How To Hook Up A Car Stereo To AC Power – You CAN Do It!

Want to use your car stereo at home? Great news – it’s actually not that hard…if you know what you’ll need.

In this article, I’ll show you how to hook up a car stereo to AC power along with:

  • What you need to know first
  • Clear & easy-to-follow wiring diagrams
  • What kind of AC power adapters or supplies you can use
  • How to wire a computer power supply to a car radio

…and more! There’s no reason to wait so let’s get started.

First things first: can you hook up a car stereo to a house outlet?

Can you hook up a car stereo to a house outlet image

The quick answer is yes, with the right power supply, you can hook up a car stereo to a house outlet with 120V or even 220V power. You cannot, however, directly connect a car stereo to an outlet.

However, you’ll need to know just a few things to make sure you don’t have any headaches or potentially destroy your car stereo.

Is a car radio AC or DC?

Car radios use direct current (DC) voltage to power their electronics while home electronics use alternating current (AC) with a much higher voltage. In fact, car radios can work down to somewhere around 11 volts DC, with 12V to 14.4V being typical when a vehicle’s engine is running.

The reason car radios use DC power is because automobiles use a DC battery to start and power the engine. While the motor is running an alternator generates AC power that’s changed to DC in order to charge the battery. Batteries store DC power, not AC.

What voltage do home outlets use?

Home AC outlets supply around 120V (volts, or “V”) AC if you’re in the United States and some other countries. Others I’ve been to are even higher at 220V AC. It’s extremely dangerous to try and connect a DC device to AC power – in fact, it can even explode or catch on fire.

What you need is a power supply to safely reduce the high voltage of a home AC outlet to a lower DC voltage that a car stereo can use.

How many amps does a car stereo draw?

The good news is that unlike car amplifiers, a car stereo draws only a few amps. Typical car stereos (depending on the design, features, etc) draw about 2 to 5 amps or so at full power.

I’ve seen some units that have a 10 amp fuse, but that doesn’t mean they use quite that much current. Fuses come in certain sizes so that’s the next closest one the manufacturer needed to use.

Although car stereo manufacturers may advertise them with high power ratings like “50W peak per channel”, in reality, the average car stereo can only put out about 15 to 18 watts RMS per channel.

That’s because they have to work with a +12V supply which limits the power they can deliver.

What is the 12V accessory wire on a car stereo?

Example of car stereo wiring harness power colors, labeled

Car stereos have 3 power wires that have to be connected in order to work:

  1. Ground/negative, “GND”
  2. +12V power/radio memory backup “BATT”
  3. Accessory on, “ACC”

For 99% of car stereo, the 12V accessory wire is a red-colored signal wire that triggers the electronics to switch on. They’re normally connected to a vehicle’s ignition switch accessory wire to turn on and off with the switch. 

It’s necessary to connect this to power on a car stereo. When power is removed from the radio’s accessory wire it turns off and goes into a low power mode.

What can I use to power a car stereo at home?

Car stereo AC-DC power supply examples image

The good news is that 12V power supplies are available if you look in the right place – and one that’s right for hooking up a car stereo to AC power shouldn’t cost much. You just need to know what to look for.

The good news is that it’s usually not hard to find the right kind of supply to power a car stereo at home. You’ll need one with 2 main things:

  • The right voltage: 12V to 13.8V
  • The right current (amps) rating: about 2 to 2.5A for most car stereos and towards 5A for some units that draw more
Tip: 12V supplies will work fine and are also the most common kind. 13.8V AC-DC supplies are used sometimes for powering CB radios and other equipment, so they’ll work fine but aren’t necessary. Don’t go out of your way to use those.

12V supplies are usually a lot more affordable anyway.

You can pick up an AC-DC supply from a variety of places: Amazon, your local electronics store, and you can even use an old PC computer supply (also called an “ATX” supply) you’ve got lying around. I’ll cover that in more detail later.

Can you use a wall adapter for a car stereo?

AC-DC wall outlet adapter example with barrel connector

While you can use a wall adapter to power a car radio with decent results, most are pretty poor and can’t supply many amps and only a little bit of power. You’ll also need to cut the wiring which in some cases can be a little tricky since it’s sometimes very small wire.

