Test Description

WARNING: This page is about a different car, the 2003 Cadillac Seville and 2003 Cadillac DeVille. 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.

3

This step determines if the PCM is supplying voltage from the high side driver through the HO2S bank 1 sensor 1 heater high control circuit.

4

This step determines if ignition 1 voltage is being supplied from the underhood fuse block. The battery voltage in this step indicates a functional low control circuit for both front sensors.

7

The bank 1 sensor 1 and the bank 2 sensor 1 low control circuits are internally connected within the PCM. A short to ground between the HO2S bank 2 sensor 1 low control circuit and the PCM will set this DTC.