Originally Posted by hammertime
Heavy Duty, I have the BTA 8100 with the fast harness. Am I understanding correctly that I am better off connecting to the speaker wires in the harness rather than using the rca's? Also, I have a jensen MSR3007 Head unit in my pontoon. I am trying to wire this correctly. I connected the red wire on the Fast harness to the red wire on my head unit harness, it was called acessory/ignition (+), and the blue wire to the blue wire on my head unit that was called (power antenna). The other non/speaker wire choices for these connections was black/shield: rear line audio negative, red: rear right line level out, white: rear left line level out.
I have no power to my sub the way i have it connected. The red wire that I connected the power to is a bit thicker than the other wires. Where am i going wrong???
Try connecting the red wire of the FAST-9999 to the constant +12v of the headunit and connect the blue/white wire of the 9999 to the switched +12v (accessory/ignition).
The advantage of using High Level Inputs over the Low Level (or RCA's) is that when using High Level Inputs you are connecting to a verified high voltage signal.
Post back with any other questions or troublshooting issues.