DTC P0140: O2 Sensor 1/2 Stays At Center: Description
WARNING: This page is about a different car, the 2000 Plymouth Breeze, 2000 Dodge Stratus, and 2000 Chrysler Cirrus. However, it is still accessible from the selected car via links, so may be relevant.
Circuit is monitored with engine running for more than 2 minutes and coolant temperature more than 170°F (77°C) in closed loop. DTC is set when upstream O2 sensor 1/2 signal voltage is between .29-.72 volts for 30 seconds. Possible causes for DTC to set are: intermittent wiring harness failure, O2 sensor 1/2 signal circuit open, O2 sensor 1/2 ground circuit open, defective O2 sensor 1/2 or defective Powertrain Control Module (PCM).