Question about Pioneer DEH-P6400 CD Player

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No Power to the unit

Can anyone help. My car stereo has lost its power. There is power to the unit, both on the constant battery and ACC wires and through the in line fuse. The unit just will not light up. Any ideas please?

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Re: No Power to the unit

Wiring harness you hooked it up wrong i cannot stress enough that messing with sterio's by self will mess up factory cars harness take old harness out redo the wires make sure there hooked together right if you have too just take it too any car sterio installers and they will splice the wires together for 5 bucks the right way so all you have to do is plug in and mount back up

Posted on Apr 21, 2008

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Re: No Power to the unit

Hi perkyfridge,

You may have a problem with the faceplate connection not making good contact. Tell me what model Radio you have, that will help in determining what is wrong. Thank you.

Posted on Nov 23, 2007

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Connect black to earth or battery negative.
Connect red to battery positive or the acc lead from your ignition switch. If connected to acc the unit will power down when the vehicle is switched off. If connected to battery positive it will remain on irrespective of ignition switch position.
Connect yellow to battery positive for memory power. The moment this lead loses power all the settings/memory on the unit will be lost.
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Not to question you about the red being constant power but I have a pioneer deh-1600 car stereo and red is hooked to electric terminal controlled by ignition switch (on/off) and if your unit has a yellow wire that goes to constant power. The only problem with hooking up the red wire to constant would be if you happened to accidentally leave your player on it could drain the battery. Hope this helped a little. Good luck.

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You need to rewire the red wire on the radio.

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