DSR-250 Blue Screen

Hi, I have a DSR-250 that I just got this week. I have recorded to DVCAM tape (sony) and it played back great. So on to the othere step of testing this out I read about recharging the clock battery. I Did , well 24Hrs later I did another test recording just like 2min long out side in 25F clear weather, and came back in to play the tape back , It did .... went to hook SVIDEO to 37" TV , Pressed play , nothing but blue video out , when back into the test area and hooked back up to BNC , then Svideo , NOTING just Blue on the play back , did recording and play noting at on seems to be on the tape .

Might anyone have info on cleaning the heads and or what might be up ?
Is there a switch or menu setting that is " reset " from the recharging ?

well i opened the cam with the help of another tech and we cleaned the head with 91% Isopropyl alcohol. and now it works.

Are Sony DVCAM and DV tapes Junk?
i have 700+ hrs on this DSR250