check engine light INFINITI QX56 2009 Factory Workshop Manual
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![INFINITI QX56 2009 Factory Workshop Manual
EC-354
< COMPONENT DIAGNOSIS >[VK56DE]
P2101 ELECTRIC THROTTLE CONTROL FUNCTION
P2101 ELECTRIC THROTTL
E CONTROL FUNCTION
DescriptionINFOID:0000000003771665
NOTE:
If DTC P2101 is displayed with DT C INFINITI QX56 2009 Factory Workshop Manual
EC-354
< COMPONENT DIAGNOSIS >[VK56DE]
P2101 ELECTRIC THROTTLE CONTROL FUNCTION
P2101 ELECTRIC THROTTL
E CONTROL FUNCTION
DescriptionINFOID:0000000003771665
NOTE:
If DTC P2101 is displayed with DT C](/img/42/57031/w960_57031-1680.png)
EC-354
< COMPONENT DIAGNOSIS >[VK56DE]
P2101 ELECTRIC THROTTLE CONTROL FUNCTION
P2101 ELECTRIC THROTTL
E CONTROL FUNCTION
DescriptionINFOID:0000000003771665
NOTE:
If DTC P2101 is displayed with DT C P2100 or 2119, first perform the trouble diagnosis for DTC P2100
or P2119. Refer to EC-351
or EC-360 .
Electric throttle control actuator consists of th rottle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control mo tor to make the throttle valve opening angle properly in
response to driving condition.
On Board Diagn osis LogicINFOID:0000000003771666
This self-diagnosis has the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000003771667
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V when engine
is running.
1. Turn ignition switch ON and wait at least 2 seconds.
2. Start engine and let it idle for 5 seconds.
3. Check DTC.
4. If DTC is detected, go to EC-354, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771668
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2101
2101 Electric throttle control
performance Electric throttle control function does not oper-
ate properly. Harness or connectors
(Throttle control motor circuit is open or
shorted)
Electric throttle control actuator
Engine operating condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) b y the return
spring.
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Workshop Manual
EC-358
< COMPONENT DIAGNOSIS >[VK56DE]
P2118 THROTTLE CONTROL MOTOR
P2118 THROTTLE CONTROL MOTOR
Component DescriptionINFOID:0000000003771670
The throttle control motor is operated by the ECM and it INFINITI QX56 2009 Factory Workshop Manual
EC-358
< COMPONENT DIAGNOSIS >[VK56DE]
P2118 THROTTLE CONTROL MOTOR
P2118 THROTTLE CONTROL MOTOR
Component DescriptionINFOID:0000000003771670
The throttle control motor is operated by the ECM and it](/img/42/57031/w960_57031-1684.png)
EC-358
< COMPONENT DIAGNOSIS >[VK56DE]
P2118 THROTTLE CONTROL MOTOR
P2118 THROTTLE CONTROL MOTOR
Component DescriptionINFOID:0000000003771670
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected
by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control mo tor to make the throttle valve opening angle properly in
response to driving condition.
On Board Diagn osis LogicINFOID:0000000003771671
This self-diagnosis has the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000003771672
1. If DTC Confirmation Procedure has been previously conducted, always perform the following before con-
ducting the next step.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Turn ignition switch ON.
c. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Start engine and let it idle for 5 seconds.
4. Check DTC.
5. If DTC is detected, go to EC-358, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771673
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-85, "Ground Inspection"
.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2118
2118 Throttle control motor
circuit short ECM detects short in both circuits between
ECM and throttle control motor. Harness or connectors
(Throttle control motor circuit is shorted.)
Electric throttle control actuator
(Throttle control motor)
Engine operating condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) b y the return
spring.
