DTC P0137, P0157 HO2S2EC-253
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Revision: November 2009 2006 QX56
DTC P0137, P0157 HO2S2PFP:226A0
Component DescriptionUBS00H8B
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 ModeUBS00ODQ
Specification data are reference values.
On Board Diagnosis LogicUBS00H8D
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 ITEMCONDITION 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 the 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
PBIB1154E
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)
EC-264Revision: November 2009
DTC P0138, P0158 HO2S2
2006 QX56
DTC P0138, P0158 HO2S2PFP:226A0
Component DescriptionUBS00N6Y
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 ModeUBS00N6Z
Specification data are reference values.
On Board Diagnosis LogicUBS00N70
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 (manifold) causes the longer switching
time.
MALFUNCTION A
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the voltage is unusually high during the various driving con-
dition such as fuel-cut.
MALFUNCTION B
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the minimum voltage of sensor is sufficiently low during the
various driving condition such as fuel-cut.
SEF327R
MONITOR ITEMCONDITIONSPECIFICATION
HO2S2 (B1)
HO2S2 (B2)
Revving engine from idle to 3,000 rpm quickly after the following conditions
are met.
–Engine: After warming up
–Keeping the 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
PBIB1848E
PBIB2376E
DTC P0139, P0159 HO2S2EC-277
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Revision: November 2009 2006 QX56
DTC P0139, P0159 HO2S2PFP:226A0
Component DescriptionUBS00H2N
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 ModeUBS00H2O
Specification data are reference values.
On Board Diagnosis LogicUBS00H2P
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 switching response of the sen-
sor's voltage is faster than specified during the various driving condi-
tion such as fuel-cut.
SEF327R
MONITOR ITEMCONDITION 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 the 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
SEF302U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0139
0139
(Bank 1) Heated oxygen sensor
2 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
0159
(Bank 2)
EC-354Revision: November 2009
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
2006 QX56
DTC P0420, P0430 THREE WAY CATALYST FUNCTIONPFP:20905
On Board Diagnosis LogicUBS00H4F
The ECM monitors the switching frequency ratio of air fuel sensor
(A/F) sensor 1 and heated oxygen sensor 2.
A three way catalyst (manifold) with high oxygen storage capacity
will indicate a low switching frequency of heated oxygen sensor 2.
As oxygen storage capacity decreases, the heated oxygen sensor 2
switching frequency will increase.
When the frequency ratio of air fuel ratio (A/F) sensor 1 and heated
oxygen sensor 2 approaches a specified limit value, the three way
catalyst (manifold) malfunction is diagnosed.
DTC Confirmation ProcedureUBS00H4G
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
Do not hold engine speed for more than the specified minutes below.
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera- ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S ” indicates more than 70°C
(158 °F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S ” indication reaches to 70 °C (158 °F).
7. Open engine hood.
PBIB2055E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0420
0420
(Bank 1) Catalyst system effi-
ciency below threshold
Three way catalyst (manifold) does not oper-
ate properly.
Three way catalyst (manifold) does not have
enough oxygen storage capacity.
Three way catalyst (manifold)
Exhaust tube
Intake air leaks
Fuel injector
Fuel injector leaks
Spark plug
Improper ignition timing
P0430
0430
(Bank 2)
SEF189Y
EM-76Revision: November 2009
ENGINE ASSEMBLY
2006 QX56
Loosen the bolts diagonally.
CAUTION:
Be careful not to damage the drive plate. Especially
avoid deforming and damaging of the signal plate teeth
(circumference position).
Place the drive plate with the signal plate surface fac-
ing other than downward.
Keep magnetic materials away from the signal plate.
CAUTION:
Use an engine stand that has a load capacity [approximately 240kg (529 lb) or more] large enough
for supporting the engine weight.
If the load capacity of the stand is not adequate, remove the following parts beforehand to
reduce the potential risk of overturning the stand.
–Remove the fuel tube and fuel injector assembly. Refer to EM-31, "Removal and Installation" .
–Remove the intake manifold. Refer to EM-17, "Removal and Installation" .
–Remove the ignition coil. Refer to EM-28, "Removal and Installation" .
–Remove the rocker cover. Refer to EM-35, "Removal and Installation" .
–Other removable brackets.
CAUTION:
Before removing the hanging chains, make sure the engine stand is stable and there is no risk of
overturning.
31. Remove the alternator. Refer to SC-25, "
REMOVAL" .
32. Remove the engine mounting insulator and bracket using power tool.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
When replacing an engine or transmission you must make sure the dowels are installed correctly
during re-assembly.
Improper alignment caused by missing dowels may cause vibration, oil leaks or breakage of driv-
etrain components.
INSPECTION AFTER INSTALLATION
Before starting the engine, check oil/fluid levels including engine coolant and engine oil. If the levels are
lower than required quantity, fill to the specified level. Refer to MA-11, "
Fluids and Lubricants" .
Use procedure below to check for fuel leakage.
Turn ignition switch ON (with engine stopped). With fuel pressure applied to the fuel piping, check for fuel
leakage at the connection points.
Start engine. With engine speed increased, check again for fuel leakage at connection points.
Run engine to check for unusual noise and vibration.
Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids includ-
ing engine oil and engine coolant.
Bleed air from passages in lines and hoses, such as in cooling system.
After cooling down the engine, again check oil/fluid levels including engine oil and engine coolant. Refill to
specified level if necessary.
