2020 Nissan Altima Fuse Box Diagram

The 2020 Nissan Altima fuse box diagram is an indispensable resource for any owner looking to perform electrical repairs, install aftermarket accessories, or simply understand the intricacies of their vehicle's electrical system. Think of it as a roadmap to your car's electrical heart. Without it, navigating electrical issues can be a frustrating and potentially damaging endeavor. This guide provides an in-depth look at the Altima's fuse box, its components, and how to effectively use the diagram for troubleshooting and maintenance.

Purpose and Importance

Why bother with a fuse box diagram? Well, fuses are designed to protect your car's electrical components from overcurrent. When a circuit experiences excessive amperage, the fuse blows, interrupting the flow of electricity and preventing damage to more expensive parts. Without a diagram, you're essentially guessing which fuse controls which circuit, which can lead to:

Incorrect fuse replacement: Using the wrong amperage fuse can lead to further electrical damage, or even a fire.
Prolonged troubleshooting: Wasting time trying to identify the source of a problem without a clear understanding of the electrical layout.
Accidental damage: Potentially shorting circuits or damaging sensitive electronic components.

A detailed fuse box diagram allows you to quickly identify the correct fuse for a specific component, diagnose electrical faults, and perform necessary repairs with confidence. It's also incredibly useful when adding aftermarket accessories like lights, stereos, or remote starters, allowing you to tap into the correct circuits safely and efficiently. Learning the electrical layout can empower you to handle many common electrical issues yourself, saving time and money on mechanic visits.

Key Specs and Main Parts

The 2020 Nissan Altima typically has at least two fuse box locations:

Interior Fuse Box: Usually located under the dashboard on the driver's side. You may need to remove a small panel to access it.
Engine Compartment Fuse Box: Located in the engine bay, often near the battery. It's usually a larger, sealed box to protect the fuses from the elements.

Each fuse box contains a collection of fuses and relays. Let's break down these components:

Fuses: These are the sacrificial elements, designed to blow when a circuit is overloaded. They come in various amperage ratings (e.g., 5A, 10A, 15A, 20A, 25A, 30A, 40A), indicated by numbers printed on the fuse itself. Different fuse types might be used, such as blade fuses (the most common type), or cartridge fuses.
Relays: These are electromechanical switches that control higher-current circuits using a low-current control signal. They're often used for components like headlights, starter motors, and fuel pumps. A relay allows a small switch inside the car to control a powerful device without having to run heavy wires all the way to the switch.
Fuse Puller: A small plastic tool (often stored inside the fuse box itself) designed to safely remove fuses without damaging them or your fingers.
Spare Fuses: Many fuse boxes contain a selection of spare fuses of various amperage ratings for emergency replacements.

Understanding Fuse Box Diagram Symbols

The fuse box diagram isn't just a picture of the fuse box; it's a schematic that uses symbols and abbreviations to represent different components and circuits. Here’s what you need to know:

Lines: Lines represent electrical wires or circuits. Thicker lines might indicate higher current capacity.
Colors: Wire colors are often indicated next to the lines, using abbreviations like "BLU" (Blue), "RED" (Red), "BLK" (Black), "WHT" (White), "GRN" (Green), "YEL" (Yellow). These colors help you trace wires in the vehicle's wiring harness.
Icons: Icons represent the components powered by each fuse. Common icons include:
- Light Bulb: Headlights, taillights, interior lights.
- Fan: Radiator fan, blower motor.
- Coil: Relays, solenoids.
- Rectangle with zig-zag line: Heater element.
- Speaker: Audio system.
Amperage Rating: Next to each fuse location on the diagram, you'll find a number followed by "A" (e.g., 10A, 20A). This indicates the fuse's amperage rating, crucial for selecting the correct replacement.
Component Name or Abbreviation: The diagram will often label each fuse with the name of the component it protects, or a common abbreviation, such as "HEAD LP" (Head Lamp), "IGN" (Ignition), "FUEL PUMP," "A/C COMP" (Air Conditioning Compressor), or "ECU" (Engine Control Unit).

How It Works: Following the Circuit

Understanding how to "read" the diagram is the key to using it effectively. Imagine you have a problem with your car's cigarette lighter (or power outlet). Here's how you'd use the diagram:

Locate the Diagram: Find the fuse box diagram for your 2020 Nissan Altima. It's often located in the owner's manual.
Identify the Relevant Fuse Box: Determine whether the cigarette lighter fuse is located in the interior fuse box or the engine compartment fuse box. The diagram should indicate this.
Find the "CIG LTR" or "POWER OUTLET" Fuse: Scan the diagram for the fuse labeled "CIG LTR" or "POWER OUTLET." It might also be labeled something similar like "ACC" (Accessory).
Note the Amperage: Once you've found the correct fuse, note its amperage rating (e.g., 15A, 20A).
Locate the Fuse in the Fuse Box: Use the diagram as a guide to find the corresponding fuse location in the physical fuse box. The diagram should show the fuse's position relative to other fuses and components.
Inspect the Fuse: Using the fuse puller, carefully remove the fuse and inspect it. If the wire inside the fuse is broken or the glass is blackened, the fuse is blown.
Replace the Fuse: Replace the blown fuse with a new fuse of the same amperage rating. Never use a fuse with a higher amperage rating, as this could damage the circuit.

Real-World Use: Basic Troubleshooting Tips

Here are a few common troubleshooting scenarios where a fuse box diagram can be invaluable:

Component Not Working: If a particular component (e.g., headlights, radio, power windows) stops working, the first step is to check its fuse using the diagram.
Repeatedly Blowing Fuses: If a fuse blows repeatedly, it indicates a short circuit or an overload in the circuit. Do not just keep replacing the fuse with a higher amperage. This is a fire hazard. Use the diagram to trace the circuit and identify potential sources of the problem, such as damaged wiring or a faulty component. You may need to consult a qualified mechanic to diagnose and repair the underlying issue.
Adding Aftermarket Accessories: When installing accessories, the diagram helps you identify suitable circuits to tap into for power and ground connections. Always use a fuse tap to protect the new accessory and the existing circuit. Make sure that the accessory amperage requirements do not exceed the total capacity of the circuit.

Safety Precautions

Working with electrical systems can be dangerous. Here are some essential safety precautions:

Disconnect the Battery: Before working on any electrical components, disconnect the negative (-) terminal of the battery to prevent accidental short circuits.
Use Insulated Tools: Always use insulated tools to avoid electrical shock.
Never Bypass a Fuse: Never bypass a fuse with a wire or other conductive material. This eliminates the protection the fuse provides and can cause serious damage or a fire.
Be Cautious Around High-Current Circuits: Components like the starter motor, alternator, and main power feeds carry high current. Exercise extreme caution when working around these components. The airbag system fuses are also especially sensitive; tampering with them could cause unintended deployment.
Consult a Professional: If you're not comfortable working with electrical systems, or if you encounter a complex problem, consult a qualified mechanic.

We have a detailed 2020 Nissan Altima Fuse Box Diagram available for download. Having this diagram on hand will significantly aid in any electrical troubleshooting or modifications you plan to undertake. It's a valuable resource that will empower you to understand and maintain your vehicle's electrical system with greater confidence.