What CC knows about stock Jeep radios

[NickyV]

I'm deep in a phase of radio experimentation. A few weekends ago, I hooked up an AR-series radio (the radio-only kind with the sliding faders), and I hooked up an RCA channel selector out of sight, so I can switch easily between the radio and bluetooth.

 

But I thought I could do better. Today, I found an RX-171 at the JY, and I follwed the video posted by @Pete M to perform one of @Minuit's "Science Projects." It is very easy to do. Per the video, I disconnected the AM band as well, and even repurposed an RCA cord I had lying around to hook up my bluetooth module to the radio.

 

I'm going to drive around with it for a while, but I don't know if I will keep the set-up.

 

The Pros:

 

I really like the fact that I can control the volume of streaming media with the built-in radio knob, and adjust bass and treble and the signal from the bluetooth sounds great.

 

The Cons:

 

The reception on the radio is a bit fuzzy. I don't know if that is unique to the one I grabbed or not. Maybe it could be improved somehow by boosting the signal coming in from the antenna?

 

Now that I have the confidence to repurpose RCA cables and tear apart radios, I am considering trying to do the same process with the the radio-only AR I have by tapping into the appropriate cables above the treble slider.

 

The one thing I'm a bit wary about is that the two cables Minuit identified are from a slightly different model AR than I have. Has anyone tried the hack he described on page 3? Did it work? Also... it sounds like it will work a bit differently than the RX hack, in that it might not override the radio signal.

 

Maybe a simple A/B switch mounted on the dash would do the trick. Or I could just use the RCA channel selector I already have hooked up. Hmm...

 

If I succeed in this next science project, I may offer up the other radio with aux in the classified.

[NickyV]

 

I’m following up on my last post from almost a year ago. I tried to mod the AR series radio I have. My goal  was to make it so ny Bluetooth receiver would go through the radio’s internal volume and dynamics controls. It did not work.

 

I’m not sure which AR I have, but it resembles the AR-7750. I tried tapping into the two wires that Minuit identified on the treble slider. It did not work as I hoped and had to re-solder those two connections back together :-/

 

I set up a simple A/B switch to toggle between Bluetooth and radio and that has been working fine

[A-man930]

On 10/6/2025 at 12:15 PM, NickyV said:

I set up a simple A/B switch to toggle between Bluetooth and radio and that has been working fine

Can you share a picture of this?

[NickyV]

Hey @A-man930 - Attaching a picture. Sorry, It's not the greatest.

 

I might have undersold it when I said "simple A/B switch." Last year when I did this project, I had an RCA switch that I was no longer using. It was actually a five-way stereo switch that I previously used for my home stereo system.

 

The switch has a rotary dial. I mounted it facing down, underneath the steering wheel on the bottom most panel. To use it, I reach under the wheel (below where that vent is between the driver's legs) and turn the knob to select between the two inputs. The other three stereo inputs are not used.

 

On the left hand side are the RCA inputs from the radio and the Bluetooth receiver. On the right are the RCA outputs that run down along the driver side door and back to the amplifiers.

 

 

I am planning to change this setup soon (maybe this weekend). It works fine, but it's a bit over-engineered.

 

My plan is to install a simpler A/B switch and an inline volume knob. I think I will mount it in the space under the clock. Pics below. If you don't have the computer display that monitors engine performance (and I think most of us don't have that), there should be plenty of space underneath the clock to cleanly mount both of these components.

 

Just in case you need more info on how to make this work, here are some other components you need:

 

- Line Level Converter: You need one of these to turn the stock radio outputs into RCA (line level) outputs.

- Various RCA cables of appropriate length

- Bluetooth Receiver.

 

Here are the components I plan to install to simplify my setup a bit. I'm going to install the inline volume knob so I can control volume from the dash, rather than using my phone's volume buttons.

