battery INFINITI QX56 2008 Factory Service Manual
[x] Cancel search | Manufacturer: INFINITI, Model Year: 2008, Model line: QX56, Model: INFINITI QX56 2008Pages: 4083, PDF Size: 81.73 MB
Page 1589 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-290
< COMPONENT DIAGNOSIS >[VK56DE]
P0603 ECM POWER SUPPLY
3. Check voltage between ECM terminal 121 and ground with
CONSULT-III or tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.DETECT MALFUNCTI INFINITI QX56 2008 Factory Service Manual EC-290
< COMPONENT DIAGNOSIS >[VK56DE]
P0603 ECM POWER SUPPLY
3. Check voltage between ECM terminal 121 and ground with
CONSULT-III or tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.DETECT MALFUNCTI](/img/42/57030/w960_57030-1588.png)
EC-290
< COMPONENT DIAGNOSIS >[VK56DE]
P0603 ECM POWER SUPPLY
3. Check voltage between ECM terminal 121 and ground with
CONSULT-III or tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
• IPDM E/R connector E121
• 20A fuse
• Harness for open or short between ECM and battery
>> Repair or replace harness or connectors.
3.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness or connectors.
4.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-III
1. Turn ignition switch ON.
2. Select “SELF DIAG RESULTS” mode with CONSULT-III.
3. Touch “ERASE”.
4. Perform DTC Confirmation Procedure.
See EC-289, "
DTC Logic".
5. Is the 1st trip DTC P0603 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-289, "
DTC Logic".
4. Is the 1st trip DTC P0603 displayed again?
Ye s o r N o
Ye s > > G O T O 5 .
No >> INSPECTION END
5.REPLACE ECM
1. Replace ECM.
2. Perform initialization of IVIS(NATS) system and registration of all IVIS(NATS) ignition key IDs. Refer to SEC-8, "
ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement".
3. Perform EC-17, "
VIN Registration".
4. Perform EC-18, "
Accelerator Pedal Released Position Learning".
5. Perform EC-18, "
Throttle Valve Closed Position Learning".
6. Perform EC-18, "
Idle Air Volume Learning".
>> INSPECTION END
Voltage: Battery voltage
MBIB0026E
Revision: March 2010
2008 QX56
Page 1592 of 4083
![INFINITI QX56 2008 Factory Service Manual P0643 SENSOR POWER SUPPLYEC-293
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0643 SENSOR POWER SUPPLY
On Board Diagnosis LogicINFOID:0000000001351684
This self-diagnosis has the o INFINITI QX56 2008 Factory Service Manual P0643 SENSOR POWER SUPPLYEC-293
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0643 SENSOR POWER SUPPLY
On Board Diagnosis LogicINFOID:0000000001351684
This self-diagnosis has the o](/img/42/57030/w960_57030-1591.png)
P0643 SENSOR POWER SUPPLYEC-293
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0643 SENSOR POWER SUPPLY
On Board Diagnosis LogicINFOID:0000000001351684
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:0000000001351685
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 10V at idle.
WITH CONSULT-III
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-293, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351687
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-86, "
Ground Inspection".
OK or NG
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0643
0643 Sensor power supply circuit
short ECM detects a voltage of power source
for sensor is excessively low or high. • Harness or connectors
(APP sensor 1 circuit is shorted.)
(PSP sensor circuit is shorted.)
(Battery current sensor circuit is shorted.)
(Refrigerant pressure se nsor circuit is short-
ed.)
(EVAP control system pressure sensor circuit
is shorted.)
• Accelerator pedal position sensor
• Power steering pressure sensor
• Refrigerant pressure sensor
• EVAP control system pressure sensor
Engine operation 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
Revision: March 2010 2008 QX56
Page 1593 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-294
< COMPONENT DIAGNOSIS >[VK56DE]
P0643 SENSOR POWER SUPPLY
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal po INFINITI QX56 2008 Factory Service Manual EC-294
< COMPONENT DIAGNOSIS >[VK56DE]
P0643 SENSOR POWER SUPPLY
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal po](/img/42/57030/w960_57030-1592.png)
EC-294
< COMPONENT DIAGNOSIS >[VK56DE]
P0643 SENSOR POWER SUPPLY
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 5.
NG >> GO TO 3.
3.CHECK SENSOR POWER SUPPLY CIRCUITS
Check harness for short to power and short to ground, between the following terminals
OK or NG
OK >> GO TO 4.
NG >> Repair short to ground or short to power in harness or connectors.
4.CHECK COMPONENTS
Check the following.
• EVAP control system pressure sensor (Refer to EC-253, "
Component Inspection".)
• Power steering pressure sensor (Refer to EC-288, "
Component Inspection".)
• Battery current sensor (Refer to EC-318, "
Component Inspection".)
• Refrigerant pressure sensor
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning components.
5.CHECK ACCELERATOR PEDAL POSITION SENSOR
Refer to EC-384, "
Component Inspection".
