2010 INFINITI QX56 sensor

P1574 ASCD VEHICLE SPEED SENSOREC-351
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P1574 ASCD VEHICLE SPEED SENSOR
Component DescriptionINFOID:0000000005149413
The ECM receives two vehicle speed sensor signals via
CAN communication line. One is sent from combina-
tion meter and the other is from TCM (Transmission control module). The ECM uses these signals for ASCD
control. Refer to EC-33, "
System Description" for ASCD functions.
On Board Diagnosis LogicINFOID:0000000005149414
• This self-diagnosis has the one trip detection logic.
• The MIL will not light up for this self-diagnosis.
NOTE:
• If DTC P1574 is displayed with DTC UXXXX, first perform the tr ouble diagnosis for DTC UXXXX.
• If DTC P1574 is displayed with DT C P0500, first perform the trouble diagnosis for DTC P0500. Refer
to EC-275, "
On Board Diagnosis Logic".
• If DTC P1574 is displayed with DT C P0605, first perform the trouble diagnosis for DTC P0605. Refer
to EC-286, "
On Board Diagnosis Logic".
• If DTC P1574 is displayed with DT C P0607, first perform the trouble diagnosis for DTC P0607. Refer
to EC-288, "
On Board Diagnosis Logic".
DTC Confirmation ProcedureINFOID:0000000005149415
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Step 3 may be conducted with the dr ive wheels lifted in the shop or by driving the vehicle. If a road test
is expected to be easier, it is unnecessary to lift the vehicle.
1. Start engine (VDC switch OFF).
2. Drive the vehicle at more than 40 km/h (25 MPH).
3. Check DTC.
4. If DTC is detected, go to EC-351, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149416
1.CHECK DTC WITH TCM
Check DTC with TCM. Refer to TM-30, "
OBD-II Diagnostic Trouble Code (DTC)".
OK or NG
OK >> GO TO 2.
NG >> Perform trouble shooting relevant to DTC indicated.
2.CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Refer to BRC-23, "
CONSULT-III Function (ABS)".
DTC No. Trouble Diagnosis
Name DTC Detecting Condit
ion Possible Cause
P1574
1574 ASCD vehicle speed
sensor ECM detects a difference between two vehicle
speed signals is out of the specified range. • Harness or connectors
(The CAN communication line is open or
shorted.)
• Combination meter
• ABS actuator and electric unit (control unit)
• Wheel sensor
•TCM
•ECM
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EC-352
< COMPONENT DIAGNOSIS >[VK56DE]
P1574 ASCD VEHICLE SPEED SENSOR
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3.CHECK COMBINATION METER FUNCTION
Check combination meter function.
Refer to MWI-5
.
>> INSPECTION END
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P2101 ELECTRIC THROTTLE CONTROL FUNCTIONEC-359
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P2101 ELECTRIC THROTTLE CONTROL FUNCTION
DescriptionINFOID:0000000005149426
NOTE:
If DTC P2101 is displayed with DTC P2100 or 2119,
first perform the trouble diagnosis for DTC P2100
or P2119. Refer to EC-356
or EC-365.
Electric throttle control actuator consists of throttle control mo tor, 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 motor to make the throttle valve opening angle properly in
response to driving condition.
On Board Diagnosis LogicINFOID:0000000005149427
This self-diagnosis has the on e trip detection logic.
FA I L - S A F E M O D E
When the malfunction is detected, ECM ent ers fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000005149428
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11 V 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-359, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149429
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: April 20092010 QX56

P2118 THROTTLE CONTROL MOTOREC-363
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P2118 THROTTLE CONTROL MOTOR
Component DescriptionINFOID:0000000005149431
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 motor to make the throttle valve opening angle properly in
response to driving condition.
On Board Diagnosis LogicINFOID:0000000005149432
This self-diagnosis has the on e trip detection logic.
FA I L - S A F E M O D E
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000005149433
1. If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting 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-363, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149434
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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P2119 ELECTRIC THROTTLE CONTROL ACTUATOREC-365
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P2119 ELECTRIC THROTTLE CONTROL ACTUATOR
Component DescriptionINFOID:0000000005149436
Electric throttle control actuator consists of throttle control mo
tor, 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 valve 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 Diagnosis LogicINFOID:0000000005149437
This self-diagnosis has one trip detection logic.
FA I L - S A F E M O D E
When the malfunction is detected, ECM ent ers fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000005149438
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 procedure before conducting the next step
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch 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-366, "
Diagnosis Procedure".
PROCEDURE FOR MALFUNCTION C
DTC No. Trouble diagnosis name DTC detecting conditionPossible 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: April 20092010 QX56

P2122, P2123 APP SENSOREC-367
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P2122, P2123 APP SENSOR
Component DescriptionINFOID:0000000005149440
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 position sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
On Board Diagnosis LogicINFOID:0000000005149441
These self-diagnoses have the on e trip detection logic.
NOTE:
If DTC P2122 or P2123 is displayed with DTC P0643, first perform the tro\
uble diagnosis for DTC P0643.
Refer to EC-289
.
FA I L - S A F E M O D E
When the malfunction is detected, ECM ent ers fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000005149442
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8 V at idle.
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-367, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149443
1.CHECK GROUND CONNECTIONS
PBIB1741E
DTC No. Trouble diagnosis name DTC detecting conditionPossible 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 voltage 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.
Revision: April 20092010 QX56

EC-368
< COMPONENT DIAGNOSIS >[VK56DE]
P2122, P2123 APP SENSOR
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.
2.CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal position (APP) sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between APP sensor terminal 7 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
3.CHECK APP SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 82 and APP sensor terminal 1. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 106 and APP sensor terminal 2. Refer to Wiring Diagram.
BBIA0354E
BBIA0361E
Voltage: Approximately 5 V
JMBIA0601ZZ
Continuity should exist.
Revision: April 20092010 QX56

P2122, P2123 APP SENSOREC-369
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2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK APP SENSOR
Refer to EC-369, "
Component Inspection".
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace the accelerator pedal assembly.
2. Perform EC-18, "
Accelerator Pedal Released Position Learning".
3. Perform EC-18, "
Throttle Valve Closed Position Learning".
4. Perform EC-18, "
Idle Air Volume Learning".
>> INSPECTION END
7.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000005149444
ACCELERATOR PEDAL POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch ON.
3. Check voltage between ECM terminals 106 (APP sensor 1 sig-
nal), 98 (APP sensor 2 signal) and ground under the following
conditions.
4. If NG, replace accelerator pedal assembly and go to next step.
5. Perform EC-18, "
Accelerator Pedal Released Position Learning".
6. Perform EC-18, "
Throttle Valve Closed Position Learning".
7. Perform EC-18, "
Idle Air Volume Learning".
Continuity should exist.
Terminal
Accelerator pedal Voltage
106
(Accelerator pedal position
sensor 1) Fully released
0.5 - 1.0 V
Fully depressed 4.2 - 4.8 V
98
(Accelerator pedal position
sensor 2) Fully released
0.25 - 0.5 V
Fully depressed 2.0 - 2.5 V
MBIB0023E
Revision: April 20092010 QX56