Answer: if the im1281b electric energy metering module encounters communication failure, first check whether the communication parameters of the 

module are set correctly (including serial port number, baud rate, check bit, etc.), then check whether the power indicator is on, and check whether there 

is cross wiring between the communication RX and TX. if there is no abnormality as mentioned above, or the communication fails, short circuit the 

resistance according to the following figure and retest (caused by the difference between different USB to TTL matchers). Communication is generally 

successful.