me kenwood kdc 627dvd

hi guys new to the forum, ive come on a recommendation that you are the guys to ask when i need help. this problem is giving me a headache, please help me................. i have purchased a 2nd hand kenwood kdc 627dvd head-unit, with the separate brain unit. i found the installation manual on line, and wired it up in the correct way(i think). the red security light is flashing behind the security panel, so i know the unit has power. However, when i connect the security panel, the red light stops flashing( i can peak behind and see its not flashing)as though its detecting the panel, but the unit will do nothing. it wont power on, light up or anything. i know some head-units eject or try to eject a cd when 1st connected, mine doesn't make a sound. there's just nothing. please help me guys, really want to get this going. cheers

did you check to make sure you have both constant and switched power at the radio?Advanced

I had a radio with a detachable face plate, and the security light only blinked when the face was off the unit. There should be Battery, and Ignition (switched) power source wires from the radio. Red us usually switched, and Orange is battery. That's not gospel, it's what I have been working with. Sorry, I cannot find KDC627DVD information, only KVT627DVD.

The hideaway unit also needs to be powered up, is it? Kenwood uses the following color code: red..accessory, yellow..battery, black..ground. They have for years.