Test Description

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

1. 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.
2. 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.
3. 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.