2005 G6, monsoon factory system

i have a 2005 pontiac G6 with the monsoon factory amp, all the research that i have done (searched the net ALL day with as many different combinations of terms as i can think of) ends with the exact oposite of what is happening with my g6, the only sound i am getting is from the tweeters in the mirror trim, i have 12V to the amp, but no sound. I assumed the tweeters are not ran through the amp, unhooked the amp, now nothing. Does the factory head unit have enough power in the speaker channels to sufficiently push sound through the factory speakers? And if it does, how do i bypass the amp without the bypass harness?