DTC P0134: Ho2S Circuit - Insufficient Activity - Sensor 1: Description
WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
The Powertrain Control Module (PCM) supplies a voltage of about 447 mV between the Heated Oxygen Sensor 1 (HO2S 1) high signal and the low signal circuit. The HO2S 1 varies the voltage within a range of about 1000 mV if the exhaust is rich, down through about 100 mV if the exhaust is lean. The sensor is like an open circuit and produces no voltage when below 600°F (315°C). Do not attempt to repair the HO2S. Replace the entire HO2S 1 assembly if the following conditions exist:
- Damaged wiring.
- Damaged electrical connector.
- Damaged terminals.