 

 

[holoceneghost]

I just bought a radio model no. 56007214 and everything works... Expect the AM/FM receiver. The antenna on my car is good, and nothing inside the radio looks wrong. Are there schematics anywhere I could look at to troubleshoot this/any common issues? 

@Minuit

Thanks

[NickyV]

@holoceneghost Apologies if I'm explaining things you already know, but...

 

I've done a fair amount of tinkering with a number of these radios. Not as much as @Minuit, but a lot. One thing I can say is that I've made some simple mistakes in the past.

 

One example of a mistake was only connecting power and speakers. I thought that would be enough to get the radio to work, but on some of these radios you must connect the antenna to even get it to power on properly. Sounds like you are past this step, but it's just an example. Connect everything!

 

Another tip is to invest in a bench power supply and some cheap speakers plus all the appropriate connections. Troubleshooting on the bench is WAY easier. Trying to figure out issues inside the cab with the radio in the dash is no fun.

 

Finding manuals for these radios is hard, in my experience. You might be able to find one on e-Bay. But you can also try the Internet Archive. They have a very large database of manuals. Searching it takes patience and isn't super intuitive. I just took a look and I was only able to find one manual. It was not the radio you have. But yours is on there!

 

If you happen to make a breakthrough in how to find our radio manuals, please let us all know!

[holoceneghost]

1 hour ago, NickyV said:

@holoceneghost Apologies if I'm explaining things you already know, but...

 

I've done a fair amount of tinkering with a number of these radios. Not as much as @Minuit, but a lot. One thing I can say is that I've made some simple mistakes in the past.

 

One example of a mistake was only connecting power and speakers. I thought that would be enough to get the radio to work, but on some of these radios you must connect the antenna to even get it to power on properly. Sounds like you are past this step, but it's just an example. Connect everything!

 

Another tip is to invest in a bench power supply and some cheap speakers plus all the appropriate connections. Troubleshooting on the bench is WAY easier. Trying to figure out issues inside the cab with the radio in the dash is no fun.

 

Finding manuals for these radios is hard, in my experience. You might be able to find one on e-Bay. But you can also try the Internet Archive. They have a very large database of manuals. Searching it takes patience and isn't super intuitive. I just took a look and I was only able to find one manual. It was not the radio you have. But yours is on there!

 

If you happen to make a breakthrough in how to find our radio manuals, please let us all know!

 

Appreciate the reply! It doesn't even get signal without the antenna plugged in. I found a website that claims they have schematics for these radios but was double checking here first. 

[holoceneghost]

2 hours ago, holoceneghost said:

 

Appreciate the reply! It doesn't even get signal without the antenna plugged in. I found a website that claims they have schematics for these radios but was double checking here first. 

Not sure what happened, but I fully installed the radio in the car just intending to use the tape deck for now and it slowly started picking up stations. 

[NickyV]

That’s great (hopefully!), @holoceneghost. I have no idea why that would have been the case for you, but back to what I was saying.

 

I’ve made simple mistakes and I’ve also stumbled bass-ackwards into breakthroughs.

 

I forget where it is on the forum, but there is a link somewhere to the “Electrical Troubleshooting Manual” in PDF form. I think I grabbed it from the user with the Taz icon (Tasmanian Devil cartoon).

 

That manual is super helpful.

[MJPIA]

Crossing over from YJ land, I've recently acquired an RX-135 and am very happy with it, it screams like an banshee while ejecting tapes but I don't particularly care about that.

Given this has only two speakers in the dash and I literally bought the cheapest ones I could find I am very pleased with how it sounds

The DNR in areas with poor reception is also baller at cutting static

The KX-135 and KX-137 are identical with the 137 simply having an light up Renault logo instead of the AMC on the cassette flapper, I'm wondering if the service manual for either exists anywhere online, I'm just more thinking for the future given these heavy radios are crammed with circuit boards packed full of 40 year old components and nothing lasts forever so its better to have it on hand that try to hunt things down after something breaks.

