2007 INFINITI QX56 DTC

EC-578
< SERVICE INFORMATION >
DTC P2135 TP SENSOR
1. Disconnect electric throttle control actuator (1) harness connec-
tor.
- Illustration shows the view with intake air duct removed.
2. Turn ignition switch ON.
3. Check voltage between electric throttle control actuator (1) ter-
minal 2 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 7.
NG >> GO TO 3.
3.CHECK THROTTLE POSITION SENSOR POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between electric throttle control actuator terminal 2 and ECM terminal 47.
Refer to Wiring Diagram.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit.
4.CHECK THROTTLE POSITION SENSOR POWER SUPPLY CIRCUIT-III
Check harness for short to power and short to ground, between the following terminals.
OK or NG
OK >> GO TO 5.
NG >> Repair short to ground or short to power in harness or connectors.
5.CHECK ACCELERATOR PEDAL POSITION SENSOR
Refer to EC-587, "
Component Inspection".
OK or NG
OK >> GO TO 11.
NG >> GO TO 6.
6.REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace the accelerator pedal assembly.
2. Perform EC-77, "
Accelerator Pedal Released Position Learning".
3. Perform EC-77, "
Throttle Valve Closed Position Learning".
4. Perform EC-78, "
Idle Air Volume Learning".
BBIA0371E
Voltage: Approximately 5V
PBIB2065E
Continuity should exist.
ECM terminal Sensor terminal Reference Wiring Diagram
47 Electric throttle control actuator terminal 2EC-576
91 APP sensor terminal 6EC-583

DTC P2135 TP SENSOR
EC-579
< SERVICE INFORMATION >
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>>INSPECTION END
7.CHECK THROTTLE POSITION SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between electric throttle control actuator terminal 4 and ECM terminal 66.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK THROTTLE POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 50 and electric throttle control actuator terminal 1, ECM
terminal 69 and electric throttle control actuator terminal 3.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK THROTTLE POSITION SENSOR
Refer to EC-579, "
Component Inspection".
OK or NG
OK >> GO TO 11.
NG >> GO TO 10.
10.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-77, "
Throttle Valve Closed Position Learning".
3. Perform EC-78, "
Idle Air Volume Learning".
>>INSPECTION END
11 .CHECK INTERMITTENT INCIDENT
Refer to EC-138
.
>>INSPECTION END
Component InspectionINFOID:0000000003532131
THROTTLE POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Perform EC-77, "
Throttle Valve Closed Position Learning".
3. Turn ignition switch ON.
4. Set selector lever to D position. Continuity should exist.
Continuity should exist.

EC-580
< SERVICE INFORMATION >
DTC P2135 TP SENSOR
5. Check voltage between ECM terminals 50 (TP sensor 1 signal),
69 (TP sensor 2 signal) and ground under the following condi-
tions.
6. If NG, replace electric throttle control actuator and go to the next
step.
7. Perform EC-77, "
Throttle Valve Closed Position Learning".
8. Perform EC-78, "
Idle Air Volume Learning".
Removal and InstallationINFOID:0000000003532132
ELECTRIC THROTTLE CONTROL ACTUATOR
Refer to EM-17.
Terminal Accelerator pedal Voltage
50
(Throttle position sensor 1)Fully released More than 0.36V
Fully depressed Less than 4.75V
69
(Throttle position sensor 2)Fully released Less than 4.75V
Fully depressed More than 0.36V
PBIB1530E

DTC P2138 APP SENSOR
EC-581
< SERVICE INFORMATION >
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DTC P2138 APP SENSOR
Component DescriptionINFOID:0000000003532133
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 position sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532134
Specification data are reference values.
*: Accelerator pedal position sensor 2 signal is converted by ECM internally. Thus, it differ from ECM terminal voltage.
On Board Diagnosis LogicINFOID:0000000003532135
This self-diagnosis has the one trip detection logic.
NOTE:
If DTC P2138 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to
EC-447
.
FA I L - S A F E M O D E
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
PBIB1741E
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SEN 1• Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.2 - 4.8V
ACCEL SEN 2*• Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.2 - 4.8V
CLSD THL POS• Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2138
2138Accelerator pedal position
sensor circuit range/per-
formanceRationally 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.

EC-582
< SERVICE INFORMATION >
DTC P2138 APP SENSOR
DTC Confirmation Procedure
INFOID:0000000003532136
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.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to EC-584, "
Diagnosis Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
SEF058Y

DTC P2138 APP SENSOR
EC-583
< SERVICE INFORMATION >
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Wiring DiagramINFOID:0000000003532137
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
BBWA1709E

EC-584
< SERVICE INFORMATION >
DTC P2138 APP SENSOR
Diagnosis Procedure
INFOID:0000000003532138
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-143, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
47 YSensor power supply
(TP sensor)[Ignition switch: ON]Approximately 5V
82 B/RSensor ground
(APP sensor 1)[Engine is running]
•Warm-up condition
• Idle speedApproximately 0V
83 G/WSensor ground
(APP sensor 2)[Engine is running]
•Warm-up condition
• Idle speedApproximately 0V
90 LSensor power supply
(APP sensor 1)[Ignition switch: ON]Approximately 5V
91 W/RSensor power supply
(APP sensor 2)[Ignition switch: ON]Approximately 5V
98 G/RAccelerator pedal position
sensor 2[Ignition switch: ON]
• Engine: Stopped
• Accelerator pedal: Fully released0.25 - 0.50V
[Ignition switch: ON]
• Engine: Stopped
• Accelerator pedal: Fully depressed2.0 - 2.5V
106 BR/WAccelerator pedal position
sensor 1[Ignition switch: ON]
• Engine: Stopped
• Accelerator pedal: Fully released0.5 - 1.0V
[Ignition switch: ON]
• Engine: Stopped
• Accelerator pedal: Fully depressed4.2 - 4.8V
BBIA0354E

DTC P2138 APP SENSOR
EC-585
< SERVICE INFORMATION >
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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-II 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 2 POWER SUPPLY CIRCUIT-I
1. Turn ignition switch ON.
2. Check voltage between APP sensor terminal 6 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 4.
4.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between APP sensor terminal 6 and ECM terminal 91.
Refer to Wiring Diagram.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit in harness or connectors.
5.CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT-III
Check harness for short to power and short to ground, between the following terminals
OK or NG
OK >> GO TO 6.
BBIA0361E
Voltage: Approximately 5V
PBIB2070E
Voltage: Approximately 5V
PBIB2069E
Continuity should exist.
ECM terminal Sensor terminal Reference Wiring Diagram
47 Electric throttle control actuator terminal 2EC-576
91 APP sensor terminal 6EC-583