Raspberry Pi Car-puter with touch screen, Apple Carplay, sensors, cameras, etc

@soundman98 Do you think it would be possible to find a stereo system which can directly connect to the JBL amp ? (and would be under $200 ?)

I also looked at this particular stereo system:

$80 for Toyota Camry 2006 2007 2008 2009 2010 2011 Android Car Stereo for Toyota Camry 9" HD Touch Screen Car Radio with Mirror Link, WiFi, GPS Navigation, Bluetooth, FM Radio, USB, Rear View Camera

https://www.amazon.com/Stereo-Android-Multimedia-Navigation-Bluetooth/dp/B086GPWSF8?crid=1T7RZ3N5SB4PM&keywords=10+inch+stereo+toyota+camry+jbl&qid=1673677142&s=electronics&sprefix=10+inch+stereo+toyota+camry+jbl%2Celectronics%2C122&sr=1-4&ufe=app_do%3Aamzn1.fos.f5122f16-c3e8-4386-bf32-63e904010ad0&th=1

In the reviews/questions people have mentioned using a PAC RP4.2-TY11 harness (or sometimes even a CANBUS harness). Do you have idea about this ? How does it differ from the Axdis-TY1?

I also re-read your answer for my first question where you suggest the AXDIS-TY1. Does Raspi aux output not qualify as direct speaker output ? I was able to connect a speaker to aux cable directly and get sound through it, hence the question.

 

that is going to be considered a 'standard' stereo. i don't know if anyone makes a stereo that directly integrates, though i doubt it. joying is one of the brands that leads the way in factory integration, but none of their units are cheap, and i think even the $1000+ tacoma-specific model requires aftermarket gear for integration with the jbl system.

the pac rp4.2-ty11 is going to be identical in function to the axdis-ty1, just a different brand, different cost, same features, though looks a little more refined in doing those same features.

i did find this $70 version, Amazon and metra's documentation claims this is compatible with 2007 camry's with amp. this one doesn't support steering wheel controls(not sure how critical this is-- if there's an arduino library for aftermarket radio control commands of any brand, this could allow steering wheel button integration with the pi, which might be an entirely different rabbit hole).

$70 AXXESS Metra TYTO-01 JBL Amplifier Interface Harness, BLACK

https://www.amazon.com/Metra-TYTO-0...fos.18ed3cb5-28d5-4975-8bc7-93deae8f9840&th=1

this is the 'can-bus harness' i'm finding. it looks to be a direct-connection for a specific radio model that they don't identify.
https://www.aliexpress.us/item/3256...00029745438788!sea&curPageLogUid=M5sqblnXmVGO
no connection information at all, so no idea if it works, how it works, or if it could be adapted to work. i don't like it simply for the lack of info.

from my '1, 2, 3' options list with the amplifier input required, i honestly have no idea what that amplifier requires, i wasn't able to locate that info easily anywhere. the availability of 'magic black boxes' makes this very murky territory. although the availability of the 'can-bus harness' could indicate to me that it's really just option 2, and companies are making a 'black box' to turn a profit in a 1-size-fits-all form factor.

if a canbus harness works, i'm seeing them at less than $20, which would make it worth some hassle. but that's still going to require something that creates speaker level outputs.

was it annoyingly loud with the pi set to full volume? probably "just barely audible, i could talk over it". that would indicate it's a low level audio signal. signals are simple, speakers are simple. most speakers will work connected to a low level audio signal, but will lack clarity and volume. the difference is the voltage of the signal. a speaker level signal is around 10-100volts. a low level audio signal is somewhere between 0.5-3v in most cases.

 

Then, I think the question changes to, is there a way to work on converting low level audio signal to speaker level ?

Thank you for information on the harnesses! I still have to look into the links you provided, but the speaker level signal is not leaving my mind yet.

Also looked into this canbus harness: https://www.ebay.com/itm/394367088007?fits=Year:2007|Model:Camry|Make:Toyota

Not sure if that would be of value here.

 

yep, you need an amplifier.


could be something as simple as this
https://www.ebay.com/itm/275587065612?epid=563149615

or something like a head unit.

a head unit is going to use all the same colors as one of those harnesses. an amplifier is going to require some understanding of the pins/colors used, and will need to be cut up to be made to work. not impossible, but definitely a risk to it.

 

Kinda funny to have to add an amplifier to get the signal to the amplifier. LOL.

Anyway, seems like there needs to be a decision:
Option 1: Buy a head unit, that works with one of the PAC or the AXDIS-TY1 harness.
Advantages: Android Auto/Carplay + Touch Screen + Steering wheel buttons work (most likely). Backup cameras work with direct connections. No need to spend time on building a raspi version of anything. and, $250-300 flat.
Disadvantages: basically cannot make upgrades of any sort.
Very little risk of going wrong or damages.

