2004 INFINITI QX56 load capacity

EC-186Revision: August 2007
DTC P0138, P0158 HO2S2
2004 QX56
DTC P0138, P0158 HO2S2PFP:226A0
Component DescriptionUBS00H2F
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 ModeUBS00H2G
Specification data are reference values.
On Board Diagnosis LogicUBS00H2H
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 voltage is unusually high during
the various driving condition such as fuel-cut.
SEF 3 27 R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quickly.0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
PBIB1848E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0138
0138
(Bank 1)
Heated oxygen sensor
2 circuit high voltageAn excessively high voltage from the sensor is
sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted)

Heated oxygen sensor 2 P0158
0158
(Bank 2)

EC-196Revision: August 2007
DTC P0139, P0159 HO2S2
2004 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.
SEF 3 27 R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quickly.0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
SEF 3 02 U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0139
0139
(Bank 1)
Heated oxygen sensor
2 circuit slow responseIt 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

Injector

Intake air leaks P0159
0159
(Bank 2)

DTC P0420, P0430 THREE WAY CATALYST FUNCTION
EC-267
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: August 20072004 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)
SEF 1 89 Y

DTC P1146, P1166 HO2S2
EC-383
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: August 20072004 QX56
DTC P1146, P1166 HO2S2PFP:226A0
Component DescriptionUBS00H82
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 ModeUBS00H83
Specification data are reference values.
On Board Diagnosis LogicUBS00H84
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 minimum voltage of sensor is
sufficiently low during the various driving condition such as fuel-cut.
SEF 3 27 R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quickly.0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
SEF 5 58 Z
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1146
11 4 6
(Bank 1)Heated oxygen sensor
2 minimum voltage
monitoringThe minimum 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

Injector P1166
11 6 6
(Bank 2)

DTC P1147, P1167 HO2S2
EC-395
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: August 20072004 QX56
DTC P1147, P1167 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 ModeUBS00H8C
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.
SEF 3 27 R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quickly.0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
SEF 5 59 Z
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1147
11 4 7
(Bank 1)
Heated oxygen sensor
2 maximum voltage
monitoringThe 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

Injector

Intake air leaks P1167
11 6 7
(Bank 2)

EM-74Revision: August 2007
CYLINDER BLOCK
2004 QX56
* Refer to GI-45, "Recommended Chemical Products and Sealants" .
DISASSEMBLY
1. Remove engine assembly. Refer to EM-70, "REMOVAL" .
2. Remove the drive plate.

Hold the crankshaft pulley bolt to lock the crankshaft and remove the drive plate bolts.

Loosen bolts diagonally.
CAUTION:

Be careful not to damage drive plate. Especially avoid
deforming and damaging of signal plate teeth (circum-
ference position).

Place the drive plate with signal plate surface facing
other than downward.

Keep magnetic materials away from signal plate.
3. Lift the engine with hoist to install it onto engine stand. Refer to EM-70, "
REMOVAL" .
CAUTION:

Use an engine stand that has a load capacity [approximately 240kg (529 lb) or more] large
enough for supporting the engine weight.

Before removing the hanging chains, make sure the engine stand is stable and there is no risk
of overturning.

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 fuel tube and fuel injector assembly. Refer to EM-29, "REMOVAL" .
–Remove intake manifold. Refer to EM-15, "REMOVAL" .
–Remove exhaust manifold. Refer to EM-19, "REMOVAL" .
–Remove A/C compressor fitting bolts and brackets. Refer to ATC-166, "REMOVAL" .
–Remove ignition coil. Refer to EM-26, "REMOVAL" .
–Remove rocker cover. Refer to EM-33, "REMOVAL" .
–Other removable brackets.
4. Drain engine oil. Refer to MA-16, "
Changing Engine Oil" .
1. Knock sensor sub-harness 2. Knock sensor 3. Cylinder block
4. Main bearing 5. Top ring 6. Second ring
7. Oil ring 8. Crankshaft key 9. Piston
10. Connecting rod 11. Snap ring 12. Piston pin
13. Connecting rod bearing 14. Connecting rod bearing cap 15. Main bearing cap
16. Thrust bearing 17. Main bearing 18. Crankshaft
19. Pilot converter 20. Thrust bearing 21. Side bolt
22. Drive plate 23. Reinforcement plate 24. Rear oil seal retainer
25. Rear oil seal 26. Transmission 27. O-ring
28. Crankshaft position sensor (POS) 29. Gasket 30. Cylinder block heater
31. Connector cap
KBIA2491E

