The cooling fans are not engaging. I have went into menu. And tried forcing them on still will not turn on. Voltage at fan shows 11.29 volts far below the required 36. I had this issue with another lift switched out CPU it corrected issue, with CPU from this lift. Which So I sent out cpu to have it rebuilt. I installed it which happens to be the one I had taken CPU from to put in to other truck with inoperative fans which began to work. I know that this truck fans did work before.