2005 INFINITI QX4 light

DTC P1124, P1126 THROTTLE CONTROL MOTOR RELAY
EC-405
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
DTC P1124, P1126 THROTTLE CONTROL MOTOR RELAYPFP:16119
Component DescriptionUBS00H7P
Power supply for the throttle control motor is provided to the ECM via throttle control motor relay. The throttle
control motor relay is ON/OFF controlled by the ECM. When the ignition switch is turned ON, the ECM sends
an ON signal to throttle control motor relay and battery voltage is provided to the ECM. When the ignition
switch is turned OFF, the ECM sends an OFF signal to throttle control motor relay and battery voltage is not
provided to the ECM.
CONSULT-II Reference Value in Data Monitor ModeUBS00H7Q
Specification data are reference values.
On Board Diagnosis LogicUBS00H7R
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MlL lights up.
DTC Confirmation ProcedureUBS00H7S
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.
PROCEDURE FOR DTC P1124
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V.
With CONSULT-II
1. Turn ignition switch ON and wait at least 1 second.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. If DTC is detected, go to EC-408, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
MONITOR ITEM CONDITION SPECIFICATION
THRTL RELAY

Ignition switch: ON ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1124
11 2 4Throttle control motor
relay circuit shortECM detect the throttle control motor
relay is stuck ON.

Harness or connectors
(Throttle control motor relay circuit is shorted)

Throttle control motor relay
P1126
11 2 6Throttle control motor
relay circuit openECM detects a voltage of power source
for throttle control motor is excessively
low.

Harness or connectors
(Throttle control motor relay circuit is open)

Throttle control motor relay
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) by the return
spring.
SEF 0 58 Y

EC-410Revision: October 2005
DTC P1128 THROTTLE CONTROL MOTOR
2005 QX56
DTC P1128 THROTTLE CONTROL MOTORPFP:16119
Component DescriptionUBS00H7V
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 LogicUBS00H7W
This self-diagnosis has the one trip detection logic.
FAIL -S AFE M OD E
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureUBS00H7X
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.
WITH CONSULT-II
1. Turn ignition switch ON and wait at least 2 seconds.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 5 seconds.
4. If DTC is detected, go to EC-412, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1128
11 2 8Throttle control motor
circuit shortECM 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) by the return
spring.
SEF 0 58 Y

EC-438Revision: October 2005
DTC P1211 TCS CONTROL UNIT
2005 QX56
DTC P1211 TCS CONTROL UNITPFP:47850
DescriptionUBS00H8L
The malfunction information related to TCS is transferred 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 Diagnosis LogicUBS00H8M
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 ProcedureUBS00H8N
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V 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 at least 60 seconds.
4. If 1st trip DTC is detected, go to EC-438, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureUBS00H8O
Go to BRC-11, "TROUBLE DIAGNOSIS" .
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1211
1211TCS control unitECM receives a malfunction information from
“ABS actuator electric unit (control unit)”

ABS actuator and electric unit (control
unit)

TCS related parts
SEF 0 58 Y

DTC P1212 TCS COMMUNICATION LINE
EC-439
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
DTC P1212 TCS COMMUNICATION LINEPFP:47850
DescriptionUBS00H8P
NOTE:
If DTC P1212 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC U1000,
U1001. Refer to EC-163, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .
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 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 Diagnosis LogicUBS00H8Q
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 ProcedureUBS00H8R
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V 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 at least 10 seconds.
4. If 1st trip DTC is detected, go to EC-439, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureUBS00H8S
Go to BRC-11, "TROUBLE DIAGNOSIS" .
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1212
1212TCS communication
lineECM can not receive the information
from “ABS actuator and electric unit (con-
trol unit)” continuously.

Harness or connectors
(The CAN communication line is open or
shorted.)

ABS actuator and electric unit (control unit)

Dead (Weak) battery
SEF 0 58 Y

EC-450Revision: October 2005
DTC P1225 TP SENSOR
2005 QX56
DTC P1225 TP SENSORPFP:16119
Component DescriptionUBS00H91
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 Diagnosis LogicUBS00H92
The MIL will not light up for this diagnosis.
DTC Confirmation ProcedureUBS00H93
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-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. If 1st trip DTC is detected, go to EC-451, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1225
1225Closed throttle position learning
performance problemClosed throttle position learning value is
excessively low.

Electric throttle control actuator
(TP sensor 1 and 2)
SEF 0 58 Y

EC-452Revision: October 2005
DTC P1226 TP SENSOR
2005 QX56
DTC P1226 TP SENSORPFP:16119
Component DescriptionUBS00H96
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 Diagnosis LogicUBS00H97
The MIL will not light up for this diagnosis.
DTC Confirmation ProcedureUBS00H98
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-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Repeat steps 3 and 4 for 32 times.
6. If 1st trip DTC is detected, go to EC-453, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1226
1226Closed throttle position learning
performance problemClosed throttle position learning is not performed
successfully, repeatedly.

Electric throttle control actuator
(TP sensor 1 and 2)
SEF 0 58 Y

EC-454Revision: October 2005
DTC P1229 SENSOR POWER SUPPLY
2005 QX56
DTC P1229 SENSOR POWER SUPPLYPFP:16119
On Board Diagnosis LogicUBS00H9B
This self-diagnosis has the one trip detection logic.
FAIL -S AFE M OD E
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureUBS00H9C
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-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-456, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1229
1229Sensor power supply circuit
shortECM 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.)
(Refrigerant pressure sensor circuit is
shorted.)
(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) by the return
spring.
SEF 0 58 Y

DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-531
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
PFP:14920
DescriptionUBS00HAT
SYSTEM DESCRIPTION
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.
This system controls flow rate of fuel vapor from the EVAP canister. The opening of the vapor by-pass pas-
sage in the EVAP canister purge volume control solenoid valve changes to control the flow rate. The EVAP
canister purge volume control solenoid valve repeats ON/OFF operation according to the signal sent from the
ECM. The opening of the valve varies for optimum engine control. The optimum value stored in the ECM is
determined by considering various engine conditions. When the engine is operating, the flow rate of fuel vapor
from the EVAP canister is regulated as the air flow changes.
COMPONENT DESCRIPTION
The EVAP canister purge volume control solenoid valve uses a ON/
OFF duty to control the flow rate of fuel vapor from the EVAP canis-
ter. The EVAP canister purge volume control solenoid valve is
moved by ON/OFF pulses from the ECM. The longer the ON pulse,
the greater the amount of fuel vapor that will flow through the valve.
CONSULT-II Reference Value in Data Monitor ModeUBS00HAU
Specification data are reference values.
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
1
EVAP canister
purge flow controlEVAP canister purge vol-
ume control solenoid valve Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
1
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Air fuel ratio (A/F) sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)
Fuel tank temperature sensor Fuel temperature in fuel tank
Wheel sensor*
2Vehicle speed
PBIB2057E
MONITOR ITEM CONDITION SPECIFICATION
PURG VOL C/V

Engine: After warming up

Air conditioner switch: OFF

Selector lever: P or N

No loadIdle
(Accelerator pedal: Not depressed
even slightly, after starting engine)0%
2,000 rpm —