P0161

System Description
The ECM performs ON/OFF control of the heated oxygen sensor 2 heaters (rear) corresponding to the engine speed.

Operation:

Consult-II Reference Value In Data Monitor Mode:

ECM Terminals And Reference Value:

On Board Diagnosis Logic
Malfunction is detected when the current amperage in the heated oxygen sensor 2 heater (rear) circuit is out of the normal range. [An improper voltage drop signal is sent to ECM through the heated oxygen sensor 2 heater (rear).]

POSSIBLE CAUSE
- Harness or connectors
(The heated oxygen sensor 2 heater (rear) circuit is open or shorted.)
- Heated oxygen sensor 2 heater (rear)

DTC Confirmation Procedure

NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch OFF and wait at least 5 seconds before conducting the next test.

TESTING CONDITION: Before performing the following procedure, confirm that battery voltage is between 10.5 V and 16 V at idle.

With CONSULT-II
1. Turn ignition switch ON and select "DATA MONITOR" mode with CONSULT-II.
2. Start engine.
3. Drive vehicle at a speed of more than 70 km/h (43 MPH) for 2 consecutive minutes.




4. Stop vehicle and let engine idle for at least 6 seconds.
5. If 1st trip DTC is detected, go to "Diagnostic Procedure" below.

With GST
Follow the procedure "With CONSULT-II".

Wiring Diagram

EC-O2H2B2-01:

EC-O2H2B2-01 Connector View:

Diagnostic Procedure

Steps 1 - 2:

Steps 3 - 4:

Step 5:

Steps 6 - 7: