DTC P0137, P0157 HO2S2
EC-267
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EC
2006 Pathfinder
DTC P0137, P0157 HO2S2
PFP:226A0
Component Description
UBS00KCY
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air-fuel ratio is controlled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
CONSULT-II Reference Value in Data Monitor Mode
UBS00KCZ
Specification data are reference values.
On Board Diagnosis Logic
UBS00KD0
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 oxy-
gen storage capacity of the three way catalyst (manifold) causes the
longer switching time. To judge the malfunctions of heated oxygen
sensor 2, ECM monitors whether the maximum voltage of the sensor
is sufficiently high during the various driving condition such as fuel-
cut.
SEF327R
MONITOR ITEM
CONDITION
SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)
●
Revving engine from idle to 3,000 rpm quickly after the following condi-
tions are met
–
Engine: After warming up
–
Keeping engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load.
0 - 0.3V
←→
Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)
LEAN
←→
RICH
SEF259VA
DTC No.
Trouble diagnosis name
DTC detecting condition
Possible cause
P0137
0137
(Bank 1)
Heated oxygen sensor
2 circuit low voltage
The maximum voltage from the sensor is not
reached to the specified voltage.
●
Harness or connectors
(The sensor circuit is open or shorted)
●
Heated oxygen sensor 2
●
Fuel pressure
●
Fuel injector
●
Intake air leaks
P0157
0157
(Bank 2)