Upgrading Car Radio

"Spotify take the wheel!" with a custom 3.5mm jack.

My brother and I share our grandmas old car, it’s a beautiful Renault Mégane 2.0 from 1998. However, we wanted to listen to our own music, unfortunately the car only supported radio or cassette. So a new project was conceived.

The radio removed from its enclosure to find the model number.

I removed the car radio from its socket to inspect the model type. A search on Google bought me to the manual, luckily back in the day companies still provide in-depth electronic schematics for their products.

The diagram of the PCB including the cassete amplifier.

Inspecting the schematics allowed be to identify the cassette amplifier.

The red and blue wires are the L and R channel soldered into the cassete amplifier. The black wire is the grounding.
The resulting 3.5mm jack neatly inserted in the corner of the radio front.

So I soldered in an 3.5mm female port parallel to the cassette input. This ensured the 3.5mm output from my phone would be properly amplified before it’s sent to car the speakers.

Update 2021

The custom AUX port is still going strong and has allowed me and my brother to listen to many hours of music and podcasts.

Update 2022

The radio outlived the car :(