light INFINITI QX56 2011 Factory Service Manual

ECM
EC-73
< ECU DIAGNOSIS INFORMATION > [VK56VD]
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TP SEN 1-B1
 Ignition switch: ON
(Engine stopped)
 Selector lever: D position Accelerator pedal: Fully released More than 0.36 V
Accelerator pedal: Fully depressed Less than 4.75 V
TP SEN 2-B1*
1 Ignition switch: ON (Engine stopped)
 Selector lever: D position Accelerator pedal: Fully released More than 0.36 V
Accelerator pedal: Fully depressed Less than 4.75 V
FUEL T/TMP SE  Ignition switch: ON Indicates fuel tank tempera-
ture
EVAP SYS PRES  Ignition switch: ON Approx. 1.8 - 4.8 V
FUEL LEVEL SE  Ignition switch: ON Depending on fuel level of
fuel tank
START SIGNAL  Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS  Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG  Engine: After warming up, idle
the engine Air conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)
ON
PW/ST SIGNAL  Engine: After warming up, idle
the engine Steering wheel: Not being turned OFF
Steering wheel: Being turned ON
LOAD SIGNAL  Ignition switch: ON Rear window defogger switch: ON
and/or
Lighting switch: 2nd position
ON
Rear window defogger switch and lighting
switch: OFF OFF
IGNITION SW  Ignition switch: ON → OFF → ON ON → OFF → ON
HEATER FAN SW  Engine: After warming up, idle
the engine Heater fan switch: ON ON
Heater fan switch: OFF OFF
BRAKE SW  Ignition switch: ON Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
IGN TIMING  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 1 - 4
°BTDC
2,000 rpm 25 - 45 °BTDC
COMBUSTION — These items are displayed
but are not applicable to this
model.
CAL/LD VALUE  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 5 - 35%
2,500 rpm 5 - 35%
MASS AIRFLOW  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 2.0 - 6.0 g/s
2,500 rpm 7.0 - 20.0 g/s
PURG VOL C/V  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle
(Accelerator pedal: Not depressed even
slightly, after engine starting.)
0%
2,000 rpm 5%
INT/V SOL (B1)  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 0 - 2%
2,000 rpm Approx. 0 - 50%
Monitor Item Condition Values/Status
Revision: 2010 May2011 QX56

EC-74
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
INT/V SOL (B2) Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 0 - 2%
2,000 rpm Approx. 0 - 50%
AIR COND RLY  Engine: After warming up, idle
the engine A/C switch: OFF OFF
A/C switch: ON
(Compressor operates)
ON
VENT CONT/V  Ignition switch: ON OFF
THRTL RELAY  Ignition switch: ON ON
A/F S1 HTR (B1)  Engine: After warming up, idle the engine
(More than 140 seconds after starting engine) 4 - 100%
A/F S1 HTR (B2)  Engine: After warming up, idle the engine
(More than 140 seconds after starting engine) 4 - 100%
HO2S2 HTR (B1)  Engine speed: Below 3,600 rpm after the following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load ON
 Engine speed: Above 3,600 rpm OFF
HO2S2 HTR (B2)  Engine speed: Below 3,600 rpm after the following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load ON
 Engine speed: Above 3,600 rpm OFF
ALT DUTY SIG  Power generation voltage variable control: Operating ON
 Power generation voltage variable control: Not operating OFF
I/P PULLY SPD  Vehicle speed: More than 20 km/h (12 MPH) Almost the same speed as
the tachometer indication
VEHICLE SPEED  Turn drive wheels and compare CONSULT-III value with the speedometer in-
dication. Almost the same speed as
the speedometer indication
IDL A/V LEARN  Engine: Running Idle air volume learning has not been per-
formed yet.
YET
Idle air volume learning has already been
performed successfully. CMPLT
TRVL AFTER MIL  Ignition switch: ON Vehicle has traveled after MIL has illumi-
nated.0 - 65,535 km
(0 - 40,7
23 miles)
SNOW MODE SW  Ignition switch: ON Snow mode switch: ON ON
Snow mode switch: OFF OFF
ENG OIL TEMP  Engine: After warming up More than 70 °C (158 °F)
MAIN SW  Ignition switch: ON MAIN switch: Pressed ON
MAIN switch: Released OFF
CANCEL SW  Ignition switch: ON CANCEL switch: Pressed ON
CANCEL switch: Released OFF
RESUME/ACC SW  Ignition switch: ON RESUME/ACCELERATE switch:
Pressed
ON
RESUME/ACCELERATE switch: Re-
leased OFF
SET SW  Ignition switch: ON SET/COAST switch: Pressed ON
SET/COAST switch: Released OFF
BRAKE SW1
(ASCD/ICC brake
switch)  Ignition switch: ON
Brake pedal: Fully released ON
Brake pedal: Slightly depressed OFF
Monitor Item Condition Values/Status
Revision: 2010 May2011 QX56