Technically, you can use a wall outlet AC-DC 12V adapter, but I don’t recommend it. 

They’re pretty limited in power output and the amperage they can provide (many are less than 1A rated). They’re designed to do things like charge devices or supply low-power devices.

They also don’t have good reserve power and when you start cranking up your car radio the voltage may begin to sag (drop out) and it won’t work well along with the sound breaking up & distorting. You’ll need to find one with enough current (say 2 to 2.5 amps or more if possible) and cut the wiring since most come with a connector attached.

Caution! When using a AC/DC wall adapter, be careful because for some it can be hard to tell which wire is positive and which is negative. 

Always be 100% sure before connecting a radio to avoid a reverse polarity condition as that can damage electronics!

What to know about computer power supplies

Computer power supply 12V current rating examples

PC power supplies are also called “ATX” supplies and can provide lots of current from their 12V wiring. You can see their amps rating on the label like in these examples above.

Computer power supplies are fairly common and are usually priced pretty well (especially used). You won’t need a high-power one.

In fact, even a standard low-end 150W PC power supply will work great for a car stereo! Nearly all of them have more current output than you need.

The drawback, however, is that PC power supplies require a certain (but easy to do) wiring connection in order to turn on. That’s because they’re normally connected to a PC motherboard that provides a control signal for them to work.

Fortunately, there’s an easy workaround you can use that makes them great for a home car stereo system power source.  See my detailed diagram for that further below. 

How do you hook up a power supply to a car radio?

How to wire a car stereo to power & speakers at home diagram

Connecting radio power and ground

To connect a car radio to a power supply you’ll need to do the following:

  • Ground: Connect the radio’s ground wire (black wire) to the (-) power supply output
  • Main power: Connect the radio’s +12V battery wire (usually the yellow wire) to the (+) power supply output
  • Turning the radio on: You can do this by hardwiring the radio’s accessory wire (usually red) to the +12V battery wire or you can use a switch in between.

If you hardwire the accessory wire to the yellow wire (battery power), you can turn the car stereo off with the power supply on/off control. However, while that’s very easy, it comes with a price.

Removing power from the 12V battery wire means the unit will lose its radio tuner settings, audio settings, and any other adjustments you’ve made. Optionally, using a switch to connect the accessory wire as an on/off control is a good idea. Leave the power supply on in this case.

Another way is to simply turn the radio on/off using the power button and leave the power supply on. In either case, when turned off the radio will go into a low-power mode draw less than 0.5 amps when shut off.

Connecting the speaker wiring

Car stereos usually use standard wire colors for speaker connections:

  • White = Front left +, White/black = front left –
  • Gray = Front right +, Gray/black = front right –
  • Green = Left rear +, Green/black = left rear –
  • Violet = Right rear +, Violet/black = right rear –

Just like power wiring colors, not all brands follow these standard colors so always check first!

Remember that car stereos can’t handle a speaker impedance (Ohms speaker load) below 4 ohms. You can, however, use 8 ohm home stereos speakers although you’ll only have 1/2 the rated output power available. I’ll explain that further below.

Never connect 2 ohm speakers for example or wire speaker outputs together as the radio can become hot and permanently damaged. Car stereos aren’t designed to be bridged like a car amp.

How to wire a computer power supply to a car stereo

How to wire a computer power supply to a car stereo diagram

Using an ATX (desktop computer) power supply for a car stereo isn’t hard – in fact, you only need a few steps:

  • Power connections: Cut a +12V wire (yellow) and a ground (black) wire from the main connector. Strip the insulation to leave about 3/8″ to 1/2″ bare wire. Use a crimp connector, solder, or another connector type to join the power supply’s +12V output (yellow) to the radio’s +12V battery wire (yellow). Do the same for the ground wires (black).
  • Supply on control: PC supplies don’t turn on even if the on/off switch on the case is used. A PC motherboard uses a control signal to the “supply on” wire pin. To do the same, you’ll need to find, cut, and jumper this control signal wire to a ground wire either directly or with an on/off switch if you like [See diagram above]
  • Radio accessory wire: Connect the radio’s accessory/on wire (red) to the +12V power wire from the supply either directly or you can use an on/off switch if you like.

