Installed a new head unit in my 01 dakota quad cab, but there was a purple wire that was connected to the back of the factory head unit, what is that for? Im lost to what that is

 

the violet wire should be the right front speaker +

 

According to the service manual if it is a purple wire with a yellow stripe it is some kind of interface connection between the OE radio, the diagnostic port for the DRB scanner and the Central Timer Module. With an aftermarket radio there should be no connection for this wire to the new radio.

Jimmy

 

Yeah, on an 01 the bus wires are all purple/yellow. This is the wire that makes the remote radio switches work with the factory unit.