How to test whether the optical fiber splitter is faulty

Trial method of optical fiber splitter test instrument:
First, check whether the indicator light of the fiber optic transceiver or optical module and the indicator light of the bai port of the twisted pair end are on
a. If the FX indicator of the transceiver is off, please make sure whether the optical fiber link is cross-linked. One end of the fiber jumper is connected in parallel; the other end is connected in cross mode.
b. If the optical port (FX) indicator of the A transceiver is on and the optical port (FX) indicator of the B transceiver is off, the fault is at the A transceiver: one possibility is: A transceiver (TX) optical transmission The port is broken, because the optical port (RX) of the B transceiver cannot receive the optical signal; another possibility is: the optical fiber link of the optical transmitting port of the A transceiver (TX) has a problem (optical cable or optical jumper may be broken).