单项选择题
A.14.7:1B.14.75:1C.14.2:1D.13.7:1
A.0-5VB.1-2VC.0-12VD.3-5V
A.供电线断路B.供电电压5VC.搭铁线对地0.1ΩD.水温传感器损坏