Does anyone know if the audio controls on the steering wheel will still work if the factory head unit is upgraded with an aftermarket one?

 

As long as the aftermarket radio can support the wheel controls I don't see why they wouldn't. Should be simply a matter of connecting the right wire to the right hole.

 

yes, there is an adapter by PAC for all major headunits and brands, its like $50 and allows you to use the controls.

 

correct. Buy the PAC unit if you want the features...do not buy it if you dont

 

I didn't have such great results with the PAC unit (I think it was the SWI-10 or something like that) in my last vehicle. The volume controls worked fine, but could never get it to change channels/songs properly. I called their tech support and they wanted to attribute it to a voltage issue, even though my voltages at the wires they indicated were fine. YMMV...