[Childs Play]

I’ve put together a guide for wiring an amplifier into a USA Spec Hyundai Ioniq Hybrid without the premium Infinity sound system.

I’ve seen a few people asking how to do this since there’s no traditional 12V lead-acid battery in these cars so I put together a guide for whoever may need it.

Disclaimer: I am not responsible for your vehicle or you if you mess something up. This guide is to help people who have a moderate understanding of vehicle electrical/stereo systems and need a little extra help in figuring out this rather complicated vehicle.

Also, please be aware that you are working with electrical components. Do not move forward with this guide unless you have a moderate understanding of how to install car stereo equipment, or do not feel comfortable doing this. While a shock from a 12V system can be a bit painful and scare you, a shock from the 240V system can and will kill you. If you’re following this guide you won’t be messing with any wiring that has to do with the 240V system. But if you don’t know what you’re doing and disconnect or dig into something you shouldn’t, you might.


Things Needed:

Amplifier (I’m using the Rockford Fosgate PBR300X1 for this guide.)

Amp install kit (Depending on amp and subs this can vary. I used the Rockford Fosgate RFK10 kit for this install.)

Speaker Wire (I purchased 16 Gauge, but it may be easier if you use something smaller to get through the door, however 16 Gauge is what is recommended for the amp speaker connections on the amp I’m installing.)

Rockford Fosgate RFI2SW Speaker Line to Male RCA Adapter (If installing as High Level input to same amp used in this guide.)

Remote Punch EQ (PEQ) – Optional

Socket wrench

10mm socket

12mm socket

Philips head screw driver

Coat hanger

Flash light

Wire stripper/cutter

Quick connects or soldering iron

Needle nose pliers


Power Wire Install

First thing you’ll want to do is pop the hood. You’ll then want to unbolt the box in the below picture with the 10mm socket. It has three connection points, one up top and two at the bottom. You may need some extensions to get to the two bottom ones. Also, go ahead and remove the mat and tire inflation kit from your trunk area so you have more room to work with once you get to that step.

Once you have it unbolted you can lift it up a bit and pull it towards the front and center of the car. You’ll need to do this unless you have small hands and can get behind this with no issues, or if you can get a hold of the coat hanger without doing this step.

Back inside the car under the dash near the emergency break there is a rubber grommet which you’ll need to push/pull through to have an access point through the firewall. I had a screwdriver going through the firewall in the photo so I could identify where it came out on the engine bay side.

*It’s worth noting here that this worked with a 10 gauge wire. I’m using a PBR300X1 amp from Rockford Fosgate as it is a highly efficient amp designed to be used on Motorcycles and ATVs. Given that this electrical system is supposedly pretty limited due to not having a traditional 12V battery, I went this route. You may be able to get away with a slightly larger wire with a different amp. I did not test this however.*

You’ll want to then push a coat hanger through the firewall hole where you moved the grommet from the interior to the engine bay.

Once you have that, you can tape the power wire to it to pull it from the engine bay through the firewall to the interior. While it will involve pulling almost all of the wire through, you need to do it this way if you have an inline fuse already pre-installed into the wire as you will not be able to push the fuse part of the wire through the driver’s area to the engine compartment.

Once you’ve pulled it through the firewall you’ll want to carefully thread all of the wire through (like above) up till you have just enough under the hood to route it and connect it to a connection under the fuse box. Do not hook the power wire up just yet. You can go ahead and bolt the box back on you unbolted earlier.

You’ll then want to route the wire under the trim (as demonstrated in the above right photo) to the back of the car starting by pulling all of the wire back behind the emergency break and hood release working your way to the back seats. The middle trim on the front door is removable by lifting straight up on the ends and then middle. However, it isn’t 100% necessary to remove the trim to route the wire.

Then you’ll want to run it under the trim up to and under the seat as shown below. You may need two people to push the wire under the seat to the hatch/trunk area as shown. I had a friend help me do this but you can do it yourself if necessary. It will just take some extra time.

You’ve now successfully routed the power wire.

