Make sure connections are on tight.
Mitsubishi Lancer Evolution X... (10)
if its a modern jeep it probably needs to have its immobilizer reset after changing the battery ask a main dealer
If you mean the fuel pump assembly yes. Fuel assembly is vague. But I assume you are referring to the fuel pump and float assembly that lives in your gas tank. There was a recall on some of the Xterra's because the wiring to the assembly was not protected well, the wiring would break and cause the Xterra's to die while driving without warning or you would come out to start your car and it just wouldn't start. You can call a dealer and give them your vin # to check and see if this recall has been performed on your vehicle.
Your battery is not charging. It is either due to a faulty battery or a faulty alternator. Get it changed.
have you replaced and or tested both coils? are you getting no spark on the intake and the exaust sides?
Catalytic converter gone bad
It should be no different than before. Just start it up. If it want start make sure the cables are tight. If this doesn't help you got other problems.
Xterra - Nissan SUV XKE - Jaguar
To reset the computer on a Nissan Xterra, start by disconnecting the negative terminal of the battery and leaving it disconnected for about 10-15 minutes. This allows the computer to reset and clear any stored error codes. After the time has elapsed, reconnect the negative terminal and start the vehicle; the computer will reinitialize. If needed, you can also use an OBD-II scanner to clear codes more directly.
Mitsubishi Lancer Evolution X... (10)
Check the charge on your alternater.
Signs of a bad starter on a 2006 Nissan Xterra include a clicking sound when you turn the key, a complete lack of response (no sounds or lights), and intermittent starting issues where the engine may start occasionally but not consistently. Additionally, if you hear a grinding noise while trying to start the vehicle or notice that the dashboard lights dim significantly when attempting to start, these could also indicate a failing starter. If these symptoms occur, it’s advisable to have the starter tested or replaced.
To replace the oil pressure switch on a 2000 Nissan Xterra, start by ensuring the engine is cool and disconnect the negative battery cable. Locate the oil pressure switch, typically found near the oil filter on the engine block. Use a socket wrench to remove the old switch, then install the new one by tightening it securely and reconnecting the electrical connector. Finally, reconnect the battery cable and check for leaks after starting the engine.
To take apart the headlight assembly on a 2004 Nissan Xterra, start by disconnecting the negative battery terminal for safety. Remove the screws securing the headlight assembly, typically located on the top and side. Gently pull the assembly forward to detach it from the vehicle, being cautious of any clips or wiring harnesses. Once removed, you can access the bulbs and other components for replacement or repair.
dead battery
Check the battery cables or starter.
Starter lockout relay, next to the battery.