ECM
EC-75
< ECU DIAGNOSIS INFORMATION > [VK56VD]
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BRAKE SW2
(Stop lamp switch)
 Ignition switch: ON Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DIST SW  Ignition switch: ON DISTANCE switch: Pressed ON
DISTANCE switch: Released OFF
CRUISE LAMP  Ignition switch: ON MAIN switch: Pressed at the 1st time
→
at the 2nd time ON
→ OFF
AC EVA TEMP  Engine: Running Indicates A/C evaporator
temperature sent from“uni-
fied meter and A/C amp.”.
AC EVA TARGET  Engine: Running Indicates target A/C evapo-
rator temperature sentfrom
“unified meter and A/C
amp.”.
FAN DUTY  Engine: Running 0 - 100%
ALT DUTY  Engine: Idle 0 - 80%
BAT CUR SEN  Engine speed: Idle
 Battery: Fully charged*
2
 Selector lever: P or N position
 A/C switch: OFF
No load Approx. 2,600 - 3,500 mV
A/F ADJ-B1  Engine: Running −0.330 - 0.330
A/F ADJ-B2  Engine: Running −0.330 - 0.330
P/N POSI SW  Ignition switch: ON Selector lever: P or N ON
Selector lever: Except above position OFF
INT/A TEMP SE  Ignition switch: ON Indicates intake air temper-
ature
AC PRESS SEN  Engine: Idle
 Both A/C switch and blower fan switch: ON (Compressor operates) 1.0 - 4.0 V
FUEL PRES SEN  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle Approx. 2.74 Mpa
2,000 rpm Approx. 3.0 Mpa
FUEL INJ B1  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle Approx. 1.4 msec
2,000 rpm Approx. 1.0 msec
FUEL INJ B2  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle Approx. 1.4 msec
2,000 rpm Approx. 1.0 msec
INT/V TIM (B1)  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle
−5 - 5 °CA
2,000 rpm Approx. 0 - 30 °CA
INT/V TIM (B2)  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle
−5 - 5 °CA
2,000 rpm Approx. 0 - 30 °CA
MAP SENSOR  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle Approx. 1.0 V
2,000 rpm Approx. 1.35 V
EVAP LEAK DIAG  Ignition switch: ON Indicates the condition of
EVAP leak diagnosis.
Monitor Item Condition Values/Status
Revision: 2010 May2011 QX56

ECM
EC-85
< ECU DIAGNOSIS INFORMATION > [VK56VD]
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64
(V/W) 175
(B) EVAP canister purge volume
control solenoid valve
Output[Engine is running]
 Idle speed
 Accelerator pedal: Not depressed
even slightly, after engine starting BATTERY VOLTAGE
(11 - 14 V)
[Engine is running]
 Engine speed: About 2,000 rpm (More than 100 seconds after start-
ing engine) BATTERY VOLTAGE
(11 - 14 V)
67
(V) 175
(B) Manifold absolute pressure sen-
sor
Input[Engine is running]
 Warm-up condition
 Idle speed
1.2 V
[Engine is running]
 Warm-up condition
 Engine speed: 2,000 rpm 1.5 V
68
(BR/
W) —
Sensor ground
[Camshaft position sensor (bank
1)] —— —
70
(W/L) —Sensor ground
(Manifold absolute pressure
sensor)
—— —
73
(P) 99
(LG/ B) Camshaft position sensor (bank
2)
Input[Engine is running]
 Warm-up condition
 Idle speed
NOTE:
The pulse cycle changes depending
on rpm at idle 3.0 - 5.0 V
[Engine is running]
 Engine speed: 2,000 rpm 3.0 - 5.0 V
74
(L) 175
(B) A/F sensor 1 (bank 2) Input [Ignition switch: ON] 2.5 V
76
(W/
G) 98
(G/
W) Sensor power supply
(Crankshaft position sensor)
— [Ignition switch: ON] 5 V
77
(Y/R) 68
(BR/ W) Sensor power supply
[Camshaft position sensor (bank
1)]
— [Ignition switch: ON] 5 V
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
OutputJMBIA0039GB
JMBIA0040GB
JMBIA0045GB
JMBIA0046GB
Revision: 2010 May2011 QX56

