fuel INFINITI QX56 2010 Factory Service Manual

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

P1421 COLD START CONTROLEC-311
< COMPONENT DIAGNOSIS > [VK56DE]
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3.CHECK FUEL INJECTION SYSTEM FUNCTION
Perform EC-172, "
DTC Confirmation Procedure" in DTC P0171, P0174 FUEL INJECTION SYSTEM FUNC-
TION.
OK or NG
OK >> GO TO 4.
NG >> Go to EC-173, "
Diagnosis Procedure".
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-310, "
DTC Confirmation Procedure".
5. Is the 1st trip DTC P1421 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-310, "
DTC Confirmation Procedure".
4. Is the 1st trip DTC P1421 displayed again?
Ye s o r N o
Yes >> GO TO 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-9, "
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
Revision: April 20092010 QX56

EC-312
< COMPONENT DIAGNOSIS >[VK56DE]
P1550 BATTERY CURRENT SENSOR
P1550 BATTERY CURRENT SENSOR
Component DescriptionINFOID:0000000005149366
The power generation voltage variable control enables fuel con-
sumption to be decreased by reducing the engine load which is
caused by the power generation of the generator. The battery cur-
rent sensor (1) is installed to the battery cable at the negative termi-
nal. The sensor measures the charging/discharging current of the
battery. Based on the sensor signal, ECM judges whether or not the
power generation voltage variable control is performed. When per-
forming the power generation voltage variable control, ECM calcu-
lates the target power generation voltage based on the sensor
signal. And ECM sends the calculated value as the power genera-
tion command value to IPDM E/R. For the details of the power gen-
eration voltage variable control, refer to
CHG-7, "
System
Description".
: Vehicle front
CAUTION:
Do not connect the electrical compon ent or the ground wire directly to the battery terminal. The con-
nection causes the malfunction of th e power generation voltage variable control, and then the battery
discharge may occur.
On Board Diagn osis LogicINFOID:0000000005149367
The MIL will not light up for this self-diagnosis.
NOTE:
If DTC P1550 is displayed with DTC P0643, first pe rform the trouble diagnosis for DTC P0643. Refer to
EC-289
.
DTC Confirmation ProcedureINFOID:0000000005149368
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 wait at least 10 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-312, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149369
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body.
BBIA0744E
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P1550
1550 Battery current sensor circuit
range/performance The output voltage of the battery current
sensor remains within the specified
range while engine is running. • Harness or connectors
(The sensor circuit is open or shorted.)
• Battery current sensor
Revision: April 20092010 QX56

EC-316
< COMPONENT DIAGNOSIS >[VK56DE]
P1551, P1552 BATTERY CURRENT SENSOR
P1551, P1552 BATTERY CURRENT SENSOR
Component DescriptionINFOID:0000000005149371
The power generation voltage variable control enables fuel con-
sumption to be decreased by reducing the engine load which is
caused by the power generation of the generator. The battery cur-
rent sensor (1) is installed to the battery cable at the negative termi-
nal. The sensor measures the charging/discharging current of the
battery. Based on the sensor signal, ECM judges whether or not the
power generation voltage variable control is performed. When per-
forming the power generation voltage variable control, ECM calcu-
lates the target power generation voltage based on the sensor
signal. And ECM sends the calculated value as the power genera-
tion command value to IPDM E/R. For the details of the power gen-
eration voltage variable control, refer to
CHG-7, "
System
Description".
: Vehicle front
CAUTION:
Do not connect the electrical compon ent or the ground wire directly to the battery terminal. The con-
nection causes the malfunction of th e power generation voltage variable control, and then the battery
discharge may occur.
On Board Diagn osis LogicINFOID:0000000005149372
The MIL will not light up for these self-diagnoses.
NOTE:
If DTC P1551 or P1552 is displayed with DTC P0643, first perform the tro\
ubl e diagnosis for DTC P0643.
Refer to EC-289, "
On Board Diagnosis Logic".
DTC Confirmation ProcedureINFOID:0000000005149373
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 pro cedure, confirm that battery voltage is more than 8 V with ignition
switch ON
1. Turn ignition switch ON.
2. Wait at least 10 seconds.
3. Check 1st trip DTC.
4. If 1st trip DTC is detected, go to EC-316, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149374
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body.
BBIA0744E
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P1551
1551 Battery current sensor circuit
low input An excessively low voltage from the sensor
is sent to ECM.
• Harness or connectors
(The sensor circuit is open or shorted.)
• Battery current sensor
P1552
1552 Battery current sensor circuit
high input An excessively high voltage from the sensor
is sent to ECM.
Revision: April 20092010 QX56