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
BBIA0361E
Voltage: Approximately 5V
JMBIA0601ZZ
ECM terminal Sensor terminal Reference Wiring Diagram
48 EVAP control system pressure sensor terminal 3
EC-439, "
Wiring Diagram - ENGINE
CONTROL SYSTEM -"
49Refrigerant pressure sensor terminal 1
Battery current sensor terminal 1
68 Power steering pressure sensor terminal 1
90 APP sensor terminal 7
Revision: March 2010 2008 QX56
Page 1596 of 4083
![INFINITI QX56 2008 Factory Service Manual P0850 PNP SWITCHEC-297
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Check voltage between ECM terminal 102 (PNP signal) and
ground under the following conditions.
3. If NG, go t INFINITI QX56 2008 Factory Service Manual P0850 PNP SWITCHEC-297
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Check voltage between ECM terminal 102 (PNP signal) and
ground under the following conditions.
3. If NG, go t](/img/42/57030/w960_57030-1595.png)
P0850 PNP SWITCHEC-297
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Check voltage between ECM terminal 102 (PNP signal) and
ground under the following conditions.
3. If NG, go to EC-297, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001351694
1.CHECK DTC WITH TCM
Refer to TM-30, "
OBD-II Diagnostic Trouble Code (DTC)".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2.CHECK STARTING SYSTEM
Turn ignition switch OFF, then turn it to START.
Does starter motor operate?
Ye s o r N o
Yes >> GO TO 3.
No >> Refer to STR-17
.
3.CHECK PNP INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch OFF.
2. Disconnect A/T assembly harness connector.
3. Disconnect combination meter harness connector.
4. Check harness continuity between A/T assembly terminal 9 and combination meter terminal 8. Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors F14, E5
• Harness connectors E152, M31
• Harness for open or short between A/T assembly and combination meter
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK PNP INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 102 and combination meter terminal 7. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
Condition (Gear position) Voltage V (Known-good data)
P or N position Approx. 0
Except the above position BATTERY VOLTAGE
(11 - 14V)
MBIB0043E
Continuity should exist.
Continuity should exist.
Revision: March 2010 2008 QX56
Page 1599 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-300
< COMPONENT DIAGNOSIS >[VK56DE]
P1140, P1145 IVT CONTROL POSITION SENSOR
Refer to EC-86, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK INTAKE INFINITI QX56 2008 Factory Service Manual EC-300
< COMPONENT DIAGNOSIS >[VK56DE]
P1140, P1145 IVT CONTROL POSITION SENSOR
Refer to EC-86, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK INTAKE](/img/42/57030/w960_57030-1598.png)
EC-300
< COMPONENT DIAGNOSIS >[VK56DE]
P1140, P1145 IVT CONTROL POSITION SENSOR
Refer to EC-86, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK INTAKE VALVE TIMING CONTROL PO SITION SENSOR POWER SUPPLY CIRCUIT
1. Disconnect intake valve timing control position sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between intake valve timing control position sen- sor terminal 3 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E2, F32
• Harness for open or short between intake valve timing control position sensor and IPDM E/R
• Harness for open or short between intake valve timing control position sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK INTAKE VALVE TIMING CONTROL POSI TION SENSOR GROUND CIRCUIT FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between intake valve timing control position sensor terminal 1 and ground.
Refer to Wiring Diagram.
BBIA0354E
1. Intake valve timing control position
sensor (bank 2) 2. Intake valve timing control solenoid
valve (bank 2) 3. Drive belt
4. Radiator hose 5. Intake valve timing control solenoid
valve (bank 1) 6. Intake valve timing control position
sensor (bank 1)
Voltage: Battery voltage
BBIA0771E
SEF509Y
Revision: March 2010 2008 QX56
Page 1603 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-304
< COMPONENT DIAGNOSIS >[VK56DE]
P1211 TCS CONTROL UNIT
P1211 TCS CONTROL UNIT
DescriptionINFOID:0000000001351704
The malfunction information related to TCS is trans
ferred through the CAN commu INFINITI QX56 2008 Factory Service Manual EC-304
< COMPONENT DIAGNOSIS >[VK56DE]
P1211 TCS CONTROL UNIT
P1211 TCS CONTROL UNIT
DescriptionINFOID:0000000001351704
The malfunction information related to TCS is trans
ferred through the CAN commu](/img/42/57030/w960_57030-1602.png)
EC-304
< COMPONENT DIAGNOSIS >[VK56DE]
P1211 TCS CONTROL UNIT
P1211 TCS CONTROL UNIT
DescriptionINFOID:0000000001351704
The malfunction information related to TCS is trans
ferred through the CAN communication line from “ABS
actuator and electric unit (control unit)” to ECM.
Be sure to erase the malfunction information such as DTC not only for “ABS actuator and electric unit
(control unit)” but also for ECM after TCS related repair.