Once you’ve connected the +12V and ground wiring to the radio, connect the “supply on” wire shown above to another ground wire as shown. The supply should start and your car radio should turn on. 

As I mentioned earlier, switching off the power supply will cause the radio to lose its “memory” (settings, last station you played, etc) so you may find it easier to use an on/off switch on the accessory wire or turn the radio on & off using the power button.

Don’t forget that a radio uses only a tiny bit of power when turned off so you can leave your power supply running if you like.

How to connect car stereo wires together properly

You’ve got several options for how to connect car stereos wires together properly. I’ll cover a few here. These are:

  1. Using the twist-and-tape method (not something I recommend, but it works “in a pinch”)
  2. Using connectors such as crimp (“butt”) connectors or wire nuts
  3. Soldering the wires together

I’ll cover each in detail.

1. Connecting wire using the twist-and-tape method

Example of speaker wire extended by twisting and wrapping with tape

Although it’s easy to do and cheap (especially if you don’t have many tools around), it’s the least reliable way to connect speaker or car stereo wires together. In my experience, the tape can come off later or the twisted wire may work its way loose at some point.

It’s as easy to do as:

  1. Strip about 1/2 inch insulation from the end of each wire
  2. Twist the bare wire together as tightly as possible, wrapping around each other to help hold them together
  3. Tear off some electrical tape and tightly wind it around the exposed wire and also the wire insulation

2. Connecting wire using crimp connectors

How to use crimp connectors with wire instruction steps image

This is one of the most reliable ways to connect wire and one I’ve used for years for car stereo installations. You’ll need one or more tools to strip your wire and crimp the connectors.

Here’s how:

  1. Strip the wire leaving 3/8″ to 1/2″ bare wire exposed.
  2. Tightly twist the wire so it can be pushed into the connector properly.
  3. Insert the wire into one end firmly, pushing it into the metal contact inside. Be sure to insert it fully.
  4. Place the connector into the crimp tool in the appropriate position in the tool, near the end of the connector.
  5. Crimp very hard with the tool to make press the connector down hard, holding the wire inside permanently.
  6. Repeat the same for the other side & you other wires as needed.

Tip: For best results, once you’re done pull gently on the wire while holding the connector. The wire shouldn’t come out. If it does, you’ve crimped it poorly and will need to do it over again.

Image showing example crimp tool and crimp connectorsExamples of a wire crimping & stripping tool and crimp (“butt”) connectors. Blue is one of the most common and works well with 18AWG wire.

When shopping for crimp connectors you’ll notice they’re available in different colors for different gauges of wire. In most cases, the blue ones are fine for car speaker & radio wiring use. You can also pick up an affordable set that includes the crimp tool and connectors as well.

3. Connecting wire by soldering

Image showing steps for how to solder speaker wire

This is hands-down the most reliable way to extend & splice wires as when done properly soldered wire is extremely strong and is permanent.

How to solder car stereo wires

  1. Cut & strip the wire (at least 1/2″ length of bare wire is needed).
  2. Hold up both ends to form an “X” shape with the wire facing opposite directions.
  3. Hold both ends and tightly twist each end around the other until they’re completely wrapped over each other.
  4. After the soldering iron is hot, apply heat to the wire with the tip. Once heated (after a few seconds usually), apply solder enough so that it has flowed fully through the wire.
  5. Rotate the wire to the other side and apply the solder until all of the wire is fully saturated with solder.
  6. Allow the wire to cool for a few moments.
  7. Tear 2 short pieces of electrical tape. Starting at the insulation and at an angle, tightly wrap the tape until it is fully covered.

It’s important to fully cover the wire once you’re done. That’s to prevent adjacent wires from touching each other and causing a short circuit that can permanently damage the radio’s output stages.

How long does soldering speaker wire properly take?

All in all, you’ll need about 30 minutes to solder a full set of car radio power & speaker wires or a bit less if you’re only connecting the power side.

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Got questions or comments?

You can leave a comment below or reach me directly via my Contact page. Thanks!

Your comments are welcome!

  1. Hey, i recently changed my car stereo that someone had put in my house with a newer and better car stereo, and i notice that i get 12v to the chassi of the stereo, why is this? is it how it should be? they used a 12v transformer and minus and plus is connected correctly. i live in Sweden btw.

