INFINITI QX56 2006 Factory Service Manual

EC-50Revision: November 2009
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2006 QX56
A/F SENSOR1 (B2)P0152 0152—×2 ×EC-232
A/F SENSOR1 (B2) P0153 0153××2×EC-241
HO2S2 (B2) P0157 0157××2×EC-253
HO2S2 (B2) P0158 0158××2×EC-264
HO2S2 (B2) P0159 0159××2×EC-277
FUEL SYS-LEAN-B1 P0171 0171——2×EC-288
FUEL SYS-RICH-B1 P0172 0172——2×EC-299
FUEL SYS-LEAN-B2 P0174 0174——2×EC-288
FUEL SYS-RICH-B2 P0175 0175——2×EC-299
FTT SENSOR P0181 0181——2×EC-309
FTT SEN/CIRCUIT P0182 0182——2×EC-315
FTT SEN/CIRCUIT P0183 0183——2×EC-315
TP SEN 1/CIRC P0222 0222——1×EC-320
TP SEN 1/CIRC P0223 0223——1×EC-320
MULTI CYL MISFIRE P0300 0300——2×EC-327
CYL 1 MISFIRE P0301 0301——2×EC-327
CYL 2 MISFIRE P0302 0302——2×EC-327
CYL 3 MISFIRE P0303 0303——2×EC-327
CYL 4 MISFIRE P0304 0304——2×EC-327
CYL 5 MISFIRE P0305 0305——2×EC-327
CYL 6 MISFIRE P0306 0306——2×EC-327
CYL 7 MISFIRE P0307 0307——2×EC-327
CYL 8 MISFIRE P0308 0308——2×EC-327
KNOCK SEN/CIRC-B1 P0327 0327——2—EC-335
KNOCK SEN/CIRC-B1 P0328 0328——2—EC-335
KNOCK SEN/CIRC-B2 P0332 0332——2—EC-335
KNOCK SEN/CIRC-B2 P0333 0333——2—EC-335
CKP SEN/CIRCUIT P0335 0335——2×EC-340
CMP SEN/CIRC-B1 P0340 0340——2×EC-347
TW CATALYST SYS-B1 P0420 0420××2×EC-354
TW CATALYST SYS-B2 P0430 0430××2×EC-354
EVAP PURG FLOW/MON P0441 0441 ××2×EC-360
EVAP SMALL LEAK P0442 0442××2×EC-365
PURG VOLUME CONT/V P0443 0443 ——2×EC-373
PURG VOLUME CONT/V P0444 0444 ——2×EC-381
PURG VOLUME CONT/V P0445 0445 ——2×EC-381
VENT CONTROL VALVE P0447 0447——2×EC-388
VENT CONTROL VALVE P0448 0448——2×EC-395
EVAP SYS PRES SEN P0451 0451——2×EC-402
EVAP SYS PRES SEN P0452 0452——2×EC-405
EVAP SYS PRES SEN P0453 0453——2×EC-411
EVAP GROSS LEAK P0455 0455——2×EC-419
Items
(CONSULT-II screen terms) DTC*
1
SRT code
Test value/
Te s t l i m i t
(GST only) Trip MIL
Refer-
ence page
CONSULT-II
GST*
2ECM*3