*If you’re ready to wire the power wire to the car you can follow the below step, if not, skip to the ground wire section and come back to this later.*

Make sure to remove the in-line fuse before doing this step. To hook the power wire to the car’s electrical system you’ll need to unbolt the connection with a 10mm socket, install the wire, and reinstall the nut as shown. You can then run the power wire down the side of the box along the side of the other wire running down the side of the box, and reinstall the cover.

 

[Childs Play]

Ground Wire Install

Now you will want to install the ground wire. I just undid the bolt shown below for back seat with a 12mm socket, put the wire with its connector around the bolt, and bolted it back down. There are other places you could install the ground, but this was the easiest place I found.

 

[Childs Play]

REM Wire Install

Run the remote turn on wire the same way you ran the power wire, however start from the back of the car and work your way forward. Then come back up through the fuse box section under the driver’s side dash. I installed the REM wire into the fuse shown (It's labled "Washer" on the fuse guide; Blue wire in picture.) as it turns on the amp when the car starts and turns off the amp when you turn the car off. This will keep your amp from running the battery down when the car is not in use. There are other fuse connections that turn on and off with the car as well. Just watch which one you hook it up to as some of the fuse connections are on constantly whether the car is on or off. If you hook it to one of these it will leave the amp on and drain your battery.

 

[Childs Play]

Speaker Wire Install

First, you’ll want to remove the door panels. There’s a video on YouTube for how to do this. Just search for “how to remove door trim Hyundai Ioniq” and a video by Paul Romo (not me) should show up. The easiest way to do this is to first, remove the screw under the rubber piece sitting down in the arm rest. You will then start at the bottom of the door (there’s a gap to make it easier for removal there) and pop the door trim out working your way left and right. Once you have all the clips undone, you can lift upward.

You’ll need to remove two connections at this point to fully remove the door. The electrical connection for the window and the connection for the door handle itself. The electrical connection has one clip. Push that in and pull it out. The door connection also has one clip. You’ll lift that clip and then tilt it up/away from the door and it will unhook. This is all explained in detail with the video mentioned above.

Then, remove the four bolts holding the speaker in place as you’ll need to access behind it to run the wire from the door to inside the car.

Next, you’ll need to remove the inner B-pillar trim of the car. If you have reinstalled the front seat bottom door trim, or did not remove it while running the power wire at the bottom of the driver’s side door, go ahead and remove it.

Then you’ll want to pull the weather stripping out a bit till you have cleared the dark lower trim on the B-Pillar. This may not be necessary, however I found it easier to remove the inner trim this way.

After that, you’ll want to pull the seat all the way forward as well as tilt the back support all the way forward.
Starting from the bottom to remove the B-pillar trim, pull directly away from the trim to remove it. To make this easier, you can push the seat belt connection at the bottom, flat. You can look under to see where some of the clips are so you don’t damage the trim by bending it. Once you’re near the top, the trim is clipped into the top lighter section on the sides. You can reach under and pull up on each side. It will un-clip. Then there’s one more clip that you’ll need to pull out, away from the pillar to release the trim. See the below picture for what the area looks like with the trim removed.

Once you have the trim removed, I’d recommend moving the seat belt out of the way as shown above. I just pulled it out all the way and then wrapped it around the seat and under the headrest. This will give you room once you get to pulling the wire through.

Next, you’ll want to remove the bottom rubber grommet shown in the picture below at the bottom of the exterior B-Pillar as well as pull back/undo the rubber boot from the door and car pillar. With this grommet removed and the inside trim of the B-pillar removed, you’ll be able to see through the small hole through the car. This is where you’ll eventually pull the speaker wire through.

**Note: If you plan on hooking up to your amp with a high level speaker input connection, you’ll only need to run a positive wire from the positive connection on your speaker to the rear area to connect to the amp. If you want to install a high to low converter you’ll need both the positive and negative speaker wires ran from the speaker to the amp.**

You’ll want to run the wire behind the speaker inside the door and through the rubber boot. I just pushed on the wire till I managed to get it through. Don’t force it. If you’re stuck, start over. Once you have the wire through the rubber boot, you’ll then want to pull enough through to where you’ll be able to wire it under the inside trim and under the seat to the trunk/hatch area.

Once you have enough wire through the rubber boot, you’ll want to un-clip the connector shown in the picture below and pull it a little inward. You will not be pulling the wire through this hole; this is just giving you more room to use the coat hanger down a slight gap to the hole below where we removed the rubber grommet earlier.

