2010 INFINITI QX56 air condition

P1212 TCS COMMUNICATION LINEEC-301
< COMPONENT DIAGNOSIS > [VK56DE]
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P1212 TCS COMMUNICATION LINE
DescriptionINFOID:0000000005149346
NOTE:
•
If DTC P1212 is displayed with DTC UXXXX, first perform the tr ouble diagnosis for DTC UXXXX.
• If DTC P1212 is displayed with DT C P0607, first perform the trouble diagnosis for DTC P0607. Refer
to EC-288
.
This CAN communication line is used to control the smooth engine operation during the TCS operation. Pulse
signals are exchanged between ECM and “ABS actuator and electric unit (control unit)”.
Be sure to erase the malf unction information such as DTC not onl y for “ABS actuator and electric unit
(control unit)” but also for ECM after TCS related repair.
On Board Diagnosis LogicINFOID:0000000005149347
Freeze frame data is not stored in the ECM for this self-diagnosis.
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000005149348
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5 V at idle.
1. Start engine and let it idle for at least 10 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-301, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149349
Go to BRC-23, "CONSULT-III Function (ABS)".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1212
1212 TCS communication line ECM can not receive the information from
“ABS actuator and electric unit (control
unit)” continuously. • Harness or connectors
(The CAN communication line is open or short-
ed.)
• ABS actuator and electric unit (control unit)
• Dead (Weak) battery
Revision: April 20092010 QX56

EC-306
< COMPONENT DIAGNOSIS >[VK56DE]
P1225 TP SENSOR
P1225 TP SENSOR
Component DescriptionINFOID:0000000005149354
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 the 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 the 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 Diagn osis LogicINFOID:0000000005149355
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000005149356
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 10 V at idle.
1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Check 1st trip DTC.
5. If 1st trip DTC is detected, go to EC-306, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149357
1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Turn ignition switch OFF.
2. Remove the intake air duct.
3. Check if foreign matter is caught between the throttle valve and the housing.
OK or NG
OK >> GO TO 2.
NG >> Remove the foreign matter and clean the electric throttle control actuator inside.
2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P1225
1225 Closed throttle position learning
performance Closed throttle position learning value is
excessively low. • Electric throttle control actuator
(TP sensor 1 and 2)
BBIA0364E
Revision: April 20092010 QX56

EC-308
< COMPONENT DIAGNOSIS >[VK56DE]
P1226 TP SENSOR
P1226 TP SENSOR
Component DescriptionINFOID:0000000005149358
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 the 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 the 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 Diagn osis LogicINFOID:0000000005149359
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000005149360
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 10 V at idle.
1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Repeat steps 2 and 3 for 32 times.
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to EC-308, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149361
1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Turn ignition switch OFF.
2. Remove the intake air duct.
3. Check if foreign matter is caught between the throttle valve and the housing.
OK or NG
OK >> GO TO 2.
NG >> Remove the foreign matter and clean the electric throttle control actuator inside.
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P1226
1226 Closed throttle position learning
performance Closed throttle position learning is not performed
successfully, repeatedly. • Electric throttle control actuator
(TP sensor 1 and 2)
BBIA0364E
Revision: April 20092010 QX56

EC-310
< COMPONENT DIAGNOSIS >[VK56DE]
P1421 COLD START CONTROL
P1421 COLD START CONTROL
DescriptionINFOID:0000000005149362
ECM controls ignition timing and engine idle speed when engine is started with pre-warming up condition.
This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.
On Board Diagn
osis LogicINFOID:0000000005149363
If DTC P1421 is displayed with ot her DTC, first perform the trouble diagnosis for other DTC.
DTC Confirmation ProcedureINFOID:0000000005149364
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 at idle.
WITH CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check that the “COOLAN TEMP/S” indication is between 5 °C (41° F) and 36 °C (97° F).
If “COOLAN TEMP/S” indication is within the specified value, go to the following step.
If “COOLANT TEMP/S” indication is out of the s pecified value, cool engine down or warm engine up and
go to step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-310, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000005149365
1.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-18, "
Idle Air Volume Learning".
Is Idle Air Volume Lear ning carried out successfully?
Ye s o r N o
Ye s > > G O T O 2 .
No >> Follow the instruction of Idle Air Volume Learning.
2.CHECK INTAKE SYSTEM
Check for the cause of intake air volume lacking. Refer to the following.
• Crushed intake air passage
• Intake air passage clogging
OK or NG
OK >> GO TO 3.
NG >> Repair or replace malfunctioning part
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P1421
1421 Cold start emission reduction
strategy monitoring ECM does not control ignition timing and engine
idle speed properly when engine is started with
pre-warming up condition. • Lack of intake air volume
• Fuel injection system
•ECM
Revision: April 20092010 QX56