EC-92
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
142
(R/W) 175
(B) Fuel pump control module
(FPCM) check
Input[When cranking engine] 0 V
[Engine is running]
 Warm-up condition
 Idle speed
9 V
143
(L/Y) 150
(R) EVAP control system pressure
sensor
Input [Ignition switch: ON] 1.8 - 4.8 V
144
(O/B) 150
(R) Refrigerant pressure sensor Input [Engine is running]
 Warm-up condition
 Both A/C switch and blower fan mo-
tor switch: ON (Compressor oper-
ates) 1.0 - 4.0 V
146 (L) — CAN communication line — — —
147
(G/Y) 175
(B) ASCD/ICC brake switch Input [Ignition switch: ON]
 Brake pedal: Slightly depressed
0 V
[Ignition switch: ON]
 Brake pedal: Fully released BATTERY VOLTAGE
(11 - 14 V)
150 (R) —Sensor ground
(Refrigerant pressure sensor/
Battery current sensor/EVAP
control system pressure sensor) —— —
151 (P) — CAN communication line — — —
156 (L) 175
(B) Power supply
for ECM (Back-
up) Input [Ignition switch: OFF] BATTERY VOLTAGE
(11 - 14 V)
158
(W/B) 175
(B) Stop lamp switch Input [Ignition switch: OFF]
 Brake pedal: Fully released
0 V
[Ignition switch: OFF]
 Brake pedal: Slightly depressed BATTERY VOLTAGE
(11 - 14 V)
161 (R/W) — ENG communication line — — —
163
(L/G) 175
(B) ECM relay (Self shut-off) Output [Engine is running]
[Ignition switch: OFF]
 A few seconds after turning ignition
switch OFF 0 - 1.5 V
[Ignition switch: OFF]
 More than a few seconds after turn- ing ignition switch OFF BATTERY VOLTAGE
(11 - 14 V)
165
(GR/ R) —
NOTE:
Not used —— —
166 (W) — ENG communication line — — —
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
Revision: 2010 May2011 QX56

EC-140
< BASIC INSPECTION >[VK56VD]
BASIC INSPECTION
2. Rev engine between 2,000 and 3,000 rpm 2 or 3 times under no
load, then run engine at idle speed for approximately 1 minute.
3. Check idle speed.
For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 4.
4.PERFORM ACCELERATOR PEDAL RE LEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-146, "
Work Procedure".
>> GO TO 5.
5.PERFORM THROTTLE VALVE CL OSED POSITION LEARNING
Perform EC-147, "
Work Procedure".
>> GO TO 6.
6.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-148, "
Work Procedure".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 7.
NO >> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.
7.CHECK IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the Following.
 Check camshaft position sensor and circuit. Refer to EC-303, "
DTC Logic".
 Check crankshaft position sensor and circuit. Refer to EC-299, "
DTC Logic".
Is the inspection result normal?
YES >> GO TO 9.
NO >> Repair or replace malfunctioning part. Then GO TO 4.
9.CHECK ECM FUNCTION
1. Substitute with a non-malfunctioning ECM to check EC M function. (ECM may be the cause of the incident,
although this is rare.)
2. Perform initialization of IVIS (NATS) system and regist ration of all IVIS (NATS) ignition key IDs. Refer to
SEC-51, "
ECM : Work Procedure".
>> GO TO 4.
10.CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light. For procedure, refer to EC-531, "
Inspection".
PBIA8513J
Revision: 2010 May2011 QX56