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Revision: November 2009 2006 QX56EVAP VERY SML LEAKP0456 0456
×*4× 2×EC-427
FUEL LEV SEN SLOSH P0460 0460——2×EC-436
FUEL LEVEL SENSOR P0461 0461——2×EC-438
FUEL LEVL SEN/CIRC P0462 0462——2×EC-440
FUEL LEVL SEN/CIRC P0463 0463——2×EC-440
VEH SPEED SEN/CIRC*6P0500 0500 ——2×EC-442
ISC SYSTEM P0506 0506——2×EC-444
ISC SYSTEM P0507 0507——2×EC-446
PW ST P SEN/CIRC P0550 0550——2—EC-448
ECM BACK UP/CIRC P0603 0603——2×EC-453
ECM P0605 0605——1 or 2× or — EC-457
SENSOR POWER/CIRC P0643 0643——1×EC-460
TCM P0700 0700——1×AT- 1 0 4
PNP SW/CIRC P0705 0705——2×AT- 1 0 5
ATF TEMP SEN/CIRC P0710 0710——2×AT- 1 2 7
TURBINE REV S/CIRC P0717 0717——2×AT- 1 0 9
VHCL SPD SEN/CIR AT*6P0720 0720 ——2×AT- 11 8
TCC SOLENOID/CIRC P0740 0740——2×AT- 11 8
A/T TCC S/U FNCTN P0744 0744——2×AT- 1 2 0
L/PRESS SOL/CIRC P0745 0745——2×AT- 1 2 2
P-N POS SW/CIRCUIT P0850 0850——2×EC-465
CLOSED LOOP-B1 P1148 1148——1×EC-470
CLOSED LOOP-B2 P1168 1168——1×EC-470
TCS C/U FUNCTN P1211 1211——2—EC-471
TCS/CIRC P1212 1212——2—EC-472
ENG OVER TEMP P1217 1217——1×EC-473
CTP LEARNING P1225 1225——2—EC-483
CTP LEARNING P1226 1226——2—EC-485
ASCD SW P1564 1564——1—EC-487

(Models
with ICC) EC-494

(Models with
ASCD)
ACC COMMAND VALUE*
9P1568 1568 ——1—EC-501
ASCD BRAKE SW P1572 1572——1—EC-502

(Models
with ICC) EC-511

(Models with
ASCD)
Items
(CONSULT-II screen terms) DTC*
1
SRT code
Test value/
Te s t l i m i t
(GST only) Trip MIL
Refer-
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CONSULT-II
GST*
2ECM*3

EC-52Revision: November 2009
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2006 QX56
*1: 1st trip DTC No. is the same as DTC No.
*2: This number is prescribed by SAE J2012.
*3: In Diagnostic Test Mode II (Self-diagnostic results), this number is controlled by NISSAN.
*4: SRT code will not be set if the self-diagnostic result is NG.
*5: The troubleshooting for this DTC needs CONSULT-II.
*6: When the fail-safe operations for both self-diagnoses occur at the same time, the MIL illuminates.
*7: When the ECM is in the mode of displaying SRT status, MIL may flash. For the details, refer to EC-57, "
How to Display SRT Status" .
*8: 2WD models
*9: Models with ICC
DTC AND 1ST TRIP DTC
The 1st trip DTC (whose number is the same as the DTC number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously, and the 1st trip DTC did not reoccur, the 1st trip
DTC will not be displayed.
ASCD VHL SPD SEN*8P1574 1574 ——1—EC-519

(Models
with ICC)
EC-521

(Models with
ASCD)
NATS MALFUNCTION P1610 -
P1615 1610 - 1615
—— 2—BL-137
A/T INTERLOCK P1730 1730——1×AT-134
I/C SOLENOID/CIRC P1752 1752——1×AT-139
I/C SOLENOID FNCTN P1754 1754——1×AT-141
FR/B SOLENOID/CIRC P1757 1757——1×AT-143
FR/B SOLENOID FNCT P1759 1759——1×AT-145
D/C SOLENOID/CIRC P1762 1762——1×AT-147
D/C SOLENOID FNCTN P1764 1764——1×AT-149
HLR/C SOL/CIRC P1767 1767——1×AT-151
HLR/C SOL FNCTN P1769 1769——1×AT-153
LC/B SOLENOID/CIRC P1772 1772——1×AT-155
LC/B SOLENOID FNCT P1774 1774——1×AT-157
BRAKE SW/CIRCUIT P1805 1805——2—EC-523
ETC MOT PWR P2100 2100——1×EC-528
ETC FUNCTION/CIRC P2101 2101——1×EC-534
ETC MOT PWR P2103 2103——1×EC-528
ETC MOT P2118 2118——1×EC-540
ETC ACTR P2119 2119——1×EC-545
APP SEN 1/CIRC P2122 2122——1×EC-547
APP SEN 1/CIRC P2123 2123——1×EC-547
APP SEN 2/CIRC P2127 2127——1×EC-553
APP SEN 2/CIRC P2128 2128——1×EC-553
TP SENSOR P2135 2135——1×EC-560
APP SENSOR P2138 2138——1×EC-567
A/F SENSOR1 (B1) P2A00 2A00—×2 ×EC-575
A/F SENSOR1 (B2) P2A03 2A03—×2 ×EC-575
Items
(CONSULT-II screen terms) DTC*
1
SRT code
Test value/
Te s t l i m i t
(GST only) Trip MIL
Refer-
ence page
CONSULT-II
GST*
2ECM*3

