Speaker wiring for Pioneer DEH 770 - Pioneer DEH-P770MP CD Player

Depending on the car and your setup sounds like the amplifier is not wired properly or an issue with adjustments on your deck itself. More info on your sound setup would be helpful.

I suggest check this diagram
DEH-3900 Installation Manual -->> DEH_3900MP_CRD4131_installation_manual

1992 Ford Ranger Pickup Truck Car Radio Stereo Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Green/Yellow
Car Radio Accessory Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Chassis
Car Radio Illumination Wire: Blue/Red
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Orange/Green
Left Front Speaker Negative Wire (-): Black/White
Right Front Speaker Positive Wire (+): White/Green
Right Front Speaker Negative Wire (-): Black/White
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Pink/Green
Left Rear Speaker Negative Wire (-): Pink/Blue
Right Rear Speaker Positive Wire (+): Pink/Blue
Right Rear Speaker Negative Wire (-): Green/Orange

Hope helps.

left front +white,-white/black
right front +grey,-grey/black
left rear +green,-green/black
right rear +purple,-purple/black

Orange - 12V constant
Red - 12V switched (acc)
Black - Ground
Green - Left Front +
Green/Black - Left Front -
Grey - Right Front +
Grey/Black - Right Front -
Green/red - Left Rear +
Black Green - Left Rear -
Grey/Red - Right Rear +
Black/Grey - Right Rear -

Pioneer follows the universal after-market color code, so if your CD player was made in the last ten years or so, the wires should go like this:

Yellow: Constant +12VDC (memory)
Red: key-switched +12VDC (accessory)
Black: Ground
Blue/white: amp remote or power antenna output

Speaker wires: The solid-color wire of each pair is positive; the black-striped wire is negative.

Left front: white
Right front: gray
Left rear: green
Right rear: violet

Hope this helps!

Black, red, gray and white (for the front speakers only).
Black: Ground
Red: VCC
Gray: Speaker
White: Speaker.
Remember to isolate any unused cable like the blue (remote), green and purple (rear speaker).

Yellow - +12V Constant Power Red - +12V Switched (accessory) Power Blue - Power Antenna Blue/White - Amp Turn-on White - Left Front Positive Speaker Wire (LF+) White/Black - (LF-) Gray - Right Front Positive Speaker Wire (RF+) Gray/Black - (RF-) Green - Right Rear Positive Speaker Wire (RR+) Green/Black - (RR-) Purple - Left Rear Positive Speaker Wire (LR+) Purple/Black - (LR-)

Yellow: battery power Red: switched power Black: ground White: left front speaker Gray: right front speaker Green: left rear speaker Violet: right rear speaker Wires with stripes are the negative speaker leads.

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