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LT7804 output Error

1,Pilot 126 pieces, ,it was found that the 4 pieces  ltc7804 chips output abnormal, which should have output 24V, but the output was about 12V. Through the analysis of the bad board, it was found that the output of intvcc was abnormal, which should have output 5V, but only output 0.9V. It was suspected that the chip was damaged, the failure LTC7804  Change to another board, the board dose not work. .

2, The RUN pin passes through the  wire and is manually grounded, r repeated reset of the ltc7804 chip(switch on/off). sometimes, the chip that only outputs 12V can restore the output of 24V. INTVCC output 5V

2. The run pin is tied to 12V through the 100k resistance. use CPU switch it ON and OFF ,  cannot output 24V .