 

Secondly I have this sitting around and the hand written number on the top and green tag comes up with nothing on google, I'm mostly curious about it because of the massive sample sticker which makes me wonder what it is and where this could have come from.

Kinda wondering if it was some dealership display where customers could compare the different levels of radio on offer, I dunno

 

Also on a sidenote I have a 74 page dealership 1988 AMC renault manual which lists every accessory they had for everything AMC/Jeep/Renault and breaks down every single radio offered in all their vehicles from 84 to 88 including the part numbers for everything alongside a separate section which lists the 7 Canadian exclusive radios, I could upload those pages if people want them.

Like for example as an oddity 1986 model year lists the AM/FM ETR stereo cassette with DNR in 5 vehicles under 3 different model numbers, Alliance, Encore, both Eagle's and the Comanche but next to the Comanche it notes (Less DNR)

Then for 87 its available for 8 vehicles under 5 different model numbers, none of which correlate to the previous part numbers and the Comanche has DNR while the Wrangler notes (Dolby) next to it

[NickyV]

I would absolutely be interested in learning about all the radios they offered! You should upload that puppy!

[hgeranium]

I would message Minuit personally, but he seems to have been inactive for the past 6 months so I will ask here. In 2022 I installed a Pioneer DEH-S4220BT in place of some old crappy 2004 aftermarket radio. I have zero complaints; it works great. However, a few years ago I pulled a relatively nice RX-173 from an XJ in a pick-n-pull. I love how it looks and I love the idea of being able to play my cassettes in the truck. I know it's gimmicky and bluetooth/streaming will always be convenient, but nothing else about daily driving my truck is convenient so it will make it a little more fun popping tapes in there. I could always swap back if I don't like it as well.

 

For those running stock radios, how is the sound quality compared to a modern unit? I understand it will be worse but how much worse are we talking? Is it worth the look to revert to a stock stereo if it means downgrading in sound? I also just hate the bright blue LED that my new radio has. The old radio that was in there had some terrible compression issues too. Just switching the radios made the audio sound like I swapped the speakers. The sound was way more crisp and waaaay louder. With the old radio, I could barely hear it on the highway at max volume. I'm worried that the RX-173 will bring me back to that but worse considering it's about a decade older than the other unit.

[Gjeep]

The stock units sound hollow as they are not amplified and typically running through stock speakers. Add an amplifier, good speakers, and a sub of any size in an MJ and you'll be cookin'. I love the look of my stock radio with all the modern trimmings. Sounds great

[NickyV]

I second everything GJeep said about adding an amplifier and a sub to your setup. @hgeranium

 

Something I didn’t realize until I got into car audio is that even though many head units do have decent amplifiers built into them, these built-in amps are very small, and are not powerful enough to drive speakers at their full potential. Amps are not just for subwoofers. They are for all the speakers in your system.

 

That means, you will struggle to get your speakers loud enough to be heard while you are driving on the highway. It also means that your signal will get more distorted. (Think of it this way: to get even close to highway volume, you will have to push a tiny amp all the way to its maximum. But if you have a more powerful amp, you will only need to push it maybe a quarter of the way to get to the level you need.)

 

I also want to draw your attention to the end of Minuit’s original post — to the “Science Projects” section. Here is where you will find a write up on how to add an auxiliary input into your RX-series radio.

 

By doing this procedure, you will be able to add an auxiliary input to your head unit. I have done this procedure myself and it is very simple. (It is more complicated on units with tape players, but only slightly. That’s because you have to pull the tape player module out of the way to access the input posts.)

 

If you do this procedure, you will be able to use the head unit’s built-in volume, bass, and treble controls on your aux input. You can make your aux input either a 1/8” input or a Bluetooth module. Then you will have a radio, cassette AND Bluetooth player! And it will look completely stock :)

 

One additional thing to note: If you do this, you will want to either perform the “AM Delete” procedure, or you will want to carry a blank cassette in the truck.