Grab the hanger again and tape the end of the wire to it. Making sure it’s flat as possible. You’re going to start from the top and push it down through a small gap in the wall of the car. Keep pushing it till you can see the wire/hangar as shown in the pictures above.

Once you can see the wire, you can go from the inside of the car with the needle nose pliers to pull the wire through the hole directly behind the hole shown circled in the below picture. It’s a tight fit, but you can get to the small hole where the grommet was from the opening at the bottom where the seat belt is mounted as you can see through the car at this point with the grommet and inner trim removed. Pull the wire through. You will most likely damage the end of the wire doing this. That’s fine. Once it’s all pulled through, cut the end off past the point of damage.

Now just run the wire along the same path that you did for the power and REM wire for both sides. You can see the routing for the speaker wire above and coming out the back below.

You can push the rubber boot for the wires back into the door and pillar. Do this before snapping the wire harness connector back into place as it makes it easier to get the boot back in and sealed.

Snap the connector back into place where you ran the wire down through the door.

You can now install the inside pillar trim back in. Take care to snap it back into place properly. You’ll likely have to pull the back seat trim piece forward to fit the pillar trim back under it. Reinstall the grommet into the door.

 

[Childs Play]

Once you have that done, run the wire back behind the speaker and through the grommet in the door as shown below. I just drilled a hole through the grommet and then pushed the wire through. I also had already re-installed the speaker by the time I took the photo below.

I’d recommend rolling the windows down for this part (You’ll need to hook the door trim plug back up to do this for each door.) to make sure you run the wires properly and they don’t interfere with the windows when they’re rolled down. Also, you'll want to have the wire held in place as I noticed a slight rattle when hitting bumps originally. Once you’re sure you have enough length you can cut the speaker wire you’ve ran though the door. Then strip the end of the speaker wire you installed so it will have a good connection when the quick connects are installed.

Then, take the quick connects and hook the positive and negatives to the speaker wires as shown above. You'll have to pull back a little bit of the wrapping on the speaker wires.

Positive and negative wires for the speakers in the back doors are as follows…

Driver side:
Positive, Yellow.
Negative, Black.

Passenger Side:
Positive, Brown.
Negative, White.

To verify this, you can test it with a C/D battery by hooking up a wire to the positive and negative side of the battery and then touching the speaker. If the speaker pushes out you’ve got the positive and negative connections identified. If the speaker pushes inwards, you are backwards. There are a few YouTube videos on how to do this if you want to try it yourself. This guide is assuming all of the wires will be the same colors across different vehicles, but you shouldn't. I recommend you double checking.

Once you have the wire connected you can do the same test as mentioned above at the end of the wires in your trunk/hatch area to make sure you have a good connection to the speaker.

You can now reinstall the door trim. Make sure to hook up both the electrical connector and door handle connection before putting it back on or you’ll have to take it back off. Once all the clips are back into place reinstall the screw in the armrest and put the rubber cover back in.

 

[Childs Play]

Amp Wire Connection Install

Your amp is now ready to be wired. For the amp I’m using, the connector can be removed which makes hooking up all the wires extremely easy.

The power wire will be hooked to the “B+” connection. The ground wire will hook up to the "G" connection. And finally the remote on REM wire will be installed to the "REM" connection. Take care not to have any short due to a cable strand sticking out and possibly touching one of the other wires. The amp is now wired.

 

[Childs Play]

Amp Speaker Input Wire Connection Install

For the amp I’m using, there are two different ways to install the speaking inputs. You can either do a high level wire install (This is directly taking the wires ran from the car speakers and running them to the amp inputs) or a low level install which involves buying a high to low converter box separately as well as an extra RCA male to male cable to run from that box to the amp. Both will work for the amp I’m installing, you just have to have the right setting pushed on this amp.

Not all amps can do both high and low inputs. Check your amp before installing to know what type of connection you’ll need.

For ease of install and to save money, I am installing as a high level input. For this I purchased the Rockford Fosgate RFI2SW Speaker Line to Male RCA Adapter. I also realize I took no pictures of this however if you follow the instructions for this on Rockford Fosgate's website you will be fine. Scan from the booklet I had is below. Note that it says the grounds go back to the source unit to be grounded there. You can ground to the frame and it will work just as well.