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Revision: November 2009 2006 QX56
If a malfunction is detected during the 1st trip, the 1st trip DTC is stored in the ECM memory. The MIL will not
light up (two trip detection logic). If the same malfunction is not detected in the 2nd trip (meeting the required
driving pattern), the 1st trip DTC is cleared from the ECM memory. If the same malfunction is detected in the
2nd trip, both the 1st trip DTC and DTC are stored in the ECM memory and the MIL lights up. In other words,
the DTC is stored in the ECM memory and the MIL lights up when the same malfunction occurs in two consec-
utive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the 1st and 2nd
trips, only the 1st trip DTC will continue to be stored. For malfunctions that blink or light up the MIL during the
1st trip, the DTC and 1st trip DTC are stored in the ECM memory.
Procedures for clearing the DTC and the 1st trip DTC from the ECM memory are described in EC-61, "
HOW
TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION" .
For malfunctions in which 1st trip DTCs are displayed, refer to EC-49, "
EMISSION-RELATED DIAGNOSTIC
INFORMATION ITEMS" . These items are required by legal regulations to continuously monitor the system/
component. In addition, the items monitored non-continuously are also displayed on CONSULT-II.
1st trip DTC is specified in Service $07 of SAE J1979. 1st trip DTC detection occurs without lighting up the MIL
and therefore does not warn the driver of a malfunction. However, 1st trip DTC detection will not prevent the
vehicle from being tested, for example during Inspection/Maintenance (I/M) tests.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in Work Flow procedure Step 2, refer to EC-84, "
WORK FLOW" . Then perform DTC Confir-
mation Procedure or Overall Function Check to try to duplicate the malfunction. If the malfunction is dupli-
cated, the item requires repair.
How to Read DTC and 1st Trip DTC
DTC and 1st trip DTC can be read by the following methods.
With CONSULT-II
With GST
CONSULT-II or GST (Generic Scan Tool) Examples: P0340, P0850, P1148, etc.
These DTCs are prescribed by SAE J2012.
(CONSULT-II also displays the malfunctioning component or system.)
No Tools
The number of blinks of the MIL in the Diagnostic Test Mode II (Self-Diagnostic Results) indicates the DTC.
Example: 0340, 0850, 1148, etc.
These DTCs are controlled by NISSAN.

1st trip DTC No. is the same as DTC No.

Output of a DTC indicates a malfunction. However, GST or the Diagnostic Test Mode II do not indi-
cate whether the malfunction is still occurring or has occurred in the past and has returned to nor-
mal. CONSULT-II can identify malfunction status as shown below. Therefore, using CONSULT-II (if
available) is recommended.
A sample of CONSULT-II display for DTC and 1st trip DTC is shown below. DTC or 1st trip DTC of a malfunc-
tion is displayed in SELF-DIAGNOSTIC RESULTS mode of CONSULT-II. Time data indicates how many times
the vehicle was driven after the last detection of a DTC.
If the DTC is being detected currently, the time data will be [0].
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II or
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EC-54Revision: November 2009
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2006 QX56
GST. The 1st trip freeze frame data can only be displayed on the CONSULT-II screen, not on the GST. For
details, see EC-118, "
Freeze Frame Data and 1st Trip Freeze Frame Data" .
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM mem-
ory is erased. Procedures for clearing the ECM memory are described in EC-61, "
HOW TO ERASE EMIS-
SION-RELATED DIAGNOSTIC INFORMATION" .
SYSTEM READINESS TEST (SRT) CODE
System Readiness Test (SRT) code is specified in Service $01 of SAE J1979.
As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains
“CMPLT ” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
If, during the state emissions inspection, the SRT indicates “CMPLT” for all test items, the inspector will con-
tinue with the emissions test. However, if the SRT indicates “INCMP” for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If MIL is ON during the state emissions inspection, the vehicle is also returned to the customer untested even
though the SRT indicates “CMPLT ” for all test items. Therefore, it is important to check SRT ( “CMPLT”) and
DTC (No DTCs) before the inspection.
SRT Item
The table below shows required self-diagnostic items to set the SRT to “CMPLT ”.
PriorityItems
1 Freeze frame data Misfire
— DTC: P0300 - P0308
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data
SRT item
(CONSULT-II indication) Performance
Priority* Required self-diagnostic items to set the SRT to
“CMPLT ” Corresponding
DTC No.
CATALYST 2 Three way catalyst function P0420, P0430
EVAP SYSTEM 2 EVAP control system purge flow monitoring P0441 1 EVAP control system P0442
2 EVAP control system P0456

