key is turned to the "ON" or "START" position and the PCM determines the conditions are right (engine is cranking or running), it energizes the fuel pump relay. This relay then sends power to the fuel pump.
Therefore, you won't find a dedicated switch for the fuel pump. Troubleshooting a fuel pump issue would involve checking:
* The fuel pump relay: This is a much more common point of failure and is usually located in a fuse box under the hood or in the interior. Your owner's manual or a repair manual will show you the exact location.
* The fuel pump circuit wiring: This involves checking for power at the pump itself, and tracing the wiring back to the relay and PCM.
* The PCM itself: While less common, the PCM could be faulty, but this is usually diagnosed by a mechanic using specialized tools.
* The inertia switch: This is a safety device that cuts power to the fuel pump in the event of a collision. It's usually located under the dash or in the trunk, and often has a reset button.
In short: There's no single switch to directly control the fuel pump. The system is much more sophisticated. If you're having fuel pump problems, consult a wiring diagram and/or a qualified mechanic.
