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 2 voltage signal will fluctuate above and below the bias voltage amount. The action in the test step should result in a visible reaction from the HO2S 2 output.

4

A voltage reading other than the specified amount in this step indicates an open circuit condition in one of the signal circuits or the PCM.

5

This step inspects for an open circuit condition in the signal circuits, independent of the PCM.

7

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