sensor INFINITI QX56 2010 Factory Service Manual

P0643 SENSOR POWER SUPPLYEC-289
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P0643 SENSOR POWER SUPPLY
On Board Diagnosis LogicINFOID:0000000005149328
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:0000000005149329
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. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-289, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149330
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-85, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
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
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EC-290
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P0643 SENSOR POWER SUPPLY
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-248, "
Component Inspection".)
• Power steering pressure sensor (Refer to EC-283, "
Component Inspection".)
• Battery current sensor (Refer to EC-314, "
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-381, "
Component Inspection".
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
BBIA0361E
Voltage: Approximately 5 V
JMBIA0601ZZ
ECM terminal Sensor terminal Reference Wiring Diagram
48 EVAP control system pressure sensor terminal 3
EC-435, "
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
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P0643 SENSOR POWER SUPPLYEC-291
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6.REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal position assembly.
2. Perform EC-18, "
Accelerator Pedal Released Position Learning".
3. Perform EC-18, "
Throttle Valve Closed Position Learning".
4. Perform EC-18, "
Idle Air Volume Learning".
>> INSPECTION END
7.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
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P1140, P1145 IVT CONTROL POSITION SENSOR
EC-295
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P1140, P1145 IVT CONTROL POSITION SENSOR
Component DescriptionINFOID:0000000005149336
Intake valve timing control position sensors are located in the front of
cylinder heads in both bank 1 and bank 2.
This sensor uses a Hall IC.
The cam position is determined by the intake camshaft sprocket con-
cave (in four places). The ECM provides feedback to the intake valve
timing control for appropriate target valve open-close timing accord-
ing to drive conditions based on detected cam position.
On Board Diagnosis LogicINFOID:0000000005149337
DTC Confirmation ProcedureINFOID:0000000005149338
1. If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Turn ignition switch ON.
c. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Maintain the following conditions for at least 10 seconds.
4. Check 1st trip DTC.
5. If 1st trip DTC is detected, go to EC-295, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149339
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
SEF359Z
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P1140
11 4 0
(Bank 1)
Intake valve timing control
position sensor circuit An excessively high or low voltage from the
sensor is sent to ECM. • Harness or connectors
(Intake valve timing control position
sensor circuit is open or shorted)
• Intake valve timing control position sensor
• Crankshaft position sensor (POS)
• Camshaft positi on sensor (PHASE)
• Accumulation of debris to the signal pick-up portion of the camshaft sprock-
et
P1145
11 4 5
(Bank 2)
ENG SPEED
More than idle speed
Selector lever P or N position
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EC-296
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P1140, P1145 IVT CONTROL POSITION SENSOR
Refer to EC-85, "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
PBIB2613E
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P1140, P1145 IVT CONTROL POSITION SENSOR
EC-297
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3. Also check harness for short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E2, F32
• Harness for open or short between intake valve timing control position sensor and ground
>> Repair open circuit or short to power in harness or connectors.
6.CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN
AND SHORT1. Disconnect ECM harness connector.
2. Check harness continuity between the following; ECM terminal 72 and intake valve timing control position sensor (Bank 1) terminal 2 or
ECM terminal 53 and intake valve timing contro l position sensor (Bank 2) terminal 2.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR
Refer to EC-298, "
Component Inspection".
OK or NG
OK >> GO TO 8.
NG >> Replace malfunctioning intake valve timing control position sensor. Refer to EC-495
.
8.CHECK CRANKSHAFT POSITION SENSOR (POS)
Refer to EC-203, "
Component Inspection".
OK or NG
OK >> GO TO 9.
NG >> Replace crankshaft position sensor (POS).
9.CHECK CAMSHAFT POSITI ON SENSOR (PHASE)
Refer to EC-207, "
Component Inspection".
OK or NG
OK >> GO TO 10.
NG >> Replace camshaft position sensor (PHASE). Refer to EC-495
.
10.CHECK CAMSHAFT SPROCKET
Check accumulation of debris to the signal pick- up portion of the camshaft sprocket. Refer to EM-62, "
Inspec-
tion after Installation".
OK or NG
OK >> GO TO 11.
NG >> Remove debris and clean the signal pick-up cutout of camshaft sprocket.
11 .CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
Continuity should exist.
Continuity should exist.
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EC-298
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P1140, P1145 IVT CONTROL POSITION SENSOR
>>
INSPECTION END
Component InspectionINFOID:0000000005149340
INTAKE VALVE TIMING CONTROL POSITION SENSOR
1. Disconnect intake valve timing control position sensor harness connector.
2. Loosen the fixing bolt of the sensor.
3. Remove the sensor.
4. Visually check the sensor for chipping.
5. Check resistance as shown below.
6. If NG, replace intake valve timing control position sensor. Refer
to EC-495
.