BASIC INSPECTIONEC-141
< BASIC INSPECTION > [VK56VD]
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For specification, refer to
EC-538, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 19.
NO >> GO TO 11.
11 .PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-146, "
Work Procedure".
>> GO TO 12.
12.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-147, "
Work Procedure".
>> GO TO 13.
13.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-148, "
Work Procedure".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 14.
NO >> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.
14.CHECK IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 15.
NO >> GO TO 17.
15.CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light. For procedure, refer to EC-531, "
Inspection".
For specification, refer to EC-538, "
Ignition Timing".
Is the inspection result normal?
YES >> GO TO 19.
NO >> GO TO 16.
16.CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-62, "
Removal and Installation".
Is the inspection result normal?
YES >> GO TO 17.
NO >> Repair the timing chain installation. Then GO TO 4.
17.DETECT MALFUNCTIONING PART
Check the following.
 Check camshaft position sensor and circuit. Refer to EC-303, "
DTC Logic".
 Check crankshaft position sensor and circuit. Refer to EC-299, "
DTC Logic".
Is the inspection result normal?
YES >> GO TO 18.
NO >> Repair or replace malfunctioning part. Then GO TO 4.
18.CHECK ECM FUNCTION
1. Substitute with a non-malfunctioning ECM to check EC M function. (ECM may be the cause of the incident,
although this is rare.)
Revision: 2010 May2011 QX56

EC-148
< BASIC INSPECTION >[VK56VD]
IDLE AIR VOLUME LEARNING
IDLE AIR VOLUME LEARNING
DescriptionINFOID:0000000006217750
Idle Air Volume Learning is a function of ECM to learn
the idle air volume that keeps engine idle speed within
the specific range. It must be perfo rmed under the following conditions:
 Each time the electric throttle control actuator or ECM is replaced.
 Idle speed or ignition timing is out of the specification.
Work ProcedureINFOID:0000000006217751
1.PRECONDITIONING
Check that all of the following conditions are satisfied.
Learning will be cancelled if any of the follo wing conditions are missed for even a moment.
 Battery voltage: More than 12.9 V (At idle)
 Engine coolant temperature: 70 - 105 °C (158 - 221 °F)
 Selector lever position: P or N
 Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
started the headlamp will not illuminate.
 Steering wheel: Neutral (Straight-ahead position)
 Vehicle speed: Stopped
 Transmission: Warmed-up
- With CONSULT-III: Drive vehicle until “ATF TEMP 2” in “DATA MONITOR” mode of “A/T” system indicates
less than 0.9 V.
- Without CONSULT-III: Drive vehicle for 10 minutes.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 3.
2.PERFORM IDLE AIR VOLUME LEARNING
WITH CONSULT-III
1. Perform Accelerator Pedal Released Position Learning. Refer to EC-146, "
Work Procedure".
2. Perform Throttle Valve Closed Position Learning. EC-147, "
Work Procedure".
3. Start engine and warm it up to normal operating temperature.
4. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
5. Touch “START” and wait 20 seconds.
Is
“CMPLT” displayed on CONSULT-III screen?
YES >> GO TO 4.
NO >> GO TO 5.
3.PERFORM IDLE AIR VOLUME LEARNING
WITHOUT CONSULT-III
NOTE:
 It is better to count the ti me accurately with a clock.
 It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
1. Perform Accelerator Pedal Released Position Learning. Refer to EC-146, "
Work Procedure".
2. Perform Throttle Valve Closed Position Learning. EC-147, "
Work Procedure".
3. Start engine and warm it up to normal operating temperature.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Confirm that accelerator pedal is fully releas ed, turn ignition switch ON and wait 3 seconds.
6. Repeat the following procedure quickly 5 times within 5 seconds.
- Fully depress the accelerator pedal.
- Fully release the accelerator pedal.
7. Wait 7 seconds, fully depress the accelerator pedal for approx. 20 seconds until the MIL stops blinking
and turns ON.
8. Fully release the accelerator pedal within 3 seconds after the MIL turns ON.
Revision: 2010 May2011 QX56

