How to Add AUX to an Old Car Stereo for $2

Here's how to install a direct line-in auxiliary input to a Lexus or Toyota car stereo.

Adding an auxiliary input to your car's outdated stereo is a cost-effective and easy way to modernize your sound system, without upgrading to a cheesy aftermarket looking head unit. This mod will cost $1 for an AUX cable and $1 for a legacy cassette.

A direct line-in aux input will give you clearer sound than a cassette adapter, which is often prone to static and hiss and won't give good bass and treble responses.

This video demonstrates the procedure for radio removal and disassembly on a Lexus GS300. For this project a microphone extension cable was used from the dollar store. It was directly soldered to the "L" and "R" ports coming out of the cassette head before it goes into the equalizer chip.

A blank cassette hacked to infinity loop was used to trick the player into thinking there is a cassette in the deck and to read audio from it.

Furthermore, this video shows you how to replace the burnt out LCD backlighting on the radio. The two incandescent bulbs were replaced with #74 LED's (which are essentially a 5050 SMD LED with a resister soldered to the positive lead).

Using this aux input with a Bluetooth adapter and a ground loop isolator will give you Bluetooth connectivity to the car.