BBIA0354E
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EC-360
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P2119 ELECTRIC THROTTLE CONTROL ACTUATOR
P2119 ELECTRIC THROTTLE CONTROL ACTUATOR
Component DescriptionINFOID:0000000003771675
Electric throttle control actuato INFINITI QX56 2009 Factory Workshop Manual
EC-360
< COMPONENT DIAGNOSIS >[VK56DE]
P2119 ELECTRIC THROTTLE CONTROL ACTUATOR
P2119 ELECTRIC THROTTLE CONTROL ACTUATOR
Component DescriptionINFOID:0000000003771675
Electric throttle control actuato](/img/42/57031/w960_57031-1686.png)
EC-360
< COMPONENT DIAGNOSIS >[VK56DE]
P2119 ELECTRIC THROTTLE CONTROL ACTUATOR
P2119 ELECTRIC THROTTLE CONTROL ACTUATOR
Component DescriptionINFOID:0000000003771675
Electric throttle control actuator consists of th
rottle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The throttle position sensor detects the throttle va lve position, and the opening and closing speed of the throt-
tle valve and feeds the voltage signals to the ECM. T he ECM judges the current opening angle of the throttle
valve from these signals and the ECM controls the thrott le control motor to make the throttle valve opening
angle properly in response to driving condition.
On Board Diagn osis LogicINFOID:0000000003771676
This self-diagnosis has one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000003771677
NOTE:
Perform PROCEDURE FOR MALFUNCTION A AND B first. If the DTC cannot be confirmed, perform
PROCEDURE FOR MALFUNCTION C.
If DTC Confirmation Procedure has been previously conducted, always perform the following before con-
ducting the next step
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
PROCEDURE FOR MALFUNCTION A AND B
1. Turn ignition switch ON and wait at least 1 second.
2. Shift selector lever to D position and wait at least 3 seconds.
3. Shift selector lever to P or N position.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Turn ignition switch ON and wait at least 1 second.
6. Shift selector lever to D position and wait at least 3 seconds.
7. Shift selector lever to P or N position.
8. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
9. Check DTC.
10. If DTC is detected, go to EC-361, "Diagnosis Procedure"
.
PROCEDURE FOR MALFUNCTION C
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2119
2119 Electric throttle control
actuator A)
Electric throttle control
actuator does not func-
tion properly due to the return spring malfunc-
tion. Electric throttle control actuator
B) Throttle valve opening angle in fail-safe mode is
not in specified range.
C) ECM detect the throttle valve is stuck open.
Detected items Engine operating condition in fail-safe mode
Malfunction A The ECM controls the electric throttle actuator by regulating the throttle opening around the idle position.
The engine speed will not rise more than 2,000 rpm.
Malfunction B ECM controls the electric throttle control actuator by regulating the throttle opening to 20 degrees or less.
Malfunction C While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops, the engine stalls.
The engine can restart in N or P position, and engine speed will not exceed 1,000 rpm or more.
Revision: December 20092009 QX56
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EC-362
< COMPONENT DIAGNOSIS >[VK56DE]
P2122, P2123 APP SENSOR
P2122, P2123 APP SENSOR
Component DescriptionINFOID:0000000003771679
The accelerator pedal position sensor is installed on the upper end INFINITI QX56 2009 Factory Workshop Manual
EC-362
< COMPONENT DIAGNOSIS >[VK56DE]
P2122, P2123 APP SENSOR
P2122, P2123 APP SENSOR
Component DescriptionINFOID:0000000003771679
The accelerator pedal position sensor is installed on the upper end](/img/42/57031/w960_57031-1688.png)
EC-362
< COMPONENT DIAGNOSIS >[VK56DE]
P2122, P2123 APP SENSOR
P2122, P2123 APP SENSOR
Component DescriptionINFOID:0000000003771679
The accelerator pedal position sensor is installed on the upper end
of the accelerator pedal assembly. The sensor detects the accelera-
tor position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerato
r pedal is determined by the ECM
receiving the signal from the accelerator pedal positi on sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
On Board Diagn osis LogicINFOID:0000000003771680
These self-diagnoses have the one trip detection logic.
NOTE:
If DTC P2122 or P2123 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-285
.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000003771681
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-362, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771682
1.CHECK GROUND CONNECTIONS
PBIB1741E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2122
2122 Accelerator pedal position
sensor 1 circuit low input An excessively low vo
ltage from the APP sen-
sor 1 is sent to ECM. Harness or connectors
(The APP sensor 1 circuit is open or
shorted.)
Accelerator pedal position sensor (Accelerator pedal position sensor 1)
P2123
2123
Accelerator pedal position
sensor 1 circuit high input An excessively high vo
ltage from the APP sen-
sor 1 is sent to ECM.
