i just bought this new JVC head unit for my 1984 ford f150 and i couldn't find an after market wiring harness so i decided to hardwire it. But when i go to turn it on, it just lights up for a second saying 1:00 as the time and tries to take in a CD. then it shuts off two seconds later and won't turn on again without taking out the key and waiting 10 seconds and trying again. What the hell am i doing wrong? good ground and good hot wire. the accessory is attached too. same with the antenna. i took it back and got a new unit but the same model and it does the same thing?