Why won't my Si114x or Si1132 device respond to Commands?
The Si1141, Si1142, Si1143, Si1145, Si1146, Si1147, and Si1132 devices have a minimum i2c speed requirement of 90 khz. Writes to the Command register at speeds below this mimimum speed will have unpredictable behavior.
Knowledge Base Articles
It should be mentioned in bold letters in the datasheets thatthese devices do not adhere to the I²C specification where minimum speed is ~zero