Option 2: Buy an amplifier, to send speaker level signal to the JBL amp directly.
Advantages: Can add raspi and then touch screens and basically control upgrades.
Disadvantages: Spend days/weeks installing everything on raspi, make all connections by myself. Android Auto/Carplay + Touch Screen + Steering wheel buttons don't work. Anything additional with the setup cannot be added directly and will need more work (and so even the setup needs to be removable). and no idea what the cost of this turns out to be.
Lots of risk of going wrong and damages, with added complexities.

What would you do ? (I don't want to say what I wanna do yet before listening to your thoughts)

 

it really depends on your motivations as i had indicated early on.

when i did a carpc, i enjoyed it. i learned a lot on extremely technical subjects, and there was tons of things to do with it. but life changed, the market changed, and everything that i did with the carpc was suddenly easily accessible with a $400 head unit and a $200 sound processor, that previously required $2-3k in audio hardware, easily justifying a $1k carpc build. i run the head unit/sound processor combo now, and don't regret getting away from nuances of the carpc that in all honesty never worked exactly as i wanted it to, and was always a few steps from being 'perfect'.

for me, the head unit does everything i need and anything beyond, i use my phone with the bluetooth connection to do. between my radio and my phone, i've got am/fm/cd/sd-card/4g/internet radio. all in a simple to use package that doesn't take months to configure.



so it comes down to why you're wanting to use the pi in the first place.

if it's to better learn the pi, to push your personal boundaries in various ways, and/or create a solution to a common problem with an uncommon set of parts, adding the amp to go to the amp is going to be the best option.

if you're only using the pi because it was laying around gathering dust and you originally saw it as the most cost effective option to a simple problem, than the replacement stereo is going to be the better option because it will end up being more cost effective, and simpler to use in the long run.

 

I think I will have this problem as well, where I'm never 100% satisfied with my work.
And thank you for your honesty. I think $200-300 will solve the problem for me too.

Honestly, before you answered, I was kinda fighting between the two.
I feel like I want to work on the pi to build something that I would be proud of, but I'm also tired of not having music and maps during my drives around the city (since I broke my music system like year and a half ago, LOL). And if I go the route of building it, it will take some time to get through it, and I think it will pile up into my don't-feel-like-working-on-this-right-now pile every once in a while and get stuck.
I think for now I'll just get a system that works with least effort.

So, again, thank you for honestly answering!

 

Hello on the thread again.
Thought I'll give an update.

I bought a stereo from Ebay, this one: https://www.ebay.com/itm/234596452192?epid=15054510598

The thing is, I can't get it to work!
The power output from the 16-pin cable in the car is not giving me any reading on the Voltage difference (multi-meter).
So, I tried to re-wire the BAT and GND outputs of the cable (per the image attached) appropriately getting a total of 13-ish Volts into the power for the Stereo. It still doesn't start up.

I'm hoping this would be an issue with the stereo itself (or whatever the PCI Interface box that they shoved into the box with it ?).
If that is what it sounds like, then I can return this one, and try to buy the proper setup with the TYTO-01 (instead).

Unless if it could be that while experimenting with the 16-pin cable in the car, I busted something really wrong and now the whole wiring inside the car needs to be replaced.



Tagging @soundman98 (since you helped me decipher this stuff before...)

 

i'm not understanding what was re-wired.

in the diagram you posted, you should be working on the "r12" harness. you should only need #1 for battery power, #11 for acc signal, and #20 for ground.

though i have had a few vehicles in the past with a published ground connection that didn't exist-- you might need to connect the radio's ground wire to a metal bracket in the dash.

minimally, you should only need #1 for battery and acc(connect both to simulate the car telling the radio to turn on), and #20 for ground.

also be sure to check fuses! and also try different button sequences. some radio's won't turn on initially until specific buttons are pressed to tell it to start up.

 

So, I found a different set of BAT and GND (one of the places where there was a USB outlet) and I just tap wired into those two for the cable that connects to the radio (#1 and #20), essentially R12 in the diagram.
So, BAT (#1) to GND (#20) circuit voltage stands at 13.5 V.
Should I also do the same with ACC (#11) ?

I had no idea about fuses, maybe I need to figure those out as well. Is there some information on knowing where the specific cable fuses might be ?

 

I just checked the fuses. The two for the radio were blown.
Should've checked for them before I did all that rewiring. Going to have to put it back once I get the fuses replaced!

Hope this works!