The trigger of the new generation CINRAD/CB weather radar provides discharged signals for the modulator. In case of trigger failure, the transmitter cannot work properly. The reasons for failure and the solution are expatiated, based on the analysis of a radar trigger failure event. The main reason of R33 overheating is that the turn on time of the trigger control panel V1 (IRF450, MOSFET) was too long; meanwhile, the excessive power consumption of R33 led to the overload and burnout of the adjustment amplification tube V4, V5(MJ12005) of the trigger power board. Based on the analysis of signal processing circuit diagram and trigger circuitry, the troubleshooting methods and some suggestions to prevent the faults of the like are given, aiming to help technical support staff understand the test and maintenance methods of the trigger.