* Blown Fuse: Check the fuse for the fuel pump in the fuse box (under the hood, usually). Replace it if it's blown.
* Bad Fuel Pump Relay: The relay itself might be faulty. You'll need to locate the relay (consult your owner's manual or a wiring diagram; it's usually in the under-hood fuse box). You can try swapping it with a relay of the same amperage rating for another non-essential circuit (like the wipers) to see if the problem follows the relay. If the problem moves, the relay is likely bad. Replace it with a new one.
* Bad Fuel Pump: The fuel pump itself could be failing. This is the most expensive and difficult repair, often requiring tank removal.
* Wiring Issues: A broken wire or corroded connection in the fuel pump circuit could prevent power from reaching the pump. This requires tracing the wiring harness.
* Inertia Switch (if equipped): Some Cherokees have an inertia switch that cuts power to the fuel pump in a collision. Check to see if there's a reset button on this switch (often located under the dash or in the engine compartment).
How to *test* the fuel pump relay (NOT reset):
1. Locate the relay: Consult your owner's manual or a wiring diagram for the location and identification of the fuel pump relay.
2. Remove the relay: Carefully remove the relay from its socket.
3. Visual Inspection: Check the relay for any obvious signs of damage, such as burnt contacts or a cracked casing.
4. Check the relay with a multimeter (optional): If you have a multimeter, you can test the relay's continuity to confirm if it's functioning correctly. This requires understanding how to use a multimeter to test relays; search online for a tutorial.
If none of the above solves the problem, you'll likely need professional help from a mechanic to diagnose the issue. Remember to always disconnect the negative battery terminal before working on any electrical components.
