Circuit Description

WARNING: This page is about a different car, the 2003 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.

The DTC P0130 Heated Oxygen Sensor (HO2S) Circuit Sensor 1 diagnostic detects an out of range or a fixed HO2S signal. Heated Oxygen Sensor (HO2S) produces a voltage that varies between 100-900 mV. Powertrain Control Module (PCM) monitors this voltage and determines by exhaust gas oxygen content whether air/fuel mixture is rich or lean. When voltage input at PCM is about 100 mV, HO2S is indicating a lean air/fuel mixture. When voltage input is about 900 mV, HO2S is indicating rich air/fuel mixture. PCM constantly monitors HO2S signal during closed loop operation and compensates for rich or lean condition by decreasing or increasing fuel injector pulse width. A DTC P0130 may set if HO2S 1 voltage remains excessively high or low for an extended period of time. See HO2S OPERATION table.

HO2S OPERATION

Air Fuel Mixture	Exhaust O2 Content	HO2S 1 Output	Fuel System Response
Lean Mixture	High Oxygen	Low Voltage	Rich Command
Rich Mixture	Low Oxygen	High Voltage	Lean Command