9. O2 Sensor Signal Circuit

With the ignition on.

With the DRB III(R), monitor the O2 Sensor voltage.

Fig 1: Monitoring O2 Sensor Voltage

Courtesy of DAIMLERCHRYSLER CORP.

Is the voltage below 0.45 volts? 

1. Yes  >> Go To 10
2. No  >> Check the O2 Sensor Signal circuit for a short to ground, open, or short to voltage. Inspect the O2 Sensor harness connector and the PCM harness connector. If OK, replace and program the Powertrain Control Module. See ELECTRONIC CONTROL MODULES article.

   See POWERTRAIN VERIFICATION TEST - VER 2  .