FFD-32
SERVICE DATA AND SPECIFICATIONS (SDS)
Revision: August 20072004 QX56
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
General SpecificationsEDS0035O
Inspection and AdjustmentEDS0035P
DIFFERENTIAL SIDE GEAR CLEARANCE
PRELOAD TORQUE
BACKLASH
COMPANION FLANGE RUNOUT
SELECTIVE PARTS
Side Gear Thrust Washer
*: Always check with the Parts Department for the latest parts information.EngineVK56E
Vehicle gradeAll
Final drive modelM205
2-pinion
Gear ratio3.357:1
Number of teeth (Drive gear/Drive pinion) 47/14
Oil capacity (Approx.)
1.6 (3 3/8 US pt, 2 7/8 lmp pt)
Item Specification
Side gear backlash
(Clearance between side gear and differential case)0.20 mm (0.0079 in) or less
Item Specification
Pinion bearing 2.3 - 3.4 N·m (24 - 34 kg-cm, 21 - 30 in-lb)
Total preload 2.98 - 4.76 N·m (0.31 - 0.48 kg-m, 27 - 42 in-lb)
Item Specification
Drive gear to drive pinion gear 0.12 - 0.20 mm (0.0050 - 0.0079 in)
Item Runout limit
Companion flange face 0.10 mm (0.0039 in)
Inner side of the companion flange 0.13 mm (0.0051 in)
Available side gear
thrust washersThickness mm (in) Package part number*
0.76 (0.030)
0.79 (0.031)
0.81 (0.032)
0.84 (0.033)
0.87 (0.034)38424 8S111
0.89 (0.035)
0.91 (0.036)
0.94 (0.037)
0.97 (0.038)
0.99 (0.039)38424 8S112

RFD-26
SERVICE DATA AND SPECIFICATIONS (SDS)
Revision: August 20072004 QX56
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
General SpecificationsEDS002JQ
Drive Gear RunoutEDS0 02 JR
Unit: mm (in)
Side Gear Adjustment EDS002JS
Unit: mm (in)
AVAILABLE SIDE GEAR THRUST WASHERS
Unit: mm (in)
Drive Pinion Height AdjustmentEDS002JT
AVAILABLE PINION HEIGHT ADJUSTING WASHERS
Unit: mm (in)
Drive Pinion Preload AdjustmentEDS0 02 JU
Grade2WD 4WD
Final drive modelR230 (2 - pinion)
Gear ratio2.937 : 1 3.357 : 1
Number of teeth (drive gear / drive pinion) 47 / 16 47 / 14
Oil capacity (approx.)
1.75 (3 3/4 US pt, 3 1/8 Imp pt)
Final drive modelR230 (2 - pinion)
Drive gear runout limit 0.05 (0.0020) or less
Final drive modelR230 (2 - pinion)
Clearance limit between side gear and differential case 0.20 (0.0079) or less
Final drive modelR230 (2 - pinion)
Thrust washerThickness Part number
1.75 (0.0688) 38424 7S000
1.80 (0.0708) 38424 7S001
1.85 (0.0728) 38424 7S002
Final drive model R230 (2 - pinion)
Adjusting washerThickness Part number Thickness Part number
2.59 (0.1020) 38154 40P00 2.79 (0.1098) 38154 40P10
2.61 (0.1028) 38154 40P01 2.81 (0.1106) 38154 40P11
2.63 (0.1035) 38154 40P02 2.83 (0.1114) 38154 40P12
2.65 (0.1043) 38154 40P03 2.85 (0.1122) 38154 40P13
2.67 (0.1051) 38154 40P04 2.87 (0.1130) 38154 40P14
2.69 (0.1059) 38154 40P05 2.89 (0.1138) 38154 40P15
2.71 (0.1067) 38154 40P06 2.91 (0.1146) 38154 40P16
2.73 (0.1075) 38154 40P07 2.93 (0.1154) 38154 40P17
2.75 (0.1083) 38154 40P08 2.95 (0.1161) 38154 40P18
2.77 (0.1091) 38154 40P09 2.97 (0.1169) 38154 40P19
Final drive modelR230 (2 - pinion)
Drive pinion preload 1.77 − 2.64 N·m (0.18 − 0.26 kg−m, 16 − 23 in-lb)