I know this has been ask before but I have a 2001 ram with infinity speakers. I recently put in a new radio and bought the harnesses to go with it. I plugged it all in and got power but no sound came from the speakers. Speakers are not blown and the stock radio still works when I plug it in but when I use the aftermarket radio I cannot get sound. Are there certain wires that need to be switched or something? Thanks for the help everyone

 

Sounds like it may not be wired right, how did you hook it up?

 

Bypass amps on infinity stock speakers.

Just run new wire, don't try to jump to through all the loops to get them to work

 

I connected the harnesses and wires with their respective recipients on the harness and everything looks to connected correctly.
And is there a way I could still use the factory amp?

 

+1 to Hambone.

The front Infinity speakers have their own amps and aren't powered by the stock headunit. The rear speakers ARE powered by the stock headunit. So you're running the same power through both with your new headunit. (which is fine, that's how most OE systems are anyway)