The BQ76922 device implements a comparison check between the two voltage references by measuring the REG18 voltage (which is based on VREF2) using the voltage ADC (which uses VREF1 as its reference). The resulting measurement can be read back in bytes 0–1 of the 0x0075 DASTATUS5() subcommand.

This command should normally report a value of approximately 29137. If it differs significantly from this, it may indicate that one reference has changed in value significantly relative to the other, meaning reported measurements may no longer be accurate. This ratio is monitored periodically and, if the value is below 26223 or above 32051 for four seconds, the device can trigger a Permanent Fail (PF) and disable the battery pack. This PF can be enabled by setting the Settings:Permanent Failure:Enabled PF C[VREF] configuration bit.