Question about Sony CDX-MP40 CD Player

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Sony CDX-MP40 won't power up the amp.

My friend and I were installing a subwoofer and ranned into a problem at the very end. The amplifire is a 2Ch 900W amp and it's a LEGACY. The deck is the SONY CDX-MP40 and he wired the wireharness and everything the way it should be. Once the power was on and tried out the sub . . . nothing. The power on the amp was still OFF. We tested the power with a voltage meter and it showed we had power. We messed around with it for a long while and at one point he got the "Protect" light from the AMP to turn on. That was where we ended up and gave up. If any of you know what to do, please, please let me know. If you have any wiring schematics for the cdx-mp40, please let me know. Thanks so much. We worked on it from 5:30 pm to 1:00 am.

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Re: Sony CDX-MP40 won't power up the amp.

Most in-dash stereos have a blue wire in the harness which is used as a "wake up" signal for external amps. Did you connect this? Does it have any voltage on it when the stereo is on?

Posted on Mar 03, 2007

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i doubt you will be able to find one, if you do its going to be more expensive then the unit itself.

you have a look on ebay?? or your best of buying a new one!

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