Possible reasons: enter a signal is abnormal;
Methods: to test whether RuHuXian plenty of video signal input, check whether the power supply line, of the visual extension with normal enough input current and voltage (color extension for 18 v to 24 v, general overpressure will burn product, low pressure will lead to insufficient power supply, and is likely to lead to can't bright screen),
Possible reasons: the line is wrong;
Processing method: please enter a line is normal, whether there is a fault, short circuit, such as joint loose line fault. Note: please use the appropriate line diameter wire. Possible reasons: extension.
Methods: please use the same model, function extension test, pay attention to the extension coding to correct.