I recently purchased a BL4s package in used but decent condition. I'm pretty excited about the camera but so far have not been able to get it to run. The previous owner stated the camera is running and good to go. The motor turns over but then stops right away. I bought the Arriflex 35 book and have been combing through but it doesn't describe this issue. When I plug the battery in (Bescor 12v 14.4ah) I get a quick beep tone. Then when I flip the cam switch the motor kicks but then stops half a second later. More like a quick jolt. The leds come on and I was able to reset the footage counter. I also checked the fuses and none of them appear to be blown. The camera came with a precision speed controller which I tried as well and that does the same thing. If anyone has any advice that would be great.