P0159

Schematic:

The rear Heated Oxygen Sensors (HO2S) are used to determine the oxygen storage capability of the pup converter. Rear O2 diagnostics will run after the sensor has been active for more than 80 seconds, and the catalyst temperature is greater than 600°C (1112°F). If the ECM does not seethe sensor output switching above or below a threshold for a certain time, the ECM will command rich and lean status to make it switch. If the sensor does not react within 100 seconds, this DTC will set, and the sensor will default to open loop.

DTC PARAMETERS
This DTC will set when:
^ The HO2S heater has been running for more than 3 minutes 20 seconds
^ Rear closed loop is active

DTC P0159 is a (type B) DTC

DIAGNOSTIC AIDS
The most probable cause for DTC P0159 is contamination. Check for obvious contamination (oil, fuel, or engine coolant) by removing sensor. Identify and correct the cause of contamination. Replace HO2S bank 2 sensor 2.

NOTE: An intermittent open in the signal wire or ground wire, as well as an inactive sensor; will not set this DTC.