 

I believe most of this is explained in the “Science Projects” section. It is also covered in this YouTube clip:

 

If you have additional questions, feel free to DM me.

[hgeranium]

29 minutes ago, NickyV said:

I second everything GJeep said about adding an amplifier and a sub to your setup. @hgeranium

 

Something I didn’t realize until I got into car audio is that even though many head units do have decent amplifiers built into them, these built-in amps are very small, and are not powerful enough to drive speakers at their full potential. Amps are not just for subwoofers. They are for all the speakers in your system.

 

That means, you will struggle to get your speakers loud enough to be heard while you are driving on the highway. It also means that your signal will get more distorted. (Think of it this way: to get even close to highway volume, you will have to push a tiny amp all the way to its maximum. But if you have a more powerful amp, you will only need to push it maybe a quarter of the way to get to the level you need.)

 

I also want to draw your attention to the end of Minuit’s original post — to the “Science Projects” section. Here is where you will find a write up on how to add an auxiliary input into your RX-series radio.

 

By doing this procedure, you will be able to add an auxiliary input to your head unit. I have done this procedure myself and it is very simple. (It is more complicated on units with tape players, but only slightly. That’s because you have to pull the tape player module out of the way to access the input posts.)

 

If you do this procedure, you will be able to use the head unit’s built-in volume, bass, and treble controls on your aux input. You can make your aux input either a 1/8” input or a Bluetooth module. Then you will have a radio, cassette AND Bluetooth player! And it will look completely stock :)

 

One additional thing to note: If you do this, you will want to either perform the “AM Delete” procedure, or you will want to carry a blank cassette in the truck.

 

I believe most of this is explained in the “Science Projects” section. It is also covered in this YouTube clip:

 

If you have additional questions, feel free to DM me.

This has been invaluable information, thanks so much! Now you have me really excited to have a period correct head unit in the truck again

[hgeranium]

20 hours ago, Gjeep said:

The stock units sound hollow as they are not amplified and typically running through stock speakers. Add an amplifier, good speakers, and a sub of any size in an MJ and you'll be cookin'. I love the look of my stock radio with all the modern trimmings. Sounds great

That makes a lot of sense. I'm sure my new head unit sounds so good because of the amplifier. I'll pick up an amp and give it a try on this 173

[Gjeep]

If you look at my builds I found a good amplifier for the MJ. Nothing crazy. Slippery Slope project probably best. You can see some of the wiring; and the creativity around it. Feel free to DM if questions.

[NickyV]

Happy tinkering! Just go slow and Make sure to take pictures and notes as you go, so you don't lose track of how to reassemble.

[ghetdjc320]

So... I've been digging through a recent RX-172 from a 92 MJ recently. I'm really just doing process of elimination signal testing. I've had many different ideas about what to do with these ready from custom Arduino with OLED interface in place of the stock LCD to installing a DSP amplifier board in place of the tape deck. From what I've been gathering, The main am/fm radio processing board is the large bottom PCB on the bottom of the radio. There is a 3 wire JST connection that feeds the pre-amp module with radio signal in basically an XLR audio format. There is another 3 wire JST from the cassette deck module to the pre-amp. What I'm referring to as the pre-amp is the small board that hosts the two pins that people are using for the aux input and the volume/fader and tone control pots. The actual amplifier board is located just behind the main radio speaker/power connector. I'm going to do a picture dump so everyone can see the insides in more detail. 

