Circuit Description

WARNING: This page is about a different car, the 2003 Toyota Camry. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

DTC P0142 indicates deterioration of the heated oxygen sensor No. 3 by the engine control module (ECM) calculating the impedance of the sensor No. 3 after the typical enabling conditions are satisfied (detected after 2 driving-cycles).
DTC P0143 indicates an open or short circuit in the heated oxygen sensor No. 3 system (1 driving-cycle). The ECM determines this by sensing that the impedance of the sensor exceeds the threshold, i.e. less than 5 ohms or more than 5000 ohms. See DTC P0143: OXYGEN SENSOR CIRCUIT LOW VOLTAGE (BANK NO. 1 SENSOR NO. 3) & DTC P0144: OXYGEN SENSOR CIRCUIT HIGH VOLTAGE (BANK NO. 1 SENSOR NO. 3) .

For circuit description, see Fig 1.

Fig 1: DTC P0142 Circuit Description