DTC DETECTION LOGIC

The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst 1 causes the longer switching time. To judge the malfunctions of heated oxygen sensor 2, ECM monitors whether the switching response of the sensor's voltage is faster than specified during various driving conditions such as fuelcut.

SEF302U.JPG


DTC No.
Trouble diagnosis name
DTC detecting condition
Possible cause
P0139
Heated oxygen sensor 2 (bank 1) circuit slow response
It takes more time for the sensor to respond between rich and lean than the specified time.
  • Harness or connectors
    (The sensor circuit is open or shorted)
  • Heated oxygen sensor 2
  • Fuel pressure
  • Fuel injector
  • Intake air leaks
P0159
Heated oxygen sensor 2 (bank 2) circuit slow response

 
 DTC CONFIRMATION PROCEDURE

 
 1.INSPECTION START
 
 2.PRECONDITIONING
 
 3.PERFORM DTC CONFIRMATION PROCEDURE
 
 4.PERFORM DTC CONFIRMATION PROCEDURE AGAIN
 
 5.PERFORM COMPONENT FUNCTION CHECK