WARNING: This page is about a different car, the 2003 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: DTC P1031: HO2S Bank 1 Sensor 1 Heater Current Monitor Control Circuit & P1032: HO2S Bank 2 Sensor 1 Heater Current Monitor Control Circuit (Steps 1-4)
Courtesy of GENERAL MOTORS CORP.
Fig 2: DTC P1031: HO2S Bank 1 Sensor 1 Heater Current Monitor Control Circuit & P1032: HO2S Bank 2 Sensor 1 Heater Current Monitor Control Circuit (Steps 5-15)