Engine operating condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.
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P2127, P2128 APP SENSOREC-365
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P2127, P2128 APP SENSOR
Component DescriptionINFOID:0000000003771684
The accelerator pedal position sens INFINITI QX56 2009 Factory Workshop Manual
P2127, P2128 APP SENSOREC-365
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P2127, P2128 APP SENSOR
Component DescriptionINFOID:0000000003771684
The accelerator pedal position sens](/img/42/57031/w960_57031-1691.png)
P2127, P2128 APP SENSOREC-365
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P2127, P2128 APP SENSOR
Component DescriptionINFOID:0000000003771684
The accelerator pedal position sensor is installed on the upper end
of the accelerator pedal assembly. The sensor detects the accelera-
tor position and sends a signal to the ECM.
Accelerator pedal position sensor
has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal positi on sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
On Board Diagnosis LogicINFOID:0000000003771685
These self-diagnoses have the on e trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM ent ers fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000003771686
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-365, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771687
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
PBIB1741E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2127
2127 Accelerator pedal position
sensor 2 circuit low input An excessively low voltage from the APP
sensor 2 is sent to ECM. Harness or connectors
(APP sensor 2 circuit is open or shorted.)
(TP sensor circuit is shorted.)
Accelerator pedal position sensor (Accelerator pedal position sensor 2)
Electric throttle control actuator
(TP sensor)
P2128
2128
Accelerator pedal position
sensor 2 circuit high input An excessively high
voltage from the APP
sensor 2 is sent to ECM.
Engine operating condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.
Revision: December 20092009 QX56
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P2135 TP SENSOREC-369
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P2135 TP SENSOR
Component DescriptionINFOID:0000000003771689
Electric throttle control actuator
consists of thr INFINITI QX56 2009 Factory Workshop Manual
P2135 TP SENSOREC-369
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P2135 TP SENSOR
Component DescriptionINFOID:0000000003771689
Electric throttle control actuator
consists of thr](/img/42/57031/w960_57031-1695.png)
P2135 TP SENSOREC-369
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P2135 TP SENSOR
Component DescriptionINFOID:0000000003771689
Electric throttle control actuator
consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has t he two sensors. These sensors are
a kind of potentiometers which transform the throttle valve position
into output voltage, and emit the voltage signal to the ECM. In addi-
tion, these sensors detect t he opening and closing speed of the
throttle valve and feed the voltage signals to the ECM. The ECM
judges the current opening angle of the throttle valve from these sig-
nals and the ECM controls the throttle control motor to make the
throttle valve opening angle properly in response to driving condi-
tion.
On Board Diagnosis LogicINFOID:0000000003771690
This self-diagnosis has the on e trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000003771691
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-369, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771692
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2135
2135 Throttle position sensor
circuit range/performance Rationally incorrect voltage is sent to ECM
compared with the signals from TP sensor 1
and TP sensor 2. Harness or connector
(TP sensor 1 and 2 circuit is open or
shorted.)
(APP sensor 2 circuit is shorted.)
Electric throttle control actuator (TP sensor 1 and 2)
Accelerator pedal position sensor
(APP sensor 2)
Engine operation condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Workshop Manual
P2138 APP SENSOREC-373
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P2138 APP SENSOR
Component DescriptionINFOID:0000000003771694
The accelerator pedal position sensor is installe INFINITI QX56 2009 Factory Workshop Manual
P2138 APP SENSOREC-373
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P2138 APP SENSOR
Component DescriptionINFOID:0000000003771694
The accelerator pedal position sensor is installe](/img/42/57031/w960_57031-1699.png)
P2138 APP SENSOREC-373
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P2138 APP SENSOR
Component DescriptionINFOID:0000000003771694
The accelerator pedal position sensor is installed on the upper end
of the accelerator pedal assembly. The sensor detects the accelera-
tor position and sends a signal to the ECM.
Accelerator pedal position sensor
has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal positi on sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
On Board Diagnosis LogicINFOID:0000000003771695
This self-diagnosis has the on e trip detection logic.