For High Level Input to Amp using the RCA adapter:
Connect the Left Side Positive speaker wire to the White wire on the RCA adapter.
Connect the Right Side Positive speaker wire to the Grey wire on the RCA adapter.
Connect a separate speaker wire that will be hooked to a ground to the White/Black wire on the RCA adapter.
Connect a separate speaker wire that will be hooked to a ground to the Grey/Black wire on the RCA adapter.
Connect both of the negative speaker wires to a ground on the car. You can use the other bolt on the seat to do this next to where you hooked up the ground. (Further up near the beginning of this guide.)

(IF YOU RAN BOTH POSITIVE AND NEGATIVE SPEAKER WIRE FROM THE SPEAKERS, DO NOT HOOK UP THE NEGATIVE SPEAKER WIRE TO THE NEGATIVE RCA ADAPTER CONNECTION FOR A HIGH LEVEL AMP CONNECTION. YOU CAN/WILL CAUSE DAMAGE TO THE AMP AND/OR THE CAR STEREO SYSTEM.)

 

[Childs Play]

Remote Bass Boost Install

For this optional remote connection you’ll need to start at the front of the passenger side of the car. Clean out your glove-box and remove the two grommets as shown. This will allow the glove-box to fall lower so you have access behind it.

Go from underneath the passenger side dash and push the wire up through the bottom till you can pull it into the glove-box area. I pulled enough through and then pushed it through the hole where the grommet was to hold it snug for the install.

You’ll then want to run the wire back behind the kick panel, then under the trim, behind the seat belt to the back seat. You’ll then want to run it under the trim and the seat to pull it through to the trunk/hatch area the same way previous wires were ran and pulled through above.

You can then connect it to the amp. Reinstall the grommets in the glove-box and put everything else back in it. You’re done.

That completes the wiring guide for the amplifier and speaker inputs on the USA spec Hyundai Ioniq Hybrid. I will not go into detail about how to wire the amp to the sub-woofers as there are different ways to wire them depending on your setup and if you want to wire them to 1Ω, 2Ω, or 4Ω as well as in parallel or in series. You should follow the directions provided with the equipment. depending on what type of subs and amp you have, they can/will be wired differently.

There may be some better ways to run some of the wires and there also may be a better way to hook into the speakers. I however did it the one way I found that worked.

Hopefully this guide can help a few other people who want a bass system in a car that is a bit different than a normal car. If you have any questions or need some clarifications please reply in this thread and I will try to get back with you. I know I'm a bit A.D.D. when it comes to these things so I may have not made something as clear as I needed.

 

[ScorpioH]

Great write up and thanks for finding an efficient amp! Luckily my PHEV has a 12v in the trunk area saving my from having to go through the firewall. I'm curious, where did you windup placing your amp?

 

[Childs Play]

Great write up and thanks for finding an efficient amp! Luckily my PHEV has a 12v in the trunk area saving my from having to go through the firewall. I'm curious, where did you windup placing your amp?

Thanks. I ended up mounting it directly on the box I built. Since the amp can be completely unplugged with two connections really quickly I opted for that so I could completely remove everything from my car in a couple of seconds.

My original plan was to design a fiberglass box that would directly install in the driver’s side hatch area and carpet that where the trim originally was so you wouldn’t even be able to tell it was there. But when I realized I could just remove the whole thing with that amp anyway, I went with the box.

That way I could remove the system entirely if I was going to need the room or have my car sitting at the airport for an extended amount of time.

I’ll get some pictures of the box and everything else tonight after work as I have to pull it out anyway.

 

[evioniq]

Hey is it possible to put some sound deadening behind the speaker, well behind meaning on the inside part of the door panel itself?

Is it easy to remove the whole black door shell that holds everything in place? Or would it be easier just to remove the speaker and put some back there though it might be tight with room?

