I have a 2004 holden barina an need a radio code?

SOURCE: holden barina 2003

it means its due for service. If u wanna get rid of it without servicing the vehicle then as you start the car simultaneously push the ODOMETER reset button on the dash and it will wipe it. This will however just delay the point your car needs servicing.

SOURCE: Locked stereo in 1995 Holden Barina

I dont know if holden barina uses the same stereo as a US GM vehicle, but if it is a delco stereo (same as US models) then any gm dealer can retrieve the scrambled code and call their automated system to get the unscrambled unlock code. Just make sure if they do this for you to have them disable the theftlock system. With theftlock disabled a dead battery will not cause you any further problem. Hope this helps.

SOURCE: changing a fuel pump on a 1991 holden barina

The Fuel Pump is Inside the Fuel Tank. You will need to Trop the Fuel tank for this. Not an Easy Job by any Means.

SOURCE: wire colour coding for radio Holden Nova LF

Car Radio Constant 12v+ Wire: Blue/Yellow
Car Radio Switched 12v+ Wire: Gray
Car Radio Ground Wire: Brown
Car Radio Illumination Wire: Green
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 (+): Pink
Left Front Speaker Negative Wire (-): Violet
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Blue
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Black
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Red
Right Rear Speaker Negative Wire (-): White

SOURCE: I need a free workshop manual for 1.3l 1991 holden

http://www.teamswift.net/viewtopic.php?t=26290

This might be what you are looking for It is on an MK1 But i think it is the same for a Barina

If not search the site for lots of good info.