Which fuse controls the cigarette lighter?

The cigarette lighter is typically protected by a fuse labeled CIG LTR, CIGARETTE LTR, or PWR OUTLET in the interior fuse box, usually 15A (some models use 20A or have separate fuses for front and rear outlets). This article explains how to identify the correct fuse and what to do if it fails.

Where to look for the fuse

Locating the correct fuse is straightforward if you know how fuses are labeled and where the interior fuse box is located. The following steps guide you to the right fuse.

• Consult the owner's manual for fuse names and exact locations for your model and year.


• Check the fuse box cover or the nearby fuse diagram, which typically lists fuses by circuit name and amperage.


• Look for fuses labeled CIG, CIG LTR, LTR, PWR OUTLET, or POWER OUTLET; some vehicles use the term “12V Outlet.”


• Note that some cars designate separate fuses for front and rear power outlets, so you may see more than one fuse for outlets.


• Interior fuse boxes are commonly found under the dash on the driver's side, but some models place them in the glove box or center console; a second box may exist in the trunk for rear outlets.

Following the diagram on your fuse box cover will help you identify the exact fuse and amperage for your lighter socket.

Troubleshooting and replacing the fuse

If your lighter isn’t working, start with a fuse check and a controlled test to avoid misdiagnosis. The steps below provide a practical process.

Before you begin the steps, ensure the vehicle is off and you’re using the correct replacement fuse of the same amperage.

1. Power off the vehicle and unplug any devices from the lighter to prevent current draw during testing.


2. Open the interior fuse box and locate the fuse labeled CIG LTR, CIG, or PWR OUTLET using the diagram on the cover; remove the fuse with a fuse puller or small pliers.


3. Inspect the fuse: a blown fuse typically has a broken filament or a darkened appearance inside the clear plastic; if you’re unsure, swap it with a known-good fuse of the same rating to test.


4. If the fuse is blown, replace it with a fuse of the same amperage rating (commonly 15A, sometimes 20A). Do not replace with a higher rating unless the manual specifies otherwise.


5. Reconnect the lighter or a known-good 12V accessory and test; if it works, the problem was the fuse; if it blows again, there may be a short or excessive draw in the outlet circuit.


6. If replacement fuses continue to blow, or you can’t locate the right fuse, seek professional help from a qualified mechanic or automotive electrician to inspect wiring and any connected devices.

Regular maintenance and cautious use of 12V accessories can prevent most fuse-related outages in this circuit.

Summary

In most passenger cars, the cigarette lighter is controlled by a fuse labeled CIG LTR or PWR OUTLET in the interior fuse box, typically rated at 15 amps but sometimes 20 amps or separate for multiple outlets. Always verify with the owner’s manual and the fuse box diagram, and replace with the same amperage. If problems persist, professional diagnosis is advised.

How do I know if my plug fuse is blown?

You can tell if a fuse is blown by looking for a visible break in the wire or signs of melting/discoloration inside the glass, or by using a multimeter to test for continuity. A working fuse will show a continuous metal strip with no breaks, while a blown fuse has a broken or melted wire. A multimeter will show a low resistance reading (or beep on the continuity setting) for a good fuse and an "OL" (over limit) or no beep for a blown fuse.
 
This video explains how to check a fuse using a multimeter: 57sproclaimliberty2000YouTube · Jul 6, 2020
Visual inspection

• Look for a broken wire: A healthy fuse has a continuous metal strip. A blown fuse will have a visibly broken or melted metal strip inside the glass. 
• Check for discoloration: Look for a black or cloudy residue, discoloration, or a dark brown stain inside the glass, which indicates that the fuse has overheated. 
• Look for a burnt smell: A burning smell coming from the plug can also indicate a blown fuse. 
• Note: Some plug fuses have a spring-loaded mechanism visible through the glass. If this spring is fully retracted, the fuse is likely blown, as shown in this YouTube video. 

Multimeter test

• Set the multimeter: Set your multimeter to the continuity or resistance (Ωcap omegaΩ) setting. 
• Test the meter: Touch the two probes of the multimeter together; it should beep or show a reading close to zero. This confirms the meter is working correctly. 
• Test the fuse:
  • Place the probes on each of the metal ends of the fuse. 
  • A good fuse will produce a beep or a low resistance reading. 
  • A blown fuse will not beep or will show an "OL" (over limit) reading. 

You can watch this video to learn how to test a fuse with a multimeter: 15sConquerall ElectricalYouTube · Dec 26, 2023
If the fuse is blown

• Replace the fuse with a new one that has the exact same amperage rating as the old one. 
• If the problem continues after replacing the fuse, consult an electrician, as there may be another issue with the circuit. 

What fuse to use for 12V?

Let's say you have a device that uses 120 W in a 12vt. System the calculation would be. I = 120 W / 12 V equ= 10 A. Since devices can experience short power surges. We need to add a safety margin.

What powers the cigarette lighter in a car?

A car cigarette lighter has a nominal voltage rating of 12 volts but is limited to 10.2 volts with a maximum current of 10 amps. It can efficiently function as an outlet in cars and is used to provide power to a wide range of devices, such as radios, mobile phones, and laptops.

How to tell which fuse is which?

To know what each fuse is for, consult the fuse box diagram in your vehicle's owner's manual or on the fuse box lid itself. These diagrams show the location and function of each fuse, such as "low beam headlights" or "blower motor". If labels are unclear, use a test light or multimeter to test each fuse for power and identify which circuits are live. 
Using the fuse box diagram

• Check the owner's manual: Look for a section on fuses or fuse boxes to find the diagram. It will often list the components protected by each fuse, as shown in this YouTube video. 
• Look for labels on the fuse box: The fuse box, often in the engine bay and/or inside the cabin, may have a diagram printed on the cover or inside of it. Note that some fuses may protect more than one circuit, leading to confusion. 

This video explains how to locate and identify a fuse box and its diagram: 44sCars SimplifiedYouTube · Sep 5, 2020
Using a test light or multimeter 

• Turn the ignition to the "on" position (engine off) to activate most circuits. 
• Connect the ground clamp of your test light to a good ground source, such as the negative battery terminal or a bare metal body bolt. 
• Test each fuse: Place the test light probe on the metal test terminal on each side of the fuse. 
• Identify a blown fuse: A blown fuse will only have power on one side. A good fuse will have power on both sides, as shown in this YouTube video. 

This video demonstrates how to test fuses using a test light: 1m4DIYersYouTube · Apr 2, 2021
Other methods

• Try the device: If you're trying to diagnose a specific non-working device, try pulling fuses one by one and testing the device after each pull. This can be a time-consuming method. 
• Consult a wiring diagram: For more complex issues, a vehicle-specific wiring diagram provides the most detailed information.