    • Hi, it’s a bit hard to say without more info, but the only way that would normally be possible is if the leads are reversed. Are you sure you are correctly measuring the voltage?

      It really shouldn’t be (ordinarily) possible for the chassis, which is normally connected to ground, to have +12V. If the radio has a different configuration it’s possible it’s “floating” (not grounded or connected) and giving that result. I would measure continuity or Ohms from the chassis to the negative power wire with the power remove. Most of the time we us an AC-DC power supply to supply car stereos indoors as they provide a stable, smooth +12V and ground output.

      A transformer also needs a rectifier and smoothing components to work best. Switching power supplies do this as well. If the 12V source is not a real power supply then there may be other factors at work.

  2. Hey Marty,

    I did it the way you did (and added the orange wire for lighting to the 12v+). Only when I enter the code of my radio (Ford 6000CD RDS-EON) it resets and I need to enter the code again. It is not faulty since no number of faults appear. It shuts off and on directly.

    Do you know why this could happen?



    • Hi Kevin. Are you sure you’ve got the wiring correct? If you’re going by the wiring colors on a factory stereo, they’re almost never the same as aftermarket stereos. Aftermarket stereos *generally* use standard colors, but factory head units do not.

      The illumination wire is often optional as well and not needed for a radio to function in most cases. If you can try wiring only ground, +12V battery (“memory” wire), and the accessory wire (+12V ignition) and see what happens then. If you’re using a factory head unit you may need to find the factory wiring color codes first. Best regards!

  3. Hi Marty,
    In order not to lose memory, settings, time on the car stereo, etc, pc power supply should stay on all the time?

    • Hi Marian. Yes that’s correct. If your power supply is large and you’re concerned about leaving it running all the time, you can also connect a small +12V adapter to the main one using diodes to save energy when the radio/main supply isn’t in use.

      (Not hard to do but a separate topic)

  4. Hi Marty,

    Nice, informative article. I’ve been doing this with my old car stereo for years. Of course I had to step mine up a notch to also run a 600W amplifier for the 12″ subs so my workshop really rocks :).
    Strong enough ATX power supplies get pretty expensive so I went the server PS route instead. The HP Proliant PS I have puts out about 12V @ 75A and cost about $40 for a refurbished unit.
    I had found a great source for server PS conversion since they are not the same as ATX PS wiring.
    Anyway, keep up the good work.

    • Hi Ken. Thanks for the helpful info! That’s a great option and I’ll let people know.

      You’re right, $40 for a 75A supply is a steal. That’s awesome. :)

      Best regards!

  5. Great article! I had looked into doing this before, several months ago, and I found a few articles on this that left me looking for a radio mp3 player (seriously hard to find one with similar features to a car’s radio). Your article, however explains everything clearly enough for me to feel confident in doing this.

    Small question:
    “Removing power from the 12V battery wire means the unit will lose its radio tuner settings…”

    Could a 12V battery be attached on this line to save settings, or would this overcharge the battery and cause a fire or burn out? Could a battery charger such as have it’s prongs “plugged” soldered into line to avoid that?

    12V line: Supplies primary power?
    ACC: A logic gate as such? if V == 1, Radio = On; else Radio = 0
    Ground: Neutral

    • Hi, well you can’t use a battery charger like that anyhow. NiCad AA cells like that are below 1.5V each. You’ll need close to 12V to maintain battery-backed memory in car stereos.

      You could use a 12V battery connected in series with a diode for one idea, or use a 2nd (very small) 12V AC-DC supply with 1A or less output connected with a diode to keep the battery wire live while avoiding damage to it when the main supply is switched on.

      The +12V memory connection draws very little current typically (.025A for example)

      • Marty Thank you for the great idea of using a very small 12VDC supply to keep the battery wire live . I built a massive 12 VDC power supply with 10, 000 mf capacitors for filtration , for my set up and was wondering how to keep from loosing the radio settings when the unit was off . I could leave the powers supply on and just turn off the radio , but not sure what current it would still draw. The power supply idle current would probably be more than the radio memory. In retrospect I wish I knew about the old computer power supplies .

