Diagnosis Conditions

Fig 1: DTC P0156 Diagnosis Conditions

Courtesy of PORSCHE OF NORTH AMERICA, INC.

The DME control module stores DTC P0156 when the sensor voltage is less than 60 mV for more than 60 seconds during active oxygen sensing after the TWC.

Fig 2: DTC P0156 Fault Conditions

Courtesy of PORSCHE OF NORTH AMERICA, INC.

NOTE: In the event of a fault in the mixture system and uncontrolled fresh air injection (secondary air injection system) or a leaking exhaust system in front of the sensor, the sensor voltage may lie around 0V for a longer period, thereby wrongly indicting a fault.