The new headunit has 4 RCA preouts (front and back, left and right. However, it sounds like there is a data signal that the factory head unit sends to the factory amp to turn it on. Connecting the blue wire doesn't work, needs some computerized signal on two wires labeled (data line).
So I...
I am trying to replace my factory JBL headunit on my 2004 4runner with a Pioneer FHX-720BT . Got it wired in with this JBL amp integration harness . Everything looks right (power, dimmer, etc) by there is no audio from the RCA's of the new headunit to the factory amp in the back cargo by the...
