Test Description

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 Pontiac Grand Prix, 2003 Pontiac Bonneville, 2003 Chevrolet Monte Carlo, 2003 Chevrolet Impala, and 2003 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers in the diagnostic procedures.

2

A normally functioning HO2S 1 voltage signal will fluctuate above and below the bias voltage amount.

4

A voltage reading must change from the bias amount to below the specified amount when the signal circuits are jumped to a good ground. This step checks the continuity of the signal circuits.

6

This step verifies that there are functional HO2S 1 heater power and ground circuits.

8

The conditions listed in the table may contribute to the failure of the HO2S. The conditions listed apply only to this type of failure.