On Board Diagn osis LogicINFOID:0000000001351705
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:0000000001351706
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
WITH CONSULT-III
1. Start engine and let it idle for at least 60 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-304, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351707
Go to BRC-24, "CONSULT-III Function (ABS)".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1211
1211 TCS control unit
ECM receives a malfunction information from
“ABS actuator electric
unit (control unit)” • ABS actuator and electric unit (control
unit)
• TCS related parts
Revision: March 2010 2008 QX56
Page 1604 of 4083
![INFINITI QX56 2008 Factory Service Manual P1212 TCS COMMUNICATION LINEEC-305
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P1212 TCS COMMUNICATION LINE
DescriptionINFOID:0000000001351708
NOTE:
•
If DTC P1212 is displayed INFINITI QX56 2008 Factory Service Manual P1212 TCS COMMUNICATION LINEEC-305
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P1212 TCS COMMUNICATION LINE
DescriptionINFOID:0000000001351708
NOTE:
•
If DTC P1212 is displayed](/img/42/57030/w960_57030-1603.png)
P1212 TCS COMMUNICATION LINEEC-305
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P1212 TCS COMMUNICATION LINE
DescriptionINFOID:0000000001351708
NOTE:
•
If DTC P1212 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-87
.
• If DTC P1212 is displayed with DTC U1010, first pe rform the trouble diagnosis for DTC U1010. Refer
to EC-88
.
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:0000000001351709
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:0000000001351710
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
WITH CONSULT-III
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-305, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351711
Go to BRC-24, "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: March 2010 2008 QX56
Page 1609 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-310
< COMPONENT DIAGNOSIS >[VK56DE]
P1225 TP SENSOR
P1225 TP SENSOR
Component DescriptionINFOID:0000000001351876
Electric throttle control actuator consists of throttle control motor,
throttle posi INFINITI QX56 2008 Factory Service Manual EC-310
< COMPONENT DIAGNOSIS >[VK56DE]
P1225 TP SENSOR
P1225 TP SENSOR
Component DescriptionINFOID:0000000001351876
Electric throttle control actuator consists of throttle control motor,
throttle posi](/img/42/57030/w960_57030-1608.png)
EC-310
< COMPONENT DIAGNOSIS >[VK56DE]
P1225 TP SENSOR
P1225 TP SENSOR
Component DescriptionINFOID:0000000001351876
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:0000000001351877
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000001351878
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 10V at idle.
WITH CONSULT-lll
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-310, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-lll” above.
Diagnosis ProcedureINFOID:0000000001351879
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
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: March 2010 2008 QX56
Page 1611 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-312
< COMPONENT DIAGNOSIS >[VK56DE]
P1226 TP SENSOR
P1226 TP SENSOR
Component DescriptionINFOID:0000000001351881
Electric throttle control actuator consists of throttle control motor,
throttle posi INFINITI QX56 2008 Factory Service Manual EC-312
< COMPONENT DIAGNOSIS >[VK56DE]
P1226 TP SENSOR
P1226 TP SENSOR
Component DescriptionINFOID:0000000001351881
Electric throttle control actuator consists of throttle control motor,
throttle posi](/img/42/57030/w960_57030-1610.png)
EC-312
< COMPONENT DIAGNOSIS >[VK56DE]
P1226 TP SENSOR
P1226 TP SENSOR
Component DescriptionINFOID:0000000001351881
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:0000000001351882
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000001351883
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 10V at idle.
WITH CONSULT-III
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-312, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351884
1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Turn ignition switch OFF.
2. Remove the intake air duct.
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)
Revision: March 2010 2008 QX56
Page 1613 of 4083
![INFINITI QX56 2008 Factory Service Manual EC-314
< COMPONENT DIAGNOSIS >[VK56DE]
P1421 COLD START CONTROL
P1421 COLD START CONTROL
DescriptionINFOID:0000000001351886
ECM controls ignition timing and engine idle speed when engine is started wi INFINITI QX56 2008 Factory Service Manual EC-314
< COMPONENT DIAGNOSIS >[VK56DE]
P1421 COLD START CONTROL
P1421 COLD START CONTROL
DescriptionINFOID:0000000001351886
ECM controls ignition timing and engine idle speed when engine is started wi](/img/42/57030/w960_57030-1612.png)
EC-314
< COMPONENT DIAGNOSIS >[VK56DE]
P1421 COLD START CONTROL
P1421 COLD START CONTROL
DescriptionINFOID:0000000001351886
ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.
On Board Diagn
osis LogicINFOID:0000000001351887
DTC Confirmation ProcedureINFOID:0000000001351888
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.
• If DTC P1421 is displayed with other DTC, firs t perform the trouble diagnosis for other DTC.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-IIl
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-IIl.
4. Check that the “COOLAN TEMP/S” indication is between 4 °C (39° 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-314, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-lII” above.
Diagnosis ProcedureINFOID:0000000001351889
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
3.CHECK FUEL INJECTION SYSTEM FUNCTION
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
prewarming up condition. • Lack of intake air volume
• Fuel injection system
•ECM
Revision: March 2010
2008 QX56