Diagnostic Procedure

WARNING: This page is about a different car, the 2003 GMC Savana and 2003 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: DTC P1133: HO2S Circuit - Insufficient Switching - Bank 1, Sensor 1 & DTC P1153: HO2S Circuit - Insufficient Switching - Bank 2, Sensor 1 (Steps 1-8)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC P1133: HO2S Circuit - Insufficient Switching - Bank 1, Sensor 1 & DTC P1153: HO2S Circuit - Insufficient Switching - Bank 2, Sensor 1 (Steps 9-13)

Courtesy of GENERAL MOTORS CORP.