Ford Taurus with JBL audio

I was trying to help a friend hook up a different head unit in his car, we bought the correct DIN connector, and connected all the speaker wires to the harness from the HU.  The HU turns on, the cd player works, but no music comes through any of the speakers.  Why is this?  I've tested everything and read all the directions that came with the connector. 

I think with that car there is an amp in the trunk, located on the driver side trunk wall behind the carpeting.  That amp has to by bypassed.  If the amp is there, there should be 2 harneses on the amp.  One is input to the amp, the other is output to the speakers.  There is a special jumper harness you can buy to bypass that amp, or you can figure out all the wiring and hard wire it, but there isn't much room to work under there, so I'd reccommend the jumper harness. 

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well, the amplifier shouldn't be the problem because with the DIN harness for that car with the JBL audio it said that with this the amplifier bypass isn't necessary.  the way the connector works it should be just like any car, except I don't see any speakers wires and i know the flat 8 pin plug is the power/signal/other sh*t wires, and the other square plug with 8 pins is the speaker wires.  There is no way that the plugs can be wrong, i just don't get it.  he doesn't really want to bypass the factory amp because its already there and he wants to use it. 

by not bypassing the factory amplifier you are running the risk of shorting out either the factory amp or the head-unit.  You are doubling up on the power to the speaker and this can cause the speakers to blow.  I'd bypass that amp if i were you.  I have seen too many return (ticked off) customers because an installer did not bypass that amp and it blew his/her speakers.

what year taurus? by the way anyone know a cheap install kit for 2000 on up taurus?

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wait , you hear something sparking?

On that taurus, did you connect the blue white wire on the harness? If not do that, also try powering up the blue wire. Sometimes that factory amp has to be triggered.

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double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer