Car Radio Help Center

Dedicated to providing technical support and solutions for car radio systems

Carplay undiscoverable

boecky

It is the factory sub that came with the Sony radio.

Leo

Hi boecky,

Thanks for the update!

I just wanted to confirm — have all the wires been properly connected according to the marked points in the diagram I provided earlier?
This area is responsible for the factory subwoofer output, especially for vehicles equipped with the Sony audio system.

If the connections there aren’t correct, the subwoofer might not receive power or audio signal.

Let me know what you find, and I’ll be happy to assist further!

Best regards,
Leo

boecky

Yes, I remember seeing the connection and plugged it in.

Leo

boecky
Hi boecky,

Thank you for confirming the connection. To better assist you with the rear speaker issue, could you please provide the following details:

Speaker Issue Clarification:
- Are both rear speakers not working, or just one side (left/right)?
RCA Connection Check:
- Verify if the red and white RCA plugs from the CANBUS box are connected to the “AUDIO OUT” group in Zone A (not “AUX-IN”).
- Incorrect connection to “AUX-IN” may cause audio malfunction.
Wiring Diagram Request:
- If possible, please share a photo or diagram of your current wiring setup. This will help us diagnose the issue more accurately.

Let us know your findings, and we’ll guide you further!

boecky

One other thing I was going to ask. Why does the system disable bluetooth when using Carplay? It is not an issue, just trying to understand the reasoning.

Leo

boecky
Hi boecky,

Just to add a quick note — in the case of Wireless CarPlay, Bluetooth is still involved but only temporarily. The process works like this:

Bluetooth handshake – your iPhone uses Bluetooth to establish the initial connection with the car.
Switch to Wi-Fi – after pairing, it seamlessly switches to a high-speed Wi-Fi direct link (2.4GHz or 5GHz), which handles all audio/video/Siri/touch data.

So Bluetooth isn’t used during the actual CarPlay session itself — that’s why you might see it disabled or inactive once the system hands over to Wi-Fi.

Hope that helps clarify things!

Best,
Leo

boecky

Leo,

I do know the RCA connections are not plugged in. The harness is laying on my workbench. I will start with that connection and see what happens.

Thanks

boecky

Everything is working to my liking. But, it says I have a Volkswagen Focus. The bottom of the screen is only the volume. See photo

When it is set to Ford Focus, SWC works but skips volume levels and the HVAC buttons do nothing. Even the temp doesn’t match the factory controls, it is Fahrenheit like I wanted. See photo

boecky

Also, the subwoofer is working

Leo

I’d like to know, when operating the physical buttons, does an air conditioning information popup appear on the screen?

boecky

Leo,

Yes, it does. If I would adjust the temp it pops up over what is playing on the screen. There is a double arrow you can push to bring it up manually.

Is this only informational? Can it be turned off?

Leo

boecky
Hi,

Generally speaking, if your original factory screen could not control the A/C, the aftermarket head unit won’t be able to either.

In your specific vehicle, the original A/C control panel is retained—we did not replace it or use any decoder to take over climate control functions. So, any A/C info shown on the screen is for display only, and doesn’t control anything.

If you want to remove or disable the A/C information pop-up, here are two options:

Remove the bottom A/C display bar:
Go to Settings → Car Model → Select RZC → Ford → Focus → Keep. This will hide the lower A/C UI.
Turn off the A/C info pop-up window:
Go to Settings → Factory (password: 3368) → Original Car Agreement → A/C Information ON/OFF, and switch it off.

boecky

Leo,

When I get time, I will set the Car Model to Ford Focus and go through the relearn of the SWC. The factory Sony did have functional controls on the touch screen for the HVAC (see photo). I think this is redundant when you have control right in front of you. The plan is to just turn it off if it is not functional.

I said the rear speaker were functional with the RCA being connect, but know I am not positive on my drive to work today. I need to did deeper into it at a later date.

Thanks

Leo

Thank you for the update. That sounds like a good plan regarding the SWC and HVAC control—it’s always best to keep things as streamlined as possible if physical controls are already easily accessible.

As for the rear speakers via RCA, it’s completely understandable that it might take some time to fully confirm. Whenever you’re able to test it further, feel free to let us know what you find—we’ll be here to assist if anything comes up.

Leo’s AI Assistant