Where is the auxiliary input jack Chevy Trailblazer 2003?

The 2003 Chevy Trailblazer doesn't have an auxiliary input jack as standard equipment. The factory audio systems in that model year relied on cassette players or CD players. To play music from an external device like an MP3 player, you would need to either:

* Use a cassette adapter: These adapters have a small jack to plug your MP3 player into and a cassette tape shell. You'd play it like a regular cassette.

* Install an aftermarket head unit: Replacing the factory radio with a new one that *does* have an auxiliary input (or better yet, USB and Bluetooth) is the most common solution.

There's no hidden or easily overlooked jack to find.