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*: If completion of several SRTs is required, perform driving patterns (DTC confirmation procedure), one by one based on the pr iority for
models with CONSULT-II.
SRT Set Timing
SRT is set as “CMPLT ” after self-diagnosis has been performed one or more times. Completion of SRT is
done regardless of whether the result is OK or NG. The set timing is different between OK and NG results and
is shown in the table below.
OK: Self-diagnosis is carried out and the result is OK.
NG: Self-diagnosis is carried out and the result is NG.
— : Self-diagnosis is not carried out.
When all SRT related self-diagnoses showed OK results in a single cycle (Ignition OFF-ON-OFF), the SRT will
indicate “CMPLT”. → Case 1 above
When all SRT related self-diagnoses showed OK results through several different cycles, the SRT will indicate
“CMPLT ” at the time the respective self-diagnoses have at least one OK result. → Case 2 above
If one or more SRT related self-diagnoses showed NG results in 2 consecutive cycles, the SRT will also indi-
cate “CMPLT ”. → Case 3 above
The table above shows that the minimum number of cycles for setting SRT as “INCMP” is one (1) for each
self-diagnosis (Case 1 & 2) or two (2) for one of self-diagnoses (Case 3). However, in preparation for the state
emissions inspection, it is unnecessary for each self-diagnosis to be executed twice (Case 3) for the following
reasons:

The SRT will indicate “CMPLT ” at the time the respective self-diagnoses have one (1) OK result.

The emissions inspection requires “CMPLT ” of the SRT only with OK self-diagnosis results.

When, during SRT driving pattern, 1st trip DTC (NG) is detected prior to “CMPLT” of SRT, the self-diagno-
sis memory must be erased from ECM after repair.

If the 1st trip DTC is erased, all the SRT will indicate “INCMP”.
HO2S 2 Air fuel ratio (A/F) sensor 1 P0133, P0153
Heated oxygen sensor 2 P0137, P0157
Heated oxygen sensor 2 P0138, P0158
Heated oxygen sensor 2 P0139, P0159
SRT item
(CONSULT-II indication) Performance
Priority* Required self-diagnostic items to set the SRT to “
CMPLT” Corresponding
DTC No.
Self-diagnosis result Example
Diagnosis Ignition cycle
← ON → OFF ← ON → OFF ← ON → OFF ← ON →
All OK Case 1 P0400 OK (1) — (1)OK (2) — (2)
P0402 OK (1) — (1)— (1) OK (2)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “CMPLT ”“ CMPLT”“ CMPLT”“ CMPLT”
Case 2 P0400OK (1) — (1)— (1) — (1)
P0402 — (0) — (0) OK (1) — (1)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “INCMP ”“ INCMP”“ CMPLT”“ CMPLT”
NG exists Case 3 P0400OKOK ——
P0402 ——— —
P1402 NG—NG NG
(Consecutive
NG)
(1st trip) DTC 1st trip DTC
—1st trip DTC DTC
(= MIL ON)
SRT of EGR “INCMP ”“ INCMP”“ INCMP”“ CMPLT”

