P0142

DTC P0142 OXYGEN SENSOR CIRCUIT MALFUNCTION (BANK 1 SENSOR 3)

HINT: This DTC has been added to meet the requirement for Partial Zero Emission Vehicle (PZEV).

CIRCUIT DESCRIPTION

DTC Detection Condition:

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

Component Operating Range:

O2S Test Result:

This sensor (heated oxygen sensor 3) is similar to the heated oxygen sensor 2, only difference between the two sensors is that this is not used to regulate the air-fuel ratio. The sensor is located after the rear catalyst (hydrocarbon (HC) absorptive catalyst) only to detect the deterioration in the catalyst.

In a circuit inside the ECM, impedance* of the heated oxygen sensor 3 is measured by the ECM. The ECM determines that there is a malfunction in the sensor when the measured impedance deviates from the standard range.

*: The effective resistance in an alternating current electrical circuit.

HINT: The impedance can not be measured with an ohm meter.

HINT: "P0142 and P0143"
- P0142 indicates deterioration of the heated oxygen sensor 3 by the ECM calculating the impedance of the sensor 3 after the typical enabling conditions are satisfied (detected after 2 driving-cycles).
- P0143 indicates an open or short circuit in the heated oxygen sensor 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 5,000 Ohms.

Wiring Diagram:

CONFIRMATION ENGINE RACING PATTERN FOR READINESS MONITOR

PURPOSE






HINT: Performing this confirmation pattern will activate the heated oxygen sensor 3 monitoring by the ECM. This is very useful for verifying the completion of a repair.

a. Clear the DTCs.
1. Disconnect the battery cable or remove the EFI and ETCS fuses for 60 seconds or more.

b. Connect the hand-held tester to the DLC3.
c. Start the engine and warm it up with all the accessory switches OFF.
d. Run the engine at 2,000 to 3,000 rpm for about 5 minutes.
e. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC INFO / PENDING CODES.

NOTE: If the conditions in this test are not strictly followed, detection of a malfunction will not occur. If you do not have a hand-held tester, turn the ignition switch OFF after performing steps (c) and (d), then perform step (d) again.

INSPECTION PROCEDURE

HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.

REPLACE HEATED OXYGEN SENSOR