I need some help, I want to install a sub and wanted to know if there is a connection on the 2009 stock head unit to connect the sub or if I’d need to tap it, thought I’d ask before I started taking the head unit out 

11 hours ago, Dannyboy16 said:

I need some help, I want to install a sub and wanted to know if there is a connection on the 2009 stock head unit to connect the sub or if I’d need to tap it, thought I’d ask before I started taking the head unit out 

Hi,

No factory headunit had RCA connection in the back,

So before taking out the headunit you need to purchase a 

High to low level RCA adapter 

Then splice it in to your rear speaker output and plug the RCA's from your amplifier into it, dont worry if space is limited at the rear of the factory headunit, you can use some speaker cable to splice in to the speaker outputs then extend the length down to a more suitable location to fit the Hi to Low Level RCA adapter.

Aside from this is your amplifier and sub two separate items or did you purchase an all-in-one unit ? 

If the amp is separate to the sub then it may not be tuned correctly; in which case I recommend using a multimeter and syn wave CD to tune the amplifier sensitivity for optimum output without distortion 

I myself have a full JL Audio aftermarket system with pioneer headunit. 

Needless to say it levitates 🥴