What is a car fuse box and where is it located?

A car fuse box is an electrical distribution center that houses fuses and relays protecting your vehicle's electrical circuits. Most vehicles have multiple fuse boxes: the main box is typically located under the hood near the engine, while the interior panel is usually under the dashboard on the driver's side or beneath the steering wheel. Consult your owner's manual or our fuse diagrams to find the exact location for your specific make and model. Knowing your fuse box location is essential for troubleshooting electrical problems and performing maintenance.

How do I read a fuse box diagram?

Fuse box diagrams show the location and amperage rating of each fuse and relay. Each position is numbered and labeled with the circuit it protects (headlights, wipers, power windows, etc.) and the fuse's amperage rating (5A, 10A, 15A, 20A, etc.). The diagram indicates whether positions contain fuses or relays. Color-coded fuses help identify amperage: blue for 15A, yellow for 20A, red for 10A, and brown for 7.5A. Our detailed diagrams include this information for every vehicle, making it easy to identify the correct fuse for any circuit.

What does an amperage rating mean on a fuse?

A fuse's amperage rating indicates how much electrical current it can safely handle before blowing. Common ratings include 5A, 7.5A, 10A, 15A, 20A, 25A, 30A, and 40A. Higher-amperage fuses protect circuits with greater power demands like the alternator or starter motor. Lower ratings protect sensitive circuits like dashboard lights or power windows. Never use a fuse with a higher amperage rating than specified, as this can allow excessive current through the circuit, creating fire hazards and damaging electrical components. Always replace blown fuses with the exact amperage specified in your vehicle's diagram.

Why does my fuse keep blowing?

A repeatedly blown fuse indicates an underlying electrical problem requiring investigation. Common causes include short circuits in wiring, failing electrical components, water damage in connectors, or improper installation of aftermarket equipment. Never simply replace the fuse multiple times without addressing the root cause. Start by checking the affected circuit for loose connections, damaged wiring, or burned components. If the problem persists, consult a professional mechanic. Our fuse box diagrams help you identify which circuit is problematic, allowing you to pinpoint the issue quickly and prevent vehicle damage or fire hazards.

How do I safely replace a blown fuse?

To safely replace a blown fuse: (1) Turn off the engine and all electrical systems. (2) Locate the fuse box using our diagram. (3) Find the blown fuse by examining the filament inside—a blown fuse appears darkened or broken. (4) Note the amperage rating on the fuse. (5) Remove the blown fuse using the provided fuse puller tool or carefully with your fingers. (6) Insert a new fuse with the exact same amperage rating. (7) Start the engine to verify the circuit works. If the replacement fuse blows immediately, don't replace it again—seek professional service. Our detailed diagrams ensure you find the correct fuse position quickly.

What's the difference between a fuse and a relay?

Fuses are passive protection devices that melt and break the circuit when current exceeds safe levels, preventing damage and fire. Relays are electromagnetic switches that control high-power circuits using low-power signals from switches. Fuses protect circuits from overcurrent, while relays switch circuits on and off or redirect power. Fuse boxes contain both components, and our diagrams identify which positions contain fuses and which contain relays. Understanding this distinction helps you troubleshoot problems: a blown fuse indicates overcurrent issues, while a relay failure causes the circuit to not respond to control switches.

Where can I find the fuse diagram for my specific vehicle?

ProCarManuals provides comprehensive fuse box diagrams for thousands of vehicle makes and models organized by year. Use our search feature to find your specific vehicle by make, model, and year. We cover Acura, Honda, Toyota, Ford, Chevrolet, BMW, Mercedes, Audi, and many other manufacturers. Each diagram shows the fuse box location, circuit labels, amperage ratings, and detailed explanations. Our guides help you quickly locate the fuse you need, understand circuit functions, and troubleshoot electrical problems. If you can't find your vehicle, contact our support team for assistance.

What electrical problems can I diagnose with a fuse diagram?

Fuse diagrams help diagnose non-functioning circuits by showing which fuse protects which system. If your headlights don't work, find the headlight fuse position in the diagram and check if it's blown. Same for power windows, wipers, interior lights, power seats, and other electrical features. A blown fuse indicates an overcurrent condition in that circuit. Non-blown fuses with non-functioning components suggest relay failure, wiring problems, or failed switches. Our detailed diagrams identify circuit names and their locations, allowing you to systematically troubleshoot electrical issues before seeking expensive professional service. Replace blown fuses with correct amperage ratings and investigate repeated failures.

Are fuse boxes the same in all model years of the same vehicle?