P1564 ICC STEERING SWITCHEC-329
< COMPONENT DIAGNOSIS > [VK56DE]
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Refer to
EC-85, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK ICC STEERING SWITCH CIRCUIT
With CONSULT-III
1. Turn ignition switch ON.
2. Select “MAIN SW”, “CANCEL SW ”, “RESUME/ACC SW”, “SET SW” and “DIST SW” in “DATA MONITOR”
mode with CONSULT-III.
3. Check each item indication under the following conditions.
Without CONSULT-III
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 99 and ground with press- ing each button.
OK or NG
BBIA0354E
Switch Monitor item Condition Indication
MAIN switch MAIN SWPressed ON
Released OFF
CANCEL switch CANCEL SWPressed ON
Released OFF
RESUME/ACCELERATE
switch RESUME/ACC SWPressed ON
Released OFF
SET/COAST switch SET SW Pressed ON
Released OFF
DISTANCE switch DIST SW Pressed ON
Released OFF
Switch Condition Voltage [V]
MAIN switch Pressed
Approx. 0
Released Approx. 4.3
CANCEL switch Pressed
Approx. 1.3
Released Approx. 4.3
RESUME/ACCELERATE
switch Pressed
Approx. 3.7
Released Approx. 4.3
SET/COAST switch Pressed
Approx. 3.0
Released Approx. 4.3
DISTANCE switch Pressed
Approx. 2.2
Released Approx. 4.3
PBIB0311E
Revision: April 20092010 QX56

P1564 ASCD STEERING SWITCHEC-333
< COMPONENT DIAGNOSIS > [VK56DE]
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Refer to
EC-85, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK ASCD STEERING SWITCH CIRCUIT
With CONSULT-III
1. Turn ignition switch ON.
2. Select “MAIN SW”, “CANCEL SW”, RESUME/ACC SW” and “SET SW” in “DATA MONITOR” mode with
CONSULT-III.
3. Check each item indication under the following conditions.
Without CONSULT-III
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 99 and ground with press- ing each button.
OK or NG
OK >> GO TO 8.
NG >> GO TO 3.
3.CHECK ASCD STEERING SWITCH GRO UND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
BBIA0354E
Switch Monitor item Condition Indication
MAIN switch MAIN SWPressed ON
Released OFF
CANCEL switch CANCEL SWPressed ON
Released OFF
RESUME/ACCELERATE
switch RESUME/ACC SWPressed ON
Released OFF
SET/COAST switch SET SW Pressed ON
Released OFF
Switch Condition Voltage [V]
MAIN switch Pressed
Approx. 0
Released Approx. 4
CANCEL switch Pressed
Approx. 1
Released Approx. 4
RESUME/ACCELERATE
switch Pressed Approx.
3
Released Approx. 4
SET/COAST switch Pressed
Approx. 2
Released Approx. 4
PBIB0311E
Revision: April 20092010 QX56

EC-346
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ASCD BRAKE SWITCH
Without CONSULT-III
Check voltage between ECM terminal 101 and ground under the following conditions.
OK or NG
OK >> GO TO 11.
NG >> GO TO 7.
3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) connector M4
• 10 A fuse (No. 15)
• Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 108 and ASCD brake switch terminal 2. Refer to Wiring Diagram.
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB1537E
BBIA0373E
Voltage: Battery voltage
PBIB0857E
Revision: April 20092010 QX56

EC-348
< COMPONENT DIAGNOSIS >[VK56DE]
P1572 ASCD BRAKE SWITCH
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
10.CHECK STOP LAMP SWITCH
Refer to EC-348, "
Component Inspection".
OK or NG
OK >> GO TO 11.
NG >> Replace stop lamp switch.
11 .CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000005149408
ASCD BRAKE SWITCH
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Check harness continuity between ASCD brake switch terminals
1 and 2 under the following conditions.
If NG, adjust ASCD brake switch installation, refer to BR-15,
"Inspection and Adjustment", and perform step 3 again.
STOP LAMP SWITCH
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check harness continuity between stop lamp switch terminals 1
and 2 under the following conditions.
If NG, adjust stop lamp switch installation, refer to BR-15,
"Inspection and Adjustment", and perform step 3 again.
ConditionContinuity
Brake pedal: Fully released Should exist.
Brake pedal: Slightly depressed Should not exist.
SEC023D
ConditionContinuity
Brake pedal: Fully released Should not exist.
Brake pedal: Slightly depressed Should exist.
PBIB2103E
Revision: April 20092010 QX56