EC-56Revision: November 2009
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2006 QX56
NOTE:
SRT can be set as “CMPLT” together with the DTC(s). Therefore, DTC check must always be carried out
prior to the state emission inspection even though the SRT indicates “CMPLT”.
SRT Service Procedure
If a vehicle has failed the state emissions inspection due to one or more SRT items indicating “INCMP”, review
the flowchart diagnostic sequence on the next page.
*1 EC-53, "How to Read DTC and 1st
Trip DTC"
*2 EC-57, "How to Display SRT Status"*3EC-57, "How to Set SRT Code"
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How to Display SRT Status
WITH CONSULT-II
Selecting “SRT STATUS” in “DTC CONFIRMATION ” mode with
CONSULT-II.
For items whose SRT codes are set, a “CMPLT ” is displayed on the
CONSULT-II screen; for items whose SRT codes are not set,
“INCMP ” is displayed.
A sample of CONSULT-II display for SRT code is shown in the fig-
ure.
“INCMP ” means the self-diagnosis is incomplete and SRT is not set.
“CMPLT ” means the self-diagnosis is complete and SRT is set.
NOTE:
Though displayed on the CONSULT-II screen, “HO2S HTR” is not
SRT item.
WITH GST
Selecting Service $01 with GST (Generic Scan Tool)
NO TOOLS
A SRT code itself can not be displayed while only SRT status can be.
1. Turn ignition switch ON and wait 20 seconds.
2. SRT status is indicated as shown below.

When all SRT codes are set, MIL lights up continuously.

When any SRT codes are not set, MIL will flash periodically for 10 seconds.
How to Set SRT Code
To set all SRT codes, self-diagnosis for the items indicated above must be performed one or more times. Each
diagnosis may require a long period of actual driving under various conditions.
WITH CONSULT-II
Perform corresponding DTC Confirmation Procedure one by one based on Performance Priority in the table
on EC-54, "
SRT Item" .
WITHOUT CONSULT-II
The most efficient driving pattern in which SRT codes can be properly set is explained on the next page. The
driving pattern should be performed one or more times to set all SRT codes.
SEF935Z
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EC-58Revision: November 2009
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2006 QX56
Driving Pattern
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The time required for each diagnosis varies with road surface conditions, weather, altitude, individual driv-
ing habits, etc.
Zone A refers to the range where the time, required for the diagnosis under normal conditions*, is the
shortest.
Zone B refers to the range where the diagnosis can still be performed if the diagnosis is not completed
within zone A.
*: Normal conditions refer to the following:

Sea level

Flat road

Ambient air temperature: 20 - 30 °C (68 - 86 °F)

Diagnosis is performed as quickly as possible under normal conditions.
Under different conditions [For example: ambient air temperature other than 20 - 30 °C (68 - 86 °F)], diag-
nosis may also be performed.
Pattern 1:

The engine is started at the engine coolant temperature of −10 to 35 °C (14 to 95 °F)
(where the voltage between the ECM terminal 73 and ground is 3.0 - 4.3V).

The engine must be operated at idle speed until the engine coolant temperature is greater than
70 °C (158 °F) (where the voltage between the ECM terminal 73 and ground is lower than 1.4V).

The engine is started at the fuel tank temperature of warmer than 0 °C (32 °F) (where the voltage
between the ECM terminal 107 and ground is less than 4.1V).
Pattern 2:

When steady-state driving is performed again even after it is interrupted, each diagnosis can be con-
ducted. In this case, the time required for diagnosis may be extended.
Pattern 3:

Operate vehicle following the driving pattern shown in the figure.

Release the accelerator pedal during decelerating vehicle speed
from 90 km/h (56 MPH) to 0 km/h (0 MPH).
Pattern 4:

The accelerator pedal must be held very steady during steady-
state driving.

If the accelerator pedal is moved, the test must be conducted all
over again.
*1: Depress the accelerator pedal until vehicle speed is 90 km/h (56
MPH), then release the accelerator pedal and keep it released for
more than 10 seconds. Depress the accelerator pedal until vehicle
speed is 90 km/h (56 MPH) again.
*2: Checking the vehicle speed with GST is advised.
Suggested Transmission Gear Position
Set the selector lever in the D position with the overdrive switch turned ON.
PBIB2244E