EC-320
< COMPONENT DIAGNOSIS >[VK56DE]
P1553 BATTERY CURRENT SENSOR
P1553 BATTERY CURRENT SENSOR
Component DescriptionINFOID:0000000005149376
The power generation voltage variable control enables fuel con-
sumption to be decreased by reducing the engine load which is
caused by the power generation of the generator. The battery cur-
rent sensor (1) is installed to the battery cable at the negative termi-
nal. The sensor measures the charging/discharging current of the
battery. Based on the sensor signal, ECM judges whether or not the
power generation voltage variable control is performed. When per-
forming the power generation voltage variable control, ECM calcu-
lates the target power generation voltage based on the sensor
signal. And ECM sends the calculated value as the power genera-
tion command value to IPDM E/R. For the details of the power gen-
eration voltage variable control, refer to
CHG-7, "
System
Description".
: Vehicle front
CAUTION:
Do not connect the electrical compon ent or the ground wire directly to the battery terminal. The con-
nection causes the malfunction of th e power generation voltage variable control, and then the battery
discharge may occur.
On Board Diagn osis LogicINFOID:0000000005149377
The MIL will not light up for this self-diagnosis.
NOTE:
If DTC P1553 is displayed with DTC P0643, first pe rform the trouble diagnosis for DTC P0643. Refer to
EC-289
.
DTC Confirmation ProcedureINFOID:0000000005149378
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 wait at least 10 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-320, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149379
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body.
BBIA0744E
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P1553
1553 Battery current sensor performance The signal voltage transmitted from the
sensor to ECM is higher than the amount
of the maximum power generation. • Harness or connectors
(The sensor circuit is open or shorted.)
• Battery current sensor
Revision: April 20092010 QX56

EC-324
< COMPONENT DIAGNOSIS >[VK56DE]
P1554 BATTERY CURRENT SENSOR
P1554 BATTERY CURRENT SENSOR
Component DescriptionINFOID:0000000005149381
The power generation voltage variable control enables fuel con-
sumption to be decreased by reducing the engine load which is
caused by the power generation of the generator. The battery cur-
rent sensor (1) is installed to the battery cable at the negative termi-
nal. The sensor measures the charging/discharging current of the
battery. Based on the sensor signal, ECM judges whether or not the
power generation voltage variable control is performed. When per-
forming the power generation voltage variable control, ECM calcu-
lates the target power generation voltage based on the sensor
signal. And ECM sends the calculated value as the power genera-
tion command value to IPDM E/R. For the details of the power gen-
eration voltage variable control, refer to
CHG-7, "
System
Description".
: Vehicle front
CAUTION:
Do not connect the electrical compon ent or the ground wire directly to the battery terminal. The con-
nection causes the malfunction of th e power generation voltage variable control, and then the battery
discharge may occur.
On Board Diagn osis LogicINFOID:0000000005149382
The MIL will not light up for this self-diagnosis.
NOTE:
If DTC P1554 is displayed with DTC P0643, first pe rform the trouble diagnosis for DTC P0643. Refer to
EC-289, "
On Board Diagnosis Logic".
Overall Function CheckINFOID:0000000005149383
Use this procedure to check the overall function of the battery current sensor circuit. During this check, a 1st
trip DTC might not be confirmed.
TESTING CONDITION:
• Before performing the following procedure, confirm th at battery voltage is more than 12.8 V at idle.
• Before performing the following procedure, confi rm that all load switches and A/C switch are turned
OFF.
WITH CONSULT-III
1. Start engine and let it idle.
2. Select “BAT CUR SEN” in “DATA MONITOR” mode with CONSULT-III.
3. Check “BAT CUR SEN” indication for 10 seconds.
“BAT CUR SEN” should be above 2,300 mV at least once.
4. If NG, go to EC-325, "
Diagnosis Procedure".
WITH GST
1. Start engine and let it idle.
BBIA0744E
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P1554
1554 Battery current sensor performance The output voltage of the battery current
sensor is lower than the specified value
while the battery voltage is high enough. • Harness or connectors
(The sensor circuit is open or shorted.)
• Battery current sensor
Revision: April 20092010 QX56

P2119 ELECTRIC THROTTLE CONTROL ACTUATOREC-365
< COMPONENT DIAGNOSIS > [VK56DE]
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EC
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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
< COMPONENT DIAGNOSIS > [VK56DE]
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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-370
< COMPONENT DIAGNOSIS >[VK56DE]
P2127, P2128 APP SENSOR
P2127, P2128 APP SENSOR
Component DescriptionINFOID:0000000005149445
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.
On Board Diagn
osis LogicINFOID:0000000005149446
These self-diagnoses have the one trip detection logic.
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.
DTC Confirmation ProcedureINFOID:0000000005149447
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-370, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149448
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 conditionPossible 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: April 20092010 QX56

EC-378
< COMPONENT DIAGNOSIS >[VK56DE]
P2138 APP SENSOR
P2138 APP SENSOR
Component DescriptionINFOID:0000000005149455
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.
On Board Diagn
osis LogicINFOID:0000000005149456
This self-diagnosis has the one trip detection logic.
NOTE:
If DTC P2138 is displayed with DTC P0643, first pe rform the trouble 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 enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000005149457
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-379, "
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 sign
als 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: April 20092010 QX56