fuel injector INFINITI QX56 2011 Factory Owner's Manual

EC-100
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
P0139 0139 HO2S2 (B1)
×2×EC-257
P0150 0150 A/F SENSOR1 (B2) ×2×EC-228
P0151 0151 A/F SENSOR1 (B2) — 2 ×EC-232
P0152 0152 A/F SENSOR1 (B2) — 2 ×EC-235
P0153 0153 A/F SENSOR1 (B2) ×2×EC-238
P0157 0157 HO2S2 (B2) ×2×EC-243
P0158 0158 HO2S2 (B2) ×2×EC-249
P0159 0159 HO2S2 (B2) ×2×EC-257
P0171 0171 FUEL SYS-LEAN-B1 — 2 ×EC-263
P0172 0172 FUEL SYS-RICH-B1 — 2 ×EC-267
P0174 0174 FUEL SYS-LEAN-B2 — 2 ×EC-263
P0175 0175 FUEL SYS-RICH-B2 — 2 ×EC-267
P0181 0181 FTT SENSOR — 2 ×EC-271
P0182 0182 FTT SEN/CIRCUIT — 2 ×EC-274
P0183 0183 FTT SEN/CIRCUIT — 2 ×EC-274
P0190 0190 FUEL PRES SEN/CIRC — 1 ×EC-276
P0191 0191 FRP SENSOR A — 2 ×EC-279
P0192 0192 FRP SEN/CIRC — 2 ×EC-276
P0193 0193 FRP SEN/CIRC — 2 ×EC-276
P0196 0196 EOT SENSOR — 2 ×EC-283
P0197 0197 EOT SEN/CIRC — 2 ×
EC-285
P0198 0198 EOT SEN/CIRC — 2 ×
P0201 0201 INJECTOR CIRC-CYL1 — 2 ×
EC-287
P0202 0202 INJECTOR CIRC-CYL2 — 2 ×
P0203 0203 INJECTOR CIRC-CYL3 — 2 ×
P0204 0204 INJECTOR CIRC-CYL4 — 2 ×
P0205 0205 INJECTOR CIRC-CYL5 — 2 ×
P0206 0206 INJECTOR CIRC-CYL6 — 2 ×
P0207 0207 INJECTOR CIRC-CYL7 — 2 —
P0208 0208 INJECTOR CIRC-CYL8 — 2 —
P0222 0222 TP SEN 1/CIRC-B1 — 1 ×
EC-288
P0223 0223 TP SEN 1/CIRC-B1 — 1 ×
P0300 0300 MULTI CYL MISFIRE — 1 or 2 ×
EC-291
P0301 0301 CYL 1 MISFIRE — 1 or 2 ×
P0302 0302 CYL 2 MISFIRE — 1 or 2 ×
P0303 0303 CYL 3 MISFIRE — 1 or 2 ×
P0304 0304 CYL 4 MISFIRE — 1 or 2 ×
P0305 0305 CYL 5 MISFIRE — 1 or 2 ×
P0306 0306 CYL 6 MISFIRE — 1 or 2 ×
P0307 0307 CYL 7 MISFIRE — 1 or 2 ×
P0308 0308 CYL 8 MISFIRE — 1 or 2 ×
DTC*
1
Items
(CONSULT-III screen terms) SRT code Trip MIL Reference
page
CONSULT-III
GST*
2ECM*3
Revision: 2010 May2011 QX56

EC-164
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
NOTE:
Check “A/F ALPHA-B1” and “A/F ALPHA-B2” for approxim
ately 1 minute because they may fluctuate. It is
NG if the indication is out of the SP value even a little.
Is the measurement value within the SP value?
YES >> GO TO 14.
NO-1 >> Less than the SP value: GO TO 2.
NO-2 >> More than the SP value: GO TO 3.
2.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and check that the indication is within the SP
value.
Is the measurement value within the SP value?
YES >> GO TO 4.
NO >> More than the SP value: GO TO 16.
3.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and check that the indication is within the SP
value.
Is the measurement value within the SP value?
YES >> GO TO 6.
NO-1 >> More than the SP value: GO TO 6.
NO-2 >> Less than the SP value: GO TO 22.
4.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Stop the engine.
2. Disconnect PCV hose, and then plug it.
3. Start engine.
4. Select “A/F ALPHA-B1” and “A/F ALPHA-B2” in “ SPEC” of “DATA MONITOR” mode, and check that each
indication is within the SP value.
Is the measurement value within the SP value?
YES >> GO TO 5.
NO >> GO TO 6.
5.CHANGE ENGINE OIL
1. Stop the engine.
2. Change engine oil. NOTE:
This symptom may occur when a large amount of gasoline is mixed with engine oil because of driving
conditions (such as when engine oil temperature does not rise enough since a journey distance is too
short during winter). The symptom will not be detec ted after changing engine oil or changing driving con-
ditions.
>> INSPECTION END
6.PERFORM POWER BALANCE TEST
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode.
2. Check that each cylinder produces a momentary engine speed drop.
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following below.
 Ignition coil and its circuit (Refer to EC-506, "
Component Function Check".)
 Fuel injector and its circuit (Refer to EC-498, "
Component Function Check".)
 Intake air leakage
 Low compression pressure (Refer to EM-16, "
Inspection".)
Is the inspection result normal?
Revision: 2010 May2011 QX56

