how to test kenwood head unit

Hi i wonder if anyone could help please. my son has bought a kenwood kdc-3021 head unit. I would like to test if it works. i thought if i put power to the red and black wires it would light up or something, but nothing happens. the guy in the auto shop said that the conector on it should fit his nova, it did fit but nothing happened. Is it dead or am i doing it wrong. I've checked the fuse thats ok.

Thanks Dave

What you can probably try is connecting the red and yellow wires together and then connecting both of those to the positive side of a car battery and connecting the black wire to the negative side of the battery.  You should then be able to turn it on. 

Duane...

If you think you're confused, imagine how you feel.   

Great that seems to work, the red wire had an extra bit on it the yellow one just pluged into it, i gess thats what its for then.

Thanks for that, Dave

The red wire and yellow wire are not supposed to be connected together except for testing it as described above. The yellow wire is a constant which provides your unit with power. The red wire is a switched 12 volt. It turns the radio on and off with the ignition. If they were always wired together then the radio would always be on and would drain your battery. And the Black is the ground. When wired in the car, they all must be wired to the correct wires in your cars radio harness or it will not turn on and off properly.

OK Thanks, the female plug on the wires fits the male on the car but it did not power up, so if i connect yellow to a perment live then plug in will the rest of the wires be in the correct place, the car is a vauxal nova 1990, i think it was called a opel corsa in other countries. Also there is some other cables that dont go into the plug i am not sure what these are for, 1 says P.CONT 1 says TEL MUTE. If i have to cut this plug off i can work out what are speaker cables there is four pairs of wires, what i don't know is are the plain ones + or the ones with a black stripe on.

Thanks Dave

Hi I have found a manual on line for this, i now know what all the wires are for. Thanks for the help.

It all seems to work but looks like the display has some dead bits.

Dave