FUEL PRESSUREEC-153
< BASIC INSPECTION > [VK56VD]
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FUEL PRESSURE
Work ProcedureINFOID:0000000006217756
FUEL PRESSURE RELEASE
WITH CONSULT-III
1. Turn ignition switch ON.
2. Perform “FUEL PRESSURE RELEASE” in
“WORK SUPPORT” mode with CONSULT-III.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
WITHOUT CONSULT-III
1. Remove fuel pump fuse in IPDM E/R. NOTE:
 For the fuse number, refer to EC-114, "
Wiring Diagram".
 For the fuse arrangement, refer to PG-143, "
Fuse, Connector and Terminal Arrangement".
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel pressure.
4. Turn ignition switch OFF.
5. Reinstall fuel pump fuse after servicing fuel system.
LOW FUEL PRESSURE CHECK
CAUTION:
 Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.
 The fuel hose connection method used when taking fuel pressure check must not be used for other
purposes.
 Do not perform fuel pressure check with electrical syst ems operating (i.e. lights, rear defogger, A/C,
etc.) Fuel pressure gauge may indicate false readin gs due to varying engine load and changes in
manifold vacuum.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out.
1. Release fuel pressure to zero.
2. Prepare fuel hose for fuel pressure check (B) and fuel tube adapter [SST (KV10118400)] (D), then connect fuel pressure
gauge (A).
CAUTION:
 Use suitable fuel hose for fuel pressure check (genuine
NISSAN fuel hose without quick connector).
 To avoid unnecessary force or tension to hose, use mod-
erately long fuel hose for fuel pressure check.
 Do not use the fuel hose for checking fuel pressure with damage or cracks on it.
 Use Pressure Gauge to check fuel pressure.
3. Disconnect fuel feed hose from fuel tube. Refer to EM-43, "
Exploded View".
CAUTION:
Do not twist or kink fuel hose because it is plastic hose.
To quick connector
To fuel tube (engine side)
C : Hose clamp
PBIB2982E
Revision: 2010 May2011 QX56

P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
EC-291
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0300, P0301, P0302, P0303, P0304,
P0305, P0306, P0307, P0308 MIS-
FIRE
DTC LogicINFOID:0000000006217840
DTC DETECTION LOGIC
When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the crank-
shaft position (CKP) sensor signal to vary, ECM can determine that a misfire is occurring.
The misfire detection logic consists of the following two conditions.
1. One Trip Detection Logic (Three Way Catalyst Damage) On the 1st trip that a misfire condition occurs that can damage the three way catalyst (TWC) due to over-
heating, the MIL will blink.
When a misfire condition occurs, the ECM monitors the CKP sensor signal every 200 engine revolutions
for a change.
When the misfire condition decreases to a level t hat will not damage the TWC, the MIL will turn off.
If another misfire condition occurs that can damage the TWC on a second trip, the MIL will blink.
When the misfire condition decreases to a level t hat will not damage the TWC, the MIL will remain on.
If another misfire condition occurs that can damage the TWC, the MIL will begin to blink again.
2. Two Trip Detection Logic (Exhaust quality deterioration) For misfire conditions that will not damage the TWC (but will affect vehicle emissions), the MIL will only
light when the misfire is detected on a second trip. Du ring this condition, the ECM monitors the CKP sen-
sor signal every 1,000 engine revolutions.
A misfire malfunction can be detected in any one cylinder or in multiple cylinders.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
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.
Sensor Input signal to ECM ECM function
Crankshaft position sensor Engine speed On board diagnosis of misfire
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0300 MULTI CYL MISFIRE
(Multiple cylinder misfires detected) Multiple cylinders misfire.
 Improper spark plug
 Insufficient compression
 Incorrect fuel pressure
 The fuel injector circuit is open or shorted
 Fuel injector
 Intake air leakage
 The ignition signal circuit is open or shorted
 Lack of fuel
 Signal plate
 A/F sensor 1
 Incorrect PCV hose connection
P0301
CYL 1 MISFIRE
(No.1 cylinder misfire detected)
No. 1 cylinder misfires.
P0302 CYL 2 MISFIRE
(No. 2 cylinder misfire detected) No. 2 cylinder misfires.
P0303 CYL 3 MISFIRE
(No. 3 cylinder misfire detected) No. 3 cylinder misfires.
P0304 CYL 4 MISFIRE
(No. 4 cylinder misfire detected)
No. 4 cylinder misfires.
P0305 CYL 5 MISFIRE
(No. 5 cylinder misfire detected) No. 5 cylinder misfires.
P0306 CYL 6 MISFIRE
(No. 6 cylinder misfire detected) No. 6 cylinder misfires.
P0307 CYL 7 MISFIRE
(No. 7 cylinder misfire detected)
No. 7 cylinder misfires.
P0308 CYL 8 MISFIRE
(No. 8 cylinder misfire detected) No. 8 cylinder misfires.
Revision: 2010 May2011 QX56