When hooking up a CD player which color goes wit the ground wire?

generally speaking the ground wire is always black and might just be a little thicker

most CD players fitted in to cars come with a wiring diagram on the case of the player

the most common wires are

BLACK (GND) B-

RED (POSITIVE) B+

PINK (MEMORY) B+

YELLOW (AUTO ANTENNIA)

GRAY-TO-GRAY/WHITE (FRONT RIGHT SPEAKER)

BROWN-TO-BROWN/WHITE (FRONT LEFT SPEAKER)

GREEN-TO-GREEN/WHITE (REAR RIGHT SPEAKER)

BLUE-TO-BLUE/WHITE (REAR LEFT SPEAKER)

YOU MAY FIND THAT YOU ALSO HAVE EXTRA SPEAKER WIRES

TO THE DOORS THESE MAY BE PURPLE-TO-PURPLE/WHITE

OR SOME OTHER COLOUR THIS IS DEPENDANT ON THE MAKER OF THE CD

YOUR BEST BET IS TO LOOK ON THE CHASSIE OF THE CD PLAYER AND FOLLOW THE

DIAGRAM ON THERE

AS LONG AS YOU DON'T CONNECT THE BLACK TO THE POSITVE AND THE RED TO THE NEGITVE YOUR OK!