2009 INFINITI QX56 sensor

EC-302
< COMPONENT DIAGNOSIS >[VK56DE]
P1225 TP SENSOR
P1225 TP SENSOR
Component DescriptionINFOID:0000000003771593
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 t he 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:0000000003771594
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000003771595
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V 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-302, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771596
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 condition Possible 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: December 20092009 QX56

P1225 TP SENSOREC-303
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1. Replace the electric throttle control actuator.
2. Perform
EC-18, "Throttle Valve Closed Position Learning"
.
3. Perform EC-18, "Idle Air Volume Learning"
.
>> INSPECTION END
Revision: December 20092009 QX56

EC-304
< COMPONENT DIAGNOSIS >[VK56DE]
P1226 TP SENSOR
P1226 TP SENSOR
Component DescriptionINFOID:0000000003771597
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 t he 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:0000000003771598
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000003771599
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V 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-304, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771600
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 condition Possible 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: December 20092009 QX56

P1226 TP SENSOREC-305
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2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-18, "Throttle Valve Closed Position Learning"
.
3. Perform EC-18, "Idle Air Volume Learning"
.
>> INSPECTION END
Revision: December 20092009 QX56

EC-308
< COMPONENT DIAGNOSIS >[VK56DE]
P1550 BATTERY CURRENT SENSOR
P1550 BATTERY CURRENT SENSOR
Component DescriptionINFOID:0000000003771605
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:0000000003771606
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-285
.
DTC Confirmation ProcedureINFOID:0000000003771607
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V 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-308, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771608
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 condition Possible 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: December 20092009 QX56

P1550 BATTERY CURRENT SENSOREC-309
< 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 BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT
1. Disconnect battery current sensor (1) harness connector.
2. Turn ignition switch ON. : Vehicle front
3. Check voltage between battery current sensor terminal 1 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E5, F14
 Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between battery cu rrent sensor terminal 2 and ECM terminal 67.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
BBIA0354E
BBIA0744E
Voltage: Approximately 5V
PBIA9891J
Continuity should exist.
Revision: December 20092009 QX56

EC-310
< COMPONENT DIAGNOSIS >[VK56DE]
P1550 BATTERY CURRENT SENSOR
5.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E5, F14
 Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK BATTERY CURRENT SENSOR INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between battery curr ent sensor terminal 3 and ECM terminal 71.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E2, F32
 Harness for open or short between battery current sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK BATTERY CURRENT SENSOR
Refer to EC-310, "Component Inspection"
.
OK or NG
OK >> GO TO 9.
NG >> Replace battery negative cable assembly.
9.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003771609
BATTERY CURRENT SENSOR
1. Reconnect harness connectors disconnected.
2. Disconnect battery negative cable (1).
3. Install jumper cable (A) between battery negative terminal and
body ground.
4. Turn ignition switch ON. Continuity should exist.
BBIA0745E
Revision: December 20092009 QX56

P1550 BATTERY CURRENT SENSOREC-311
< COMPONENT DIAGNOSIS > [VK56DE]
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5. Check voltage between ECM terminal 71 (battery current sensor
signal) and ground.
6. If NG, replace battery negative cable assembly. Voltage: Approximately 2.5V
PBIB2617E
Revision: December 20092009 QX56