Summary of the inspection items:
KBIA2491E
SERVICE DATA AND SPECIFICATIONS (SDS)FFD-31
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FFD
Revision: November 2009 2006 QX56
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
General SpecificationsEDS00458
Inspection and AdjustmentEDS00459
DRIVE GEAR RUNOUT
Unit: mm (in)
SIDE GEAR CLEARANCE
Unit: mm (in)
PRELOAD TORQUE
Unit: N·m (kg-m, in-lb)
BACKLASH
Unit: mm (in)
COMPANION FLANGE RUNOUT
Unit: mm (in)
Applied model
VK56E
Final drive model M205
Gear ratio 3.357
Number of teeth (Drive gear/Drive pinion) 47/14
Differential gear oil capacity (Approx.) 1.6 (3 3/8 US pt, 2 7/8 Imp pt)
Number of pinion gears 2
Drive pinion adjustment spacer type Collapsible
ItemRunout limit
Drive gear back face 0.08 (0.0031) or less
ItemSpecification
Side gear back clearance (Clearance between side gear and dif-
ferential case for adjusting side gear backlash) 0.20 (0.0079) or less
(Each gear should rotate smoothly without excessive resistance during differential motion.)
Item Specification
Drive pinion bearing preload torque 2.3 - 3.4 (0.23 - 0.35, 21 - 31)
Total preload torque
(Total preload torque = drive pinion bearing preload torque + side
bearing preload torque). 2.98 - 4.76 (0.31 - 0.48, 27 - 42)
Item
Specification
Drive gear to drive pinion backlash 0.12 - 0.20 (0.0050 - 0.0079)
ItemRunout limit
Companion flange face 0.10 (0.0039) or less
Companion flange inner side 0.13 (0.0051) or less
RFD-32
SERVICE DATA AND SPECIFICATIONS (SDS)
Revision: November 20092006 QX56
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
General SpecificationsEDS0044V
Inspection and AdjustmentEDS0044W
DRIVE GEAR RUNOUT
Unit: mm (in)
SIDE GEAR CLEARANCE
Unit: mm (in)
PRELOAD TORQUE
Unit: N·m (kg-m, in-lb)
BACKLASH
Unit: mm (in)
COMPANION FLANGE RUNOUT
Unit: mm (in)
SELECTIVE PARTS
Side Gear Thrust Washer
Unit: mm (in)
*: Always check with the Parts Department for the latest parts information. Applied model
VK56DE
2WD 4WD
Final drive model R230
Gear ratio 2.9373.357
Number of teeth (Drive gear/Drive pinion) 47 / 1647 / 14
Oil capacity (Approx.) 1.75 (3 3/4 US pt, 3 1/8 Imp pt)
Number of pinion gears 2
Drive pinion adjustment spacer type Collapsible
ItemRunout limit
Drive gear back face 0.05 (0.0020) or less
ItemSpecification
Side gear back clearance
(Clearance limit between side gear and differential case for adjusting
side gear backlash) 0.20 (0.0079) or less
(Each gear should rotate smoothly without excessive resis- tance during differential motion.)
Item Specification
Drive pinion bearing preload torque 1.77 − 2.64 N·m (0.18 − 0.26 kg−m, 16 − 23 in-lb)
Side bearing preload torque (reference value determined by drive
gear bolt pulling force) 0.20
− 0.52 N·m (0.02 − 0.05 kg −m, 2 − 4 in-lb)
Drive gear bolt pulling force (by spring gauge) 34.2 − 39.2 N (3.5 − 4 kg, 7.7 − 8.8 lb)
Total preload torque
(Total preload torque = drive pinion bearing preload torque + Side
bearing preload torque) 2.05
− 4.11 N·m (0.21 − 0.42 kg −m, 19 − 36 in-lb)
Item Specification
Drive gear to drive pinion gear 0.13 − 0.18 (0.0051 − 0.0070)
Item Runout limit
Outer side of the companion flange 0.08 (0.0031) or less
ThicknessPart number*
1.75 (0.0688)
1.80 (0.0708)
1.85 (0.0728) 38424 7S000
38424 7S001
38424 7S002
SC-26
SERVICE DATA AND SPECIFICATIONS (SDS)
Revision: November 20092006 QX56
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
BatteryEKS00B7M
StarterEKS00B7N
GeneratorEKS00B7O
Ty p eGr. 27
Capacity (20 HR) minimum 12V - 80AH
Cold cranking current A
(For reference value) 710
Application
All models
Manufacturer Mitsubishi
M002T85571ZCKD
Ty p e Reduction gear type
System voltage 12V
No-load Terminal voltage
11V
Current Less than 145A
Revolution More than 3,300 rpm
Minimum diameter of commutator 31.4 mm (1.236 in)
Minimum length of brush 11.0 mm (0.433 in)
Brush spring tension 26.7 - 36.1 N (2.72 - 3.68 kg, 5.93 - 8.02 lb)
Clearance between pinion front edge and
pinion stopper 0.5 - 2.0 mm (0.020 - 0.079 in)
Ty p e LR1130-701
Hitachi
Nominal rating 12V - 130A
Ground polarity Negative
Minimum revolution under no-load (When 13.5 volts is applied) 1,200 rpm
Hot output current (When 13.5 volts is applied) More than 78A/1,800 rpm
More than 108A/2,500 rpm
More than 130A/5,000 rpm
Regulated output voltage 14.1 - 14.7V @ 25°C
Minimum length of brush 6 mm (0.24 in)
Brush spring pressure 1.0 - 3.432 N (0.102 - 0.3501 kg, 0.22 - 0.7715 lbs)
Slip ring minimum outer diameter 26 mm (1.02 in)
Rotor (Field coil) resistance 2.1 ohms