Conditions for Setting the DTC: P0135

WARNING: This page is about a different car, the 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.

The ECM detects that the sensor temperature remains below a threshold after a specified time after engine start.
The condition exists for more than 100 seconds.
OR
The ECM detects that the calculated HO2S temperature is less than a predetermined threshold with 100 percent heater duty cycle.
The condition exists for more than 100 seconds.