* Online Repair Manuals: Sites like RepairManual.com or AutoZone.com (often requires a paid subscription or purchase). These often have downloadable diagrams. Search specifically for your year, make, model, and *engine size*. Engine size is crucial for accurate diagrams.
* Nissan's Website (Possibly): Nissan's official website might have some diagrams available, but this is less likely for a vehicle that old. They may offer service manuals through their dealer network for a fee.
* eBay or Amazon: You can sometimes find physical copies of repair manuals or CDs containing wiring diagrams on these sites.
* Local Auto Parts Stores: Places like AutoZone, Advance Auto Parts, or NAPA Auto Parts may have access to wiring diagrams on their computers, either for free or as a print-out for a small fee. Again, be ready to give them the exact details of your truck.
* Haynes or Chilton Repair Manuals: These are widely available at auto parts stores and online. They often include wiring diagrams, though they might not be as detailed as factory manuals.
Important Tips:
* Specify your exact truck model: Saying "1996 Nissan pickup" is too vague. You need the specific model (e.g., Hardbody King Cab, Frontier XE, etc.) and engine size (e.g., 2.4L, 3.0L V6).
* Be prepared to pay: Factory-level service manuals are usually expensive. Third-party options (Haynes, Chilton, online resources) are usually cheaper but might offer less detail.
* Safety First: Working with car electrical systems can be dangerous. If you're not comfortable, consult a professional mechanic.
Remember to always disconnect the negative battery terminal before working on your vehicle's electrical system.