TROUBLE DIAGNOSIS - SPECIFICATION VALUEEC-165
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YES >> Replace fuel injector and then GO TO 8.
NO >> Repair or replace malfunctioning part and then GO TO 8.
8.CHECK “A/F ALPHA-B1” AND “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1” and “A/F ALPHA-B2” in “S PEC” of “DATA MONITOR” mode, and check that each
indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO >> GO TO 9.
9.CHECK A/F SENSOR 1 FUNCTION
Perform all DTC CONFIRMATION PROCEDURE related with A/F sensor 1.
 For DTC P0130, P0150, refer to EC-228, "
DTC Logic".
 For DTC P0131, P0151, refer to EC-232, "
DTC Logic".
 For DTC P0132, P0152, refer to EC-235, "
DTC Logic".
 For DTC P0133, P0153, refer to EC-238, "
DTC Logic".
 For DTC P2A00, P2A03, refer to EC-487, "
DTC Logic".
Are any DTCs detected?
YES >> GO TO 10.
NO >> GO TO 12.
10.CHECK A/F SENSOR 1 CIRCUIT
Perform Diagnosis Procedure according to corresponding DTC.
>> GO TO 11.
11 .CHECK “A/F ALPHA-B1” AND “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1” and “A/F ALPHA-B2” in “S PEC” of “DATA MONITOR” mode, and check that each
indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO >> GO TO 12.
12.DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect ECM harness connector. Check pin term inal and connector for damage, and then reconnect it.
>> GO TO 13.
13.CHECK “A/F ALPHA-B1” AND “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1” and “A/F ALPHA-B2” in “S PEC” of “DATA MONITOR” mode, and check that each
indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO >> Detect malfunctioning part according to EC-524, "
Symptom Table".
14.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and check t hat the indication is within the SP
value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO-1 >> More than the SP value: GO TO 15.
NO-2 >> Less than the SP value: GO TO 22.
15.DETECT MALFUNCTIONING PART
Revision: 2010 May2011 QX56

EC-238
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0133, P0153 A/F SENSOR 1
P0133, P0153 A/F SENSOR 1
DTC LogicINFOID:0000000006217811
DTC DETECTION LOGIC
To judge the malfunction of A/F sensor
1, this diagnosis measures response time of the A/F signal computed
by ECM from the A/F sensor 1 signal. The time is compensated by engine operating (speed and load), fuel
feedback control constant, and the A/F sensor 1 temper ature index. Judgment is based on whether the com-
pensated time (the A/F signal cycling time index) is inordinately long or not.
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.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 5.
2.PERFORM DTC CONFIRMATION PROCEDURE-I
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
6. Let engine idle for 1 minute.
7. Select “A/F SEN1(B1) P1278/P1279” (for DTC P 0133) or “A/F SEN1(B2) P1288/P1289” (for DTC P0153)
of “A/F SEN1” in “DTC WORK SUPPORT” mode with CONSULT-III.
8. Touch “START”.
Is
“COMPLETED” displayed on CONSULT-III screen?
YES >> GO TO 3
NO >> GO TO 4.
3.PERFORM DTC CONFIRMATION PROCEDURE-II
Touch “SELF-DIAG RESULT”.
Which is displayed on CONSULT-III screen?
OK >> INSPECTION END
NG >> Go to EC-239, "
Diagnosis Procedure".
4.PERFORM DTC CONFIRMATION PROCEDURE-II
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible Cause
P0133 A/F SENSOR1 (B1)
[Air fuel ratio (A/F) sensor 1
(bank 1) circuit slow response]
 The response of the A/F signal computed by ECM from A/F sensor 1 signal takes
more than the specified time.  Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
 A/F sensor 1
 A/F sensor 1 heater
 Fuel pressure
 Fuel injector
 Intake air leaks
 Exhaust gas leaks
PCV
 Mass air flow sensor
P0153
A/F SENSOR1 (B2)
[Air fuel ratio (A/F) sensor 1
(bank 2) circuit slow response]
Revision: 2010 May2011 QX56