Speaker Wire Install

First, you’ll want to remove the door panels. There’s a video on YouTube for how to do this. Just search for “how to remove door trim Hyundai Ioniq” and a video by Paul Romo (not me) should show up. The easiest way to do this is to first, remove the screw under the rubber piece sitting down in the arm rest. You will then start at the bottom of the door (there’s a gap to make it easier for removal there) and pop the door trim out working your way left and right. Once you have all the clips undone, you can lift upward.

You’ll need to remove two connections at this point to fully remove the door. The electrical connection for the window and the connection for the door handle itself. The electrical connection has one clip. Push that in and pull it out. The door connection also has one clip. You’ll lift that clip and then tilt it up/away from the door and it will unhook. This is all explained in detail with the video mentioned above.

Then, remove the four bolts holding the speaker in place as you’ll need to access behind it to run the wire from the door to inside the car.

Next, you’ll need to remove the inner B-pillar trim of the car. If you have reinstalled the front seat bottom door trim, or did not remove it while running the power wire at the bottom of the driver’s side door, go ahead and remove it.

Then you’ll want to pull the weather stripping out a bit till you have cleared the dark lower trim on the B-Pillar. This may not be necessary, however I found it easier to remove the inner trim this way.

After that, you’ll want to pull the seat all the way forward as well as tilt the back support all the way forward.
Starting from the bottom to remove the B-pillar trim, pull directly away from the trim to remove it. To make this easier, you can push the seat belt connection at the bottom, flat. You can look under to see where some of the clips are so you don’t damage the trim by bending it. Once you’re near the top, the trim is clipped into the top lighter section on the sides. You can reach under and pull up on each side. It will un-clip. Then there’s one more clip that you’ll need to pull out, away from the pillar to release the trim. See the below picture for what the area looks like with the trim removed.

Once you have the trim removed, I’d recommend moving the seat belt out of the way as shown above. I just pulled it out all the way and then wrapped it around the seat and under the headrest. This will give you room once you get to pulling the wire through.

Next, you’ll want to remove the bottom rubber grommet shown in the picture below at the bottom of the exterior B-Pillar as well as pull back/undo the rubber boot from the door and car pillar. With this grommet removed and the inside trim of the B-pillar removed, you’ll be able to see through the small hole through the car. This is where you’ll eventually pull the speaker wire through.


**Note: If you plan on hooking up to your amp with a high level speaker input connection, you’ll only need to run a positive wire from the positive connection on your speaker to the rear area to connect to the amp. If you want to install a high to low converter you’ll need both the positive and negative speaker wires ran from the speaker to the amp.**

You’ll want to run the wire behind the speaker inside the door and through the rubber boot. I just pushed on the wire till I managed to get it through. Don’t force it. If you’re stuck, start over. Once you have the wire through the rubber boot, you’ll then want to pull enough through to where you’ll be able to wire it under the inside trim and under the seat to the trunk/hatch area.


Once you have enough wire through the rubber boot, you’ll want to un-clip the connector shown in the picture below and pull it a little inward. You will not be pulling the wire through this hole; this is just giving you more room to use the coat hanger down a slight gap to the hole below where we removed the rubber grommet earlier.


Grab the hanger again and tape the end of the wire to it. Making sure it’s flat as possible. You’re going to start from the top and push it down through a small gap in the wall of the car. Keep pushing it till you can see the wire/hangar as shown in the pictures above.

Once you can see the wire, you can go from the inside of the car with the needle nose pliers to pull the wire through the hole directly behind the hole shown circled in the below picture. It’s a tight fit, but you can get to the small hole where the grommet was from the opening at the bottom where the seat belt is mounted as you can see through the car at this point with the grommet and inner trim removed. Pull the wire through. You will most likely damage the end of the wire doing this. That’s fine. Once it’s all pulled through, cut the end off past the point of damage.


Now just run the wire along the same path that you did for the power and REM wire for both sides. You can see the routing for the speaker wire above and coming out the back below.


You can push the rubber boot for the wires back into the door and pillar. Do this before snapping the wire harness connector back into place as it makes it easier to get the boot back in and sealed.

Snap the connector back into place where you ran the wire down through the door.

You can now install the inside pillar trim back in. Take care to snap it back into place properly. You’ll likely have to pull the back seat trim piece forward to fit the pillar trim back under it. Reinstall the grommet into the door.