SEF362Z
Terminal No. (Polarity) Resistance Ω [at 25 °C (77 °F)]
3 (+) - 1 (-) Except 0 or ∞
2 (+) - 1 (-)
3 (+) - 2 (-)
JMBIA0600ZZ
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P1148, P1168 CLOSED LOOP CONTROLEC-299
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P1148, P1168 CLOSED LOOP CONTROL
On Board Diagnosis LogicINFOID:0000000005149341
These self-diagnoses have the on
e trip detection logic.
DTC P1148 or P1168 is displayed with another DTC for air fuel ratio (A/F) sensor 1.
Perform the trouble diagnosis for the corresponding DTC.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1148
11 4 8
(Bank 1) Closed loop control
function The closed loop control function for bank 1 does
not operate even when vehicle is driving in the
specified condition.
• Harness or connectors
[The air fuel ratio (A/F) sensor 1 circuit is
open or shorted.]
• Air fuel ratio (A/F) sensor 1
• Air fuel ratio (A/F) sensor 1 heater
P1168
11 6 8
(Bank 2) The closed loop control function for bank 2 does
not operate even when vehicle is driving in the
specified condition.
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P1217 ENGINE OVER TEMPERATUREEC-303
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4. Perform “COOLING FAN” in “ACTIVE TEST” mode with CONSULT-III.
5. If the results are NG, go to
EC-392, "
Diagnosis Procedure".
WITH GST
1. Check the coolant level in the reservoir tank and radiator.
Allow engine to cool befo re checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to EC-392,
"Diagnosis Procedure".
2. Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to EC-392,
"Diagnosis Procedure".
3. Disconnect engine coolant temper ature sensor harness connec-
tor.
4. Connect 150 Ω resistor to engine coolant temperature sensor
harness connector.
5. Start engine and make sure that cooling fan operates. CAUTION:
Be careful not to overheat engine.
6. If NG, go to EC-392, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005149352
1.CHECK COOLING FAN (CRANKSHAFT DRIVEN) OPERATION
1. Start engine and let it idle.
2. Make sure that cooling fan (crankshaft driven) operates normally.
OK or NG
OK (With CONSULT-III)>>GO TO 2.
OK (Without CONSULT-III)>>GO TO 3.
NG >> Check cooling fan (crankshaft driven). Refer to CO-18, "
Removal and Installation (Crankshaft
Driven Type)".
2.CHECK COOLING FAN MOTOR OPERATION
With CONSULT-III
1. Start engine and let it idle.
2. Select “COOLING FAN” in “ACTIVE TEST” mode with CONSULT-III.
3. Make sure that cooling fan operates.
OK or NG
OK >> GO TO 4.
NG >> Check cooling fan control circuit. (Go to “PROCEDURE A”.)
3.CHECK COOLING FAN MOTOR OPERATION
Without CONSULT-III
1. Disconnect engine coolant temperature sensor harness connector.
2. Connect 150 Ω resistor to engine coolant temperature sensor harness connector.
3. Start engine and let it idle.
SEF621W
SEF882V
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EC-304
< COMPONENT DIAGNOSIS >[VK56DE]
P1217 ENGINE OVER TEMPERATURE
4. Make sure that cooling fan operates.
OK or NG
OK >> GO TO 4.
NG >> Check cooling fan control circuit. (Go to “PROCEDURE
A”.)
4.CHECK COOLING SYSTEM FOR LEAK
Refer to CO-10, "
Inspection".
OK or NG
OK >> GO TO 5.
NG >> Check the following for leak. •Hose
• Radiator
• Radiator cap
• Water pump
• Reservoir tank
5.CHECK COMPONENT PARTS
Check the following.
• RESERVOIR TANK CAP (Refer to CO-10, "
Inspection".)
• Thermostat. (Refer to CO-22, "
Removal and Installation".)
• Engine coolant temperature sensor. (Refer to EC-123, "
Component Inspection".)
OK or NG
OK >> GO TO 6.
NG >> Replace malfunctioning component.
6.CHECK MAIN 13 CAUSES
If the cause cannot be isolated, go to EC-304, "
Main 13 Causes of Overheating".
>> INSPECTION END
Main 13 Causes of OverheatingINFOID:0000000005149353
SEF882V
Engine Step Inspection item EquipmentStandardReference page
OFF 1 • Blocked radiator • Blocked condenser
• Blocked radiator grille
• Blocked bumper • Visual
No blocking —
2 • Coolant mixture • Coolant tester 50 - 50% coolant mixtureCO-10
3 • Coolant level • VisualCoolant up to MAX level in
reservoir tank and radiator
filler neck CO-11, "Changing Engine
Coolant"
4 • Reservoir tank cap • Pre
ssure tester 95 - 125 kPa
(0.97 - 1.28 kg/cm2, 14 -
18 psi) (Limit) CO-10, "
Inspection"
ON*25 • Coolant leaks
• VisualNo leaks CO-10, "Inspection"
ON*26 • Thermostat • Touch the upper and
lower radiator hoses Both hoses should be hot
CO-22, "Removal and In-
stallation"
ON*17 • Cooling fan • CONSULT-IIIOperating See trouble diagnosis for
DTC P1217 ( EC-36
).
Revision: April 20092010 QX56