If you are installing an aftermarket radio in your 2004 2005 or 2006 Acura TL this combination of harnesses are all you will need. Your radio will need to have 5/6 RCA ports on the back label FL, FR, RR, RL,SUB if your radio does not have these outputs you will need a line out converter found here.
The 20 Pin Blue connector in this combo is used to provide:
– Steering Wheel Control + Lead
– Primary Speakers (FL, FR, RR, RL)
The 26 Pin Grey connector in this combo is used to:
– Amp Turn On for Factory AMP
– Retain Factory Subwoofer
– Retain Factory Navigation touch functions including buttons