1. Safety First:
* Disconnect the negative battery terminal. This is crucial to prevent electrical shocks and potential fires while working on the electrical system.
2. Visual Inspection:
* Examine the fuse: Make sure you're using the correct amperage fuse. Check the fuse holder itself for any signs of melting, corrosion, or damage.
* Check all wiring: Inspect all the wiring related to the fuel pump for any signs of fraying, chafing, or damage, particularly near the fuel tank and the engine compartment. Look for any wires that might be touching metal parts of the car (grounding out). Pay close attention to areas where wires might rub against moving parts.
* Fuel pump relay (if applicable): Some vehicles use a relay for the fuel pump. Locate the relay (check your owner's manual or online forums for its location) and visually inspect it for damage. If you have a spare relay, you can try swapping it out to see if that solves the problem.
3. Testing (Requires a Multimeter):
* Check the fuel pump relay (if applicable): A multimeter can confirm if the relay is working correctly.
* Check for shorts: Using your multimeter, carefully test the wiring harness for shorts to ground. This requires some electrical knowledge; if you're not comfortable with this, seek professional help. You'll be looking for a low resistance reading (close to zero ohms) between the wire and a ground point (unpainted metal on the car's chassis).
4. Potential Causes:
* Short in the wiring harness: This is the most likely culprit. A short can be anywhere along the wire running from the fuse box to the fuel pump.
* Faulty fuel pump: A shorted fuel pump motor will draw excessive current, blowing the fuse.
* Fuel pump relay failure (if applicable): A faulty relay will also cause the fuse to blow.
* Fuel level sensor: In rare cases, a faulty fuel level sensor can cause a short.
* Corrosion: Corrosion in connectors can cause high resistance and lead to excessive current draw.
5. What to Do Next:
* If you find a damaged wire: Repair or replace the damaged section of wiring. Use proper automotive-grade wire and connectors.
* If you find a short in the wiring harness: Repairing this is complex and may require professional assistance.
* If you suspect a faulty fuel pump: Replacing the fuel pump is a more involved task that usually requires dropping the fuel tank. This is best left to a qualified mechanic.
Recommendation:
Unless you have significant experience working with automotive electrical systems, it's highly recommended that you take your 1999 Dodge Neon to a qualified mechanic. Continuing to troubleshoot without proper knowledge could lead to further damage or injury. The cost of professional diagnosis and repair will be far less than the cost of a potential fire or more extensive damage.
