9. O2 Sensor Signal Circuit
With the ignition on.
With the DRB III(R), monitor the O2 Sensor voltage.
Is the voltage below 0.45 volts?
- Yes >> Go To 10
- No >> Check the O2 Signal circuit for a short to ground, open, or short to voltage. Inspect the O2 Sensor connector and the PCM harness connector. If OK, replace and program the Powertrain Control Module. See ELECTRONIC CONTROL MODULES .