Blower Fan check start

Check to make sure the fan is to start, press the start button, "Blower Fan" into the start procedure: ① auxiliary pump pre-lubricated one minute (auxiliary pump operation the green light). ② "Blower Fan" to start the operation (blower running green light). ③ relief valve was slowly closed (pressure relief valve green light is off, two minutes after the pressure relief valve is closed green light). ④ auxiliary pump is stopped (auxiliary pump operation indicator is off, stop the red light). So far, the blower starts successfully, it can be put into formal operation. ⑤ After such press the start button, "Blower Fan" failed to start as scheduled, the low oil pressure alarm one minute after the red light, the entire start-up process is stopped. Determine the cause is resolved, restart eliminate the alarm.