NOTE:
If DTC P2138 is displayed with DTC P0643, first pe rform the trouble diagnosis for DTC P0643. Refer to
EC-285
.
FAIL-SAFE MODE
When the malfunction is detected, ECM ent ers fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000003771696
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-374, "Diagnosis Procedure"
.
PBIB1741E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2138
2138 Accelerator pedal position
sensor circuit range/per-
formance Rationally incorrect voltage is sent to ECM
compared with the signals from APP sensor 1
and APP sensor 2. Harness or connector
(APP sensor 1 and 2 circuit is open or
shorted.)
(TP sensor circuit is shorted.)
Accelerator pedal position sensor 1 and 2
Electric throttle control actuator
(TP sensor)
Engine operating condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.
Revision: December 20092009 QX56
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ECM
EC-461
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Procedures for clearing the DTC and the 1st trip DT
C from the ECM memory are described in "HOW TO
ERASE EMISSION-RELATED DIAGNOS INFINITI QX56 2009 Factory Workshop Manual
ECM
EC-461
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Procedures for clearing the DTC and the 1st trip DT
C from the ECM memory are described in "HOW TO
ERASE EMISSION-RELATED DIAGNOS](/img/42/57031/w960_57031-1787.png)
ECM
EC-461
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Procedures for clearing the DTC and the 1st trip DT
C from the ECM memory are described in "HOW TO
ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION".
For malfunctions in which 1st trip DTCs are displa yed, refer to "EMISSION-RELATED DIAGNOSTIC INFOR-
MATION ITEMS". These items are required by legal r egulations to continuously monitor the system/compo-
nent. In addition, the items monitored non-cont inuously are also displayed on CONSULT-III.
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-8, "Trouble Diagnosis Introduction"
. Then per-
form DTC Confirmation Procedure or Overall Function Che ck to try to duplicate the malfunction. If the mal-
function is duplicated, 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-III
With GST
CONSULT-III or GST (Generic Scan Tool ) Examples: P0340, P0850, P1148, etc.
These DTCs are prescribed by SAE J2012.
(CONSULT-III 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 malfunc tion. However, GST or the Diagnostic Test Mode II do not indi-
cate whether the malfunction is stil l occurring or has occurred in the past and has returned to nor-
mal. CONSULT-III can identify malfunction status as shown below. Therefore, using CONSULT-III (if
available) is recommended.
DTC or 1st trip DTC of a malfunction is display ed in SELF-DIAGNOSTIC RESULTS mode of CONSULT-III.
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, engi ne 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 ca lled freeze frame data and displayed on CONSULT-III or
GST. The 1st trip freeze frame data can only be displa yed on the CONSULT-III screen, not on the GST. For
details, see EC-63, "CONSULT-III Function (ENGINE)"
.
Only one set of freeze frame data (either 1st trip freez e frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM me mory 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 (P riority: 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 tr ip 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 fr eeze frame data is stored in the ECM memory and freeze
Priority Items
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
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![INFINITI QX56 2009 Factory Workshop Manual
FUEL PRESSUREEC-487
< ON-VEHICLE MAINTENANCE > [VK56DE]
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FUEL PRESSURE
Fuel Pressure CheckINFOID:0000000003771746
FUEL PRESSURE RELEASE
With CON INFINITI QX56 2009 Factory Workshop Manual
FUEL PRESSUREEC-487
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Fuel Pressure CheckINFOID:0000000003771746
FUEL PRESSURE RELEASE
With CON](/img/42/57031/w960_57031-1813.png)
FUEL PRESSUREEC-487
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Fuel Pressure CheckINFOID:0000000003771746
FUEL PRESSURE RELEASE
With CONSULT-IIl
1. Turn ignition switch ON.
2. Perform “FUEL PRESSURE RELEASE” in
“WORK SUPPORT” mode with CONSULT-IIl.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
Without CONSULT-IIl
1. Remove fuel pump fuse located in IPDM E/R.
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel pressure.
4. Turn ignition switch OFF.
5. Reinstall fuel pump fuse after servicing fuel system.
FUEL PRESSURE CHECK
CAUTION:
Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.