Fuse box layouts often change between model years, even for the same vehicle make and model. Engine updates, added safety features, new electrical systems, and design revisions cause manufacturers to modify fuse configurations. A 2020 Honda Civic may have a different fuse box layout than a 2015 Civic. ProCarManuals provides separate diagrams for each model year to ensure accuracy. Always consult the diagram for your specific year to find the correct fuse positions. Incorrect fuse selection from a different year could damage circuits or create safety hazards. Our organized, year-specific diagrams prevent these mistakes.

What should I do if my vehicle has multiple fuse boxes?

Most vehicles have at least two fuse boxes: the main underhood panel near the engine and an interior panel under the dashboard. Some vehicles have additional fuse boxes in the rear, under seats, or in other locations. Our comprehensive diagrams identify every fuse box location in your vehicle and provide separate diagrams for each one. The underhood box typically protects engine-related circuits (fan, fuel pump, ignition), while the interior box protects comfort and convenience features (windows, lights, wipers, seats). Identifying which fuse box contains the circuit you need prevents wasting time searching. Always consult all relevant diagrams when troubleshooting electrical problems in multi-box systems.

Can I use a higher amperage fuse to prevent future blown fuses?

Never use a fuse with higher amperage than specified. Doing so creates serious safety risks. Higher-amperage fuses allow excessive current through circuits designed for lower power, causing wire overheating, component damage, and potential fires. If a fuse blows, it indicates the circuit is drawing more current than safe, often due to shorts, failing components, or improper modifications. Installing a higher-amperage fuse masks the problem rather than solving it. Always replace fuses with the exact amperage rating shown in your vehicle's fuse diagram. If a replacement fuse blows immediately, investigate the underlying electrical fault. Professional diagnosis prevents damage and ensures vehicle safety.

Holden Astra Sedan (BL) 2017-2018 Fuse Box Diagram – Location, Fuses & Relay Assignments

By Todd Mitchell

On: Saturday, May 24, 2025 6:45 PM

holden astra sedan bl 2017 2018 fuse layout

This article covers the seventh-generation Holden Astra sedan (BL), produced from 2017 to 2018. Here you will find the Holden Astra BK 2017 and 2018 fuse box diagrams, get information on the location of the fuse boxes in the car and learn about the assignment of each fuse (fuse layout).

Passenger Compartment Fuse Box

Fuse Box Location

The fuse box is located behind a cover. Pull the cover and remove.

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Fuse Box Diagram

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Assignment of the fuses in the instrument panel

№	Circuit
1	ABS
2	Cigarette lighter
3	Power outlet front
4	Climate control system, fan
5	Power window front
6	Body control module
7	Heated seat
8	Exterior mirror / rain sensor / lane keep assist / high beam assist
9	Power seat, driver side
10	Power window rear
11	Body control module
12	Passive entry / passive start
13	Body control module
14	Central locking system, boot lid
15	Sunroof
16	Body control module
17	Body control module
18	Data link connector
19	–
20	Diagnostic module
21	Climate control system
22	Occupant sensor
23	Clock spring
24	Ignition switch / engine steering column lock
25	–
26	Parking assist / Infotainment system
27	–
28	Navigation module
29	Instrument cluster
30	Infotainment system, radio
31	Body control module
32	Body control module
33	–
34	Shifter / PRNDL
35	–
36	–
37	Audio amplifier

Engine Compartment Fuse Box

Fuse Box Location

The fuse box is in the front left of the engine compartment. Disengage the cover and remove it.

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Fuse Box Diagram

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Assignment of the fuses in the engine compartment

№	Circuit
1	Washer front / washer rear
2	Air conditioning clutch
3	Starter
4	–
5	High beam LH
6	High beam RH
7	–
8	Horn
9	–
10	–
11	–
12	Even bank
13	Odd bank
14	Exhaust sensor
15	Exhaust sensor
16	–
17	–
18	Front wiper
19	–
20	Engine control module
21	Starter
22	–
23	–
24	ECM
25	–
26	Transmission control module
27	Front fog light
28	–
29	–
30	–
31	ECM / TCM ignition
32	Water in fuel sensor / switchable water pump
33	Trailer provision
34	Flex fuel sensor
35	–
36	VAR_FUNC
37	Headlight leveling device
38	–
39	Fuel pump
40	–
41	–
42	Interior mirror
43	–
44	Steering wheel heating
45	Canister vent
46	Instrument cluster
47	Anti-theft alarm system
48	Rear heated seat
49	Electrical steering column lock (ESCL)
50	–
51	Central gateway
52	Mirror defog 1
53	Rear window defog
54	–
55	Mirror defog 2
56	–
57	ABS pump

Load Compartment Fuse Box

Some fuses are located near the vehicle battery.

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№	Circuit
1	Engine control module
2	Fuel supply
3	Power supply