The landscape of aftermarket and OEM car stereos is more complicated today.

It’s an umbrella term that includes everything fromGPS navigationtoBluetooth integrationandin-car multimedia.

A growing percentage of new cars sold each year come with these systems instead of basic head units.

Some infotainment systems are difficult to operate without taking your eyes off the road, but they may have useful features you don't want to lose.

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You may want to retain some features of your vehicle’s infotainment system while letting go of others.

It’s important to consider this when looking at upgrade options.

Wiring harnesses are at the root of any head unit upgrade.

There are a few ways they can come into play.

Toretain steering wheel audio control functionality, you need two things: a compatible head unit and an adapter.

The first part is relatively easy due to the prevalence of this feature in cars.

In some cases, you may need to cut and splice some wires to complete the installation.

In other cases, it’s a matter of plugging in the necessary harness adapters.

Still, you will typically end up with a relatively clean-looking installation.