BQ27531-G1: Over Temperature not working

Part Number:BQ27531-G1

Hi,

We are Temperature testing our system with the BQ27531-G1/BQ24192 ICs. OT is set to 40C while the UT is set to 0C.

For UT testing, charging cuts off when the temp is around 1C, and then charging starts when the temp is ramped up to 2.45C, so this works fine.

For OT testing, the charging didn't cut off at 40C, and still charging at around 47C. We checked the OT register in the BQStudio, and it's configured correctly.

Any ideas why UT protection worked and the OT didn't? 

Thanks