 

I have zero use for the tape deck. with the removal of the tape mechanism bracket, you now have a really nice mounting platform for a variety of PCB modules such as DSP's or Amplifiers. The radio board still needs power to provide the LCD with information to display such as the clock and radio station. Will add to this in a bit but for now here is a picture dump:

 

[watchamakalit]

5 hours ago, ghetdjc320 said:

So... I've been digging through a recent RX-172 from a 92 MJ recently. I'm really just doing process of elimination signal testing. I've had many different ideas about what to do with these ready from custom Arduino with OLED interface in place of the stock LCD to installing a DSP amplifier board in place of the tape deck. From what I've been gathering, The main am/fm radio processing board is the large bottom PCB on the bottom of the radio. There is a 3 wire JST connection that feeds the pre-amp module with radio signal in basically an XLR audio format. There is another 3 wire JST from the cassette deck module to the pre-amp. What I'm referring to as the pre-amp is the small board that hosts the two pins that people are using for the aux input and the volume/fader and tone control pots. The actual amplifier board is located just behind the main radio speaker/power connector. I'm going to do a picture dump so everyone can see the insides in more detail. 

 

I have zero use for the tape deck. with the removal of the tape mechanism bracket, you now have a really nice mounting platform for a variety of PCB modules such as DSP's or Amplifiers. The radio board still needs power to provide the LCD with information to display such as the clock and radio station. Will add to this in a bit but for now here is a picture dump:

 

[ghetdjc320]

3 hours ago, watchamakalit said:

Pics added 

[ghetdjc320]

Next up, I’m going to measure the am/fm radio module output voltage to the pre-amp. I’d like to install a tinysine Bluetooth module which has an audio priority line. So basically, the am/fm radio signal will first go to the tinysine module. The module will pass through the audio from the radio until it receives a Bluetooth audio signal. Once it does, it will completely block the am/fm input. This is in an effort to delete bleed through from the radio without disabling it. 
 

The issue we’ve had with this in the past is the output level of the tinysine module is 1.9vrms which overloads the pre-amp and introduces distortion. So I will introduce a line level attenuator to the signal to match that of the am/fm radio. 
 

Then I’ll tap the pre-amp output signal and run it through an active DSP board which will ramp back up my line level outputs from .6vrms up to +/-2vrms. 
 

Replacing the bulbs on the RX-172 LCD is tricky but not difficult if you take your time and don’t overheat the board desoldering the bulbs. 
 

The replacement bulbs for the actual button backlighting is a t1 style. I’ll post up part numbers here in a bit. Too much of this information has stayed elusive now for too long imo. 
 

Another option I’m exploring is repurposing the play/rewind/fast forward buttons to control the Bluetooth module playback. I’d map them as play/pause, skip forward and return. I’d also like to map an actual input switch. If I go this route, the priority audio pass through will be irrelevant. The ultimate goal here is keeping it looking stock but functioning like a newer unit and integrating a DSP for audio quality improvements.

[NickyV]

This is extremely exciting. Can't wait to hear more about this!

 

I've been poking around inside an extra RX-model that I have, but it sounds like you know a lot more about this than I do.

 

I totally understand that the tape player will be useless to many, but I like the idea of being able to play tapes. But to each their own!

 

All-in-all, it would be SO awesome, if you (or anyone) could figure out how to get the LCD (or a replacement LCD) to display custom information -- even if it just said something simple like "AUX."
 

[eaglescout526]

I have split the radio knowledge to a new thread. It’s titled under what we as CC know about the radios while keeping the integrity and legacy of Minuit separate from what we figure out collectively. 

[ghetdjc320]

1 hour ago, NickyV said:

This is extremely exciting. Can't wait to hear more about this!

 

I've been poking around inside an extra RX-model that I have, but it sounds like you know a lot more about this than I do.

 

I totally understand that the tape player will be useless to many, but I like the idea of being able to play tapes. But to each their own!

 

All-in-all, it would be SO awesome, if you (or anyone) could figure out how to get the LCD (or a replacement LCD) to display custom information -- even if it just said something simple like "AUX."
 

I've been considering that option as well. You could run a raspberry pi based system and an old or lcd display. Would be fairly straight forward to have it display metadata like bluetooth song info, radio station numbers/names (with an HD radio hat) and input names. If I was going that route (which I may lol), I'd just strip the entire guts out of the radio and use the shell, faceplate and probably the buttons interface once I've mapped them out.