 

[ScorpioH]

Hey is it possible to put some sound deadening behind the speaker, well behind meaning on the inside part of the door panel itself?

Is it easy to remove the whole black door shell that holds everything in place? Or would it be easier just to remove the speaker and put some back there though it might be tight with room?

Yeah I was wondering this too! It looks like it would be a pain but doable. My old car had some plastic sheeting that was glued onto the door that was a pain to deal with and not really salvageable once removed. The pictures make it seem like it's a plastic/rubber held in w/some bolts.

 

[Childs Play]

Hey is it possible to put some sound deadening behind the speaker, well behind meaning on the inside part of the door panel itself?

Is it easy to remove the whole black door shell that holds everything in place? Or would it be easier just to remove the speaker and put some back there though it might be tight with room?

I didn’t attempt this so unfortunately I’m not sure of the answer. ? Next time I have the door panel off I’ll see what I can find out. However, you should be able to get in there a bit if you had to go through the speaker hole when it’s removed.

 

[Childs Play]

Great write up and thanks for finding an efficient amp! Luckily my PHEV has a 12v in the trunk area saving my from having to go through the firewall. I'm curious, where did you windup placing your amp?

I originally had my amp mounted dead center of the back of the box.

However that amp (was used) had an issue due to the guy who sold it to me not being 100% truthful. I bought a new one and mounted it up near the top of the box so it was close to the speaker input.

If I did it over I’d put the speaker connects at the back and the amp back to dead center. I just moved it because I didn’t want to add extra wire again coming off the amp connector so I could avoid any extra resistance.

The only issue now is that I can’t push the box all the way up against the seat. I could before the relocation.

The subs are wired in series so I have a single connection coming out of the box.

Here are some pictures.

 

[Childs Play]

Also, when un-clipped and pulled out this is what you see. This can easily be tucked under to the spare wheel area when not in use as long as you make sure to protect the 12V connection from touching metal and shorting.

I’m doing this from my phone, so sorry if the images are too small or messed up.

 

[Childs Play]

Also, something I forgot to mention in my guide.

There is a slight buzz for about the first 3 seconds when you start the car and then it goes away. After I turned the gain down when tuning the amp it was completely unnoticeable.

I've noticed this in other vehicles before as well and it can be common. Some have a buzz and others will have a pop.

I had a 2012 Camaro 2SS that had the premium sound and I had to hook into the factory amp's pre-outs that had the popping sound. That one annoyed me to the point that I bought a trigger delay so it would turn the amp on a few seconds after the car started just to avoid the popping sound.

With this car I don't think it would be necessary though. And it's not going to hurt anything if you don't by a trigger delay.

 

[Childs Play]

Just a three+ month update. The setup is still going strong and I've ran into no issues with the battery, electrical system, or anything else with the way the amplifier system is currently set up. System is easy to remove when needed for extra room in the cargo area.

I did find that I needed to add some sound deadening material to the rear hatch to stop some vibrations where the plastic panels were hitting the metal body. Other than that, after tuning the amp a bit it sounds great. A little bit of base definitely changed the sound in the car since the basic model stereo system had none and was rather weak.

 

[Childs Play]

Just a year+ update. I've had zero issues with this setup. No electrical oddities and the system still sounds good. I may be working on installing a second amp soon here for the main speakers to have a bit better overall sound.

 

[Odie]

Are you aware that if you have any electrical related issues with your Ioniq in general, what you have done is voided your Warranty !

 

[Childs Play]

Are you aware that if you have any electrical related issues with your Ioniq in general, what you have done is voided your Warranty !

Absolutely. However, any modification can do this really.

Also it doesn’t “void” the warranty per say. What it would do is be cause for denial of repair with the warranty.
I’ve installed a lot of stereo equipment over the years and have never had an issue.

I do know that this is a bit different considering that it’s not a normal battery. However everything here is easily removable with exception of the door wiring. But they aren’t going to rip your door panels off to check for something.

Catch cans and intakes can do the same thing. I had a friend who’s Camaro blew the engine and they denied the warranty claim due to having a catch can. He fought it and lost. Got to be careful on every mod you do to any vehicle.

That’s why I say I’m not responsible for your vehicle however.

Every mod is “At your own risk.”