Ground wire we have a pioneer cd player (deh-p3099mp) we are just wanting to know where the ground wire connection is in the back?

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How are you wiring the Pioneer DEH 1400 to the Renault?
The Pioneer uses standard radio wiring, you must not have power and ground connected properly if you have nothing happening.

The chassis of the receiver normally is connected to its ground, it should work, but if want to look for the missing cable please follow the color sequence at the rear connector, the ground wire is the third starting from the yellow cable, the second should be the red one, for more details about your receiver please check the user manual at:
http://a248.e.akamai.net/pix.crutchfield.com/Manuals/130/130DEH1700.PDF

broken wire, or dirty connection....oh check your ground wire for radio...

The yellow wire should be connected to unswitched +12V (always powered on) to keep the memory settings.

Black should be ground, and red should be +12V switched power.

check your connections on the radio. check the ground wire. it is very common that the ground wire is to blame.

unhook black wire from harness and the ground from pioneer unit install the ground wire from pioneer unit to frame of car (you may need extra wire to do this) make sure the black wire from pioneer unit is bolted to frame of car not to the harness black wire........fuses will no longer blow and you will have your lights.
hope this helped

you can download a wire diagram from http://audio.manualsonline.com/manuals/mfg/pioneer/dehp5500mp.html

right rear- purple wires
left front- white wires
right front- gray wires
left rear- green wires
BLACK STRIPE NEGATIVE ON ALL
red- 12volts switche
black- ground
yellow- 12volts constant memory

The installation and owner's manual may be found here:
http://www.pioneerelectronics.com/PUSA/Products/CarAudioVideo/Source/CD-Players/DEH-P350?tab=D