        • I may try a 9 volt battery with a diode to maintain the memory ( in reality 8.4 Volts with diode loss ) , but not sure how long that would last . The small 12 VDC power supply is prob the best idea. Oh well lots of fun experimenting!

          • It would probably last a while, but it depends on the milliAmp-hour capacity of the battery and the current draw of the memory wire. If you know both you can calculate the approximate number of hours you’ll get from it.

            Yep, there’s probably some other options out there as well if you’re creative. :)

          • Hello Marty I ended up using a 9 VDC wall mount power supply that measured about 15 volts no load. I ended up using 3 diodes in series to reduce the voltage to about 12 .5 VDC
            works great now! As far as the 9 volt battery goes , that works too . but I think i would end up going through one every couple of weeks.

  6. Hi I have a question can you actually do this for me, and ship it to me, and if so how much would it cost to do a Sony car stereo and speakers?

    • Hi Anthony. I’m sorry I can’t as I’m currently traveling. But I’d be happy to try and help you if you don’t understand something.

      Honestly, it’s not very difficult. Especially for just a car stereo and speakers. You just need a decent power supply, some basic wiring connections, and that’s most of it. For battery-backed power (memory wire) support to keep the radio’s settings, it’s just a little bit more and not too hard either.

      Feel free to reach out directly via my Contact page if you need to. Best regards.

  7. Hi Marty,

    Very helpful article – Kudos :) I am attempting to build a very similar setup and have been looking into the 5V SB always on line as a way to allow the PSU to essentially sleep with the fans off but still provide enough power to hold the memory so it doesnt require setting up from scratch, this 5v line remains active even when the PSU is powered on so I am a bit nervous about blowing something up if both are sending power at the same time! I believe the stereo should only draw what it needs but I am a complete novice with electronics, any ideas if this could work and if so how best to wire everything?

    • Hi Jon. Yes it should be possible to do this with a few more parts. The main issue is that the 5V line is too low of a voltage for the memory electronics in the car stereo. So one solution would be:

      – Use a miniature 5V to 12V step-up converter (these are available on eBay and hobby electronics stores online), with the milliamp capacity needed, but should be ~25-50mA or so. Car stereos don’t normally draw much at all for memory.
      – You will need to tie that output and the main +12V supply both to the BATT wire on the car stereo using diodes. This will prevent the +12V output from the power supply, when switched on, from backfeeding to the other wire.

      That would be some standard diodes with the anode site (striped end) connected to the memory wire on the radio. That should do the trick. The PSU should be able to supply the milliamperes needed via the standby wire. (It might need a load resistor connected if you’re not getting 5V as expected, FYI)

      • Thanks Marty! thats very helpful indeed and a way quicker response than I expected too :)
        I would totally have blown my power supply up as I hadnt considered feedback at all!! Diodes I do have but I guess its time to google the step-up converter as I doubt I will find any of those lying around ;-)
        I will let you know if I do get it working as setting it up every time or leaving the PSU on 24/7 both sound unappealing.

        • Sounds good, Jon. Alternatively, you could similarly use a very small AC-DC 12V adapter and connected it via a diode to the memory wire, especially since those may be easier to find and cheap too. Best regards.

          • So I gave it a try with what I had (just the diodes) and it did actually manage to retain the memory over a short period of time, (could the 5V be enough for the memory on my head unit?) This was the second test however, on the first attempt the unit appeared to power on but did not fully initialise and would not respond, I am concerned about this meaning there are too many volts / amps hitting the unit (does the 12V + 5V = 17 V total??). However I was in a dodgy wiring situation also so re-wired and second test worked sweet as a nut retaining memory inbetween powering the head unit fully :)
            I am thinking maybe the 12V needs a resistor or something to reduce the voltage to play it safe as the 5V is ALWAYS going to be present in this config. Any thoughts?

          • Hi, I don’t recommend using on 5V, but if that works that’s good. It’s actually less that 5V at the memory wire as there’s about .6V lost across the diode as well.

            The voltage at the radio would be whatever is the highest supplied (12V at the most etc). You won’t need a resistor for the 12V supply. In fact that’s worse as you’ll lose voltage across it and “starve” the radio for current somewhat.