Be careful not to scratch or get the fuel hose conn ection area dirty when servicing, so that the quick
connector o-ring maintains sealability.
Use Fuel Pressure Gauge Kit J-44321 and Fuel Pr essure Adapter J-44321-6 to check fuel pressure.
Do not perform fuel pressure check with electrical system operating (i.e. lights, rear defog, A/C, etc.).
Fuel pressure gauge may indicate false readings du e to varying engine loads and changes in mani-
fold vacuum.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel pres-
sure cannot be completely released because JA 60 models do not have fuel return system.
1. Release fuel pressure to zero. Refer to "FUEL PRESSURE RELEASE".
2. Remove engine cover.
3. Remove fuel hose using Quick Connector Release J-45488. Refer to EM-40
.
Do not twist or kink fuel hose because it is plastic hose.
Do not remove fuel hose from quick connector.
Keep fuel hose connections clean.
4. Install Fuel Pressure Adapter J-44321-6 and Fuel Pressure Gauge (from kit J-44321) as shown in figure.
Do not distort or bend fuel rail tube when installing fuel pres-sure gauge adapter.
When reconnecting fuel hose, check the original fuel hose for damage and abnormality.
5. Turn ignition switch ON (reactivate fuel pump), and check for fuel leakage.
6. Start engine and check for fuel leakage.
7. Read the indication of fuel pressure gauge. During fuel pressure check, check for fuel leakage from fuel
connection every 3 minutes.
BBIA0380E
BBIA0390E
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EM-4
< PRECAUTION >
PRECAUTIONS
5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of a ll control units using CONSULT-III.
Precaution for Drain Engine CoolantINFOID:0000000005885850
Drain engine coolant when engine is cooled.
Precaution for Disconnecting Fuel PipingINFOID:0000000005885851
• Before starting work, make sure no fire or spark producing items are in the work area.
• Release fuel pressure before disconnecting and disassembly.
• After disconnecting pipes, plug openings to stop fuel leakage.
Precaution for Removal and DisassemblyINFOID:0000000005885852
• When instructed to use special service tools, use the s pecified tools. Always be careful to work safely, avoid
forceful or uninstructed operations.
• Exercise maximum care to avoid damage to mating or sliding surfaces.
• Cover openings of engine system with tape or the equivalent, if necessary, to seal out foreign materials.
• Mark and arrange disassembly parts in an organi zed way for easy troubleshooting and assembly.
• When loosening nuts and bolts, as a basic rule, start with the one furthest outside, then the one diagonally opposite, and so on. If the order of loosening is specified, do exactly as specified. Power tools may be used
where noted in the step.
Precaution for Inspection, Repair and ReplacementINFOID:0000000005885853
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precaution for Assembly and InstallationINFOID:0000000005885854
• Use torque wrench to tighten bolts or nuts to specification.
• When tightening nuts and bolts, as a basic rule, equally tighten in several different steps starting with theones in center, then ones on inside and outside diagonally in this order. If the order of tightening is specified,
do exactly as specified.
• Replace with new gasket, packing, oil seal or O-ring.
• Thoroughly wash, clean, and air-blow each part. Carefully check engine oil or engine coolant passages for any restriction and blockage.
• Avoid damaging sliding or mating surfaces. Completely remove foreign materials such as cloth lint or dust. Before assembly, oil sliding surfaces well.
• Release air within route when refilling after draining engine coolant.
• Before starting engine, apply fuel pressure to fuel lines with turning ignition switch ON (with engine stopped). Then make sure that there are no leaks at fuel line connections.
• After repairing, start engine and increase engine s peed to check engine coolant, fuel, oil, and exhaust sys-
tems for leakage.
Parts Requiring Angular TighteningINFOID:0000000005885855
• For final tightening of the following engine parts use Tool:
- Cylinder head bolts
- Main bearing cap bolts
- Connecting rod cap bolts
- Crankshaft pulley bolt (No angle wrench is required as the bolt flange is provided with notches for angle tightening)
• Do not use a torque value for final tightening.
• The torque value for these parts are for a preliminary step.
• Ensure thread and seat surfaces are clean and lightly coated with engine oil. Tool number : KV10112100 (BT-8653-A)
Revision: December 20092009 QX56