            The voltages don’t add together like that – they’re either/or when diodes are used & in parallel to a single wire. As long as the diodes are wired correctly it should be fine. But the 4.3V or so that will be present is up to chance if it works or not. (Hopefully that works out)

  8. Thanks for your great advice Marty,
    I have a remote off the grid fishing camp with some 12v solar powered battery power available. So I could easily power the car radio based receiver I am building. I am a novice In building electrical equipment and wonder if I can add an available computer power supply so I can run the radio also on 110v when the generator is going.
    How would a circuit like this be to avoid back feeding or any possible other problems .
    Thanks for any input leading me down the right path
    Also does the wood box I am building needs vent holes for the speakers to work properly or for cooling?

    • Hi, you don’t need vent holes for the speakers so don’t worry over that. Regarding the other topic, you can connect the 12V outputs of both the PC power supply and 12V battery together using diodes.

      You’ll connect the anodes (striped end) together. This will keep the voltage from back feeding and should work fine. You’ll just need to get some that are rated for whatever the radio’s current draw is (should be but a few amps normally).

      Best regards.

  9. Hi Marty,

    Great advice on connecting a typical car stereo head unit!

    I have a vintage push button car radio (the one from the 1950s-70s) and have plans to follow your connection diagram. How can I wire the radio up using a pair of 12v lead acid battery packs and a solar panel?

    • Hello Brian. You can wire 12V batteries in parallel if you like, but the solar panel is more complicated and it would need to be a sufficient output in order to do anything useful.

      For the battery & charging topic, you should be able to find some solar panel / 12V battery guides online. That’s a bit more technical than I can go into here. Best regards.

  10. If I use a PC power supply or ATX, Will this still work if the car audio unit is calling for 11-15 volts negative ground? I just don’t understand the negative ground part

    • Hi, it’s the same thing. Negative ground is what both the ATX supply and most vehicles use. Negative ground means the chassis & metal sections etc. are connected to the negative supply side.

      (Positive ground is extremely rare and not something you’d run across, although we always make sure to be careful when connecting supply wiring to avoid reverse polarity damage).

  11. I have car stereo, signal processor and a 6x50W amp. I am planning to power it with a 50 amp 12V power supply. Should I use a power wire distributor to split the power into 3? 1 for car stereo, 1 for signal processor and 1 for amp? or do you recommend getting different power supplies?

    • Hi the single power supply will be fine for active power but you’ll need a way to keep the memory backup wires live when the main supply is off. For that you could use a very small 12V AC-DC supply with an output of say 1-1.5A or so (or somewhere around that).

      You’ll need to wire it to the memory wires of the car stereo and signal processor with diodes to prevent back feeding from the main supply. That’ll do the trick. Best regards.

  12. Hi marty,
    I have a car radio wired for a garage radio but it won’t take radio code. When I enter number and press 5 it resets radio but if I enter wrong code it goes on to second attempt is it a wiring problem any help would be appreciated.

    • Hi Matt what you’re describing shouldn’t be able to be a wiring problem as long as you have the memory/battery wire powered. That’s an issue with how the code is entered or the code itself.

      If you can get the code entered correctly you could keep the memory wire alive when it’s not in use with a small AC-DC adapter so you don’t have to enter it every time. Best regards.

  13. Great article. I am trying to connect a BOSS marine stereo and tested with the 12V 5A power supply below. It seemed to work but I wanted to check with BOSS. They recommended something much bigger at 14A listed below. Another person recommended a 12V 200W LED driver listed below. Am I good with leaving the 12V 5A I have tested or do I need something bigger to make sure the speakers work well?

    BOSS Stereo:

    12V 5A Power Supply:

    Boss recommendation:

    12V 200W LED Driver:

    • Hi, according to the owner’s manual it has a max. current draw of 15A so you’ll want the larger power supply (or another with a 15A or higher rating.)

  14. hi i have a 80*4 oums power amplifier 9000.4w witch power supply can i use my amplifier keeps on tripping when i turn it loud im playing with two 6500w subs and a 560w power supply

    • Hi, it sounds like your power supply can’t provide enough current. Use the fuse(s) on the amp as an approximate guide for how much current you’ll need and look for a supply with close to that rating if possible.


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