P0133, P0153 A/F SENSOR 1EC-239
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1. After perform the following procedure, “TESTIN
G” will be displayed on the CONSULT-III screen.
- Increase the engine speed up to between 4,000 and 5,000 rpm and maintain that speed for 10 seconds.
- Fully release accelerator pedal and then let engine idle for approximately 10 seconds. If “TESTING” is not displayed after 10 seconds, refer to EC-161, "
Component Function Check".
2. Wait for approximately 20 seconds at idle under t he condition that “TESTING” is displayed on the CON-
SULT-III screen.
3. Check that “TESTING” changes to “COMPLETED”. If “TESTING” changed to “OUT OF CONDITION”, refer to EC-161, "
Component Function Check".
4. Touch “SELF-DIAG RESULT”.
Which is displayed on CONSULT-III screen?
OK >> INSPECTION END
NG >> Go to EC-239, "
Diagnosis Procedure".
5.CHECK AIR-FUEL RATIO SELF-LEARNING VALUE
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Select Service $01 with GST.
3. Calculate the total value of “Short term f uel trim” and “Long term fuel trim” indications.
Is the total percentage within
±15%?
YES >> GO TO 7.
NO >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Intake air leaks
 Exhaust gas leaks
 Incorrect fuel pressure
 Lack of fuel
 Fuel injector
 Incorrect PCV hose connection
PCV valve
 Mass air flow sensor
>> Repair or replace malfunctioning part.
7.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
3. Let engine idle for 1 minute.
4. Increase the engine speed up to between 4,000 and 5,000 rpm and maintain that speed for 10 seconds.
5. Fully release accelerator pedal and then let engine idle for approximately 1 minute.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-239, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217812
1.RETIGHTEN AIR FUEL RATIO SENSOR 1
Loosen and retighten the air fuel rati o (A/F) sensor 1. Refer to EM-40, "
Exploded View".
>> GO TO 2.
2.CHECK EXHAUST GAS LEAKAGE
1. Start engine and run it at idle.
Revision: 2010 May2011 QX56

P0137, P0157 HO2S2EC-243
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P0137, P0157 HO2S2
DTC LogicINFOID:0000000006217813
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel
ratio (A/F) sensor 1. The oxy-
gen storage capacity of the three way catalyst (manifold) causes the
longer switching time. To judge the malfunctions of heated oxygen
sensor 2, ECM monitors whether the maximum voltage of the sensor
is sufficiently high during various driving conditions such as fuel cut.
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.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 4.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
6. Let engine idle for 1 minute.
7. Select “DATA MONITOR” mode with CONSULT-III.
8. Check that “COOLAN TEMP/S” indicates more than 70 °C (158 °F).
If not, warm up engine and go to next step w hen “COOLAN TEMP/S” indication reaches 70 °C (158 °F).
9. Open engine hood.
10. Select “HO2S2 (B1) P1147” (for DTC P0137) or “HO2S2 (B2) P1167” (for DTC P0157) of “HO2S2” in
“DTC WORK SUPPORT” mode with CONSULT-III.
11. Follow the instruction of CONSULT-III display.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
12. Touch “SELF-DIAG RESULTS”.
JMBIA1572GB
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0137 HO2S2 (B1)
[Heated oxygen sensor 2
(bank 1) circuit low voltage]
The maximum voltage from the sensor does
not reach the specified voltage.  Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
 Heated oxygen sensor 2
 Fuel pressure
 Fuel injector
 Intake air leaks
P0157
HO2S2 (B2)
[Heated oxygen sensor 2
(bank 2) circuit low voltage]
Revision: 2010 May2011 QX56

P0138, P0158 HO2S2EC-249
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P0138, P0158 HO2S2
DTC LogicINFOID:0000000006217817
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a much longer switching
time between rich and lean than the air fuel ratio (A/
F) sensor 1. The oxygen storage capacity of the thr ee way catalyst (manifold) causes the longer switching
time.
MALFUNCTION A
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the voltage is unusually high during various driving condi-
tions such as fuel cut.
MALFUNCTION B
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the minimum voltage of sensor is sufficiently low during var-
ious driving conditions such as fuel cut.
DTC CONFIRMATION PROCEDURE
PBIB1848E
PBIB2376E
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0138 HO2S2 (B1)
[Heated oxygen sensor 2
(bank 1) circuit high voltage] A)
An excessively high voltage from the
sensor is sent to ECM.  Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
 Heated oxygen sensor 2
B) The minimum voltage from the sensor is
not reached to the specified voltage.  Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
 Heated oxygen sensor 2
 Fuel pressure
 Fuel injector
P0158 HO2S2 (B2)
[Heated oxygen sensor 2
(bank 2) circuit high voltage] A)
An excessively high voltage from the
sensor is sent to ECM.  Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
 Heated oxygen sensor 2
B) The minimum voltage from the sensor is
not reached to the specified voltage.  Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
 Heated oxygen sensor 2
 Fuel pressure
 Fuel injector
Revision: 2010 May2011 QX56

P0139, P0159 HO2S2EC-257
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P0139, P0159 HO2S2
DTC LogicINFOID:0000000006217821
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel
ratio (A/F) sensor 1. The oxy-
gen storage capacity of the three way catalyst (manifold) causes the
longer switching time. To judge the malfunctions of heated oxygen
sensor 2, ECM monitors whether the switching response of the sen-
sor's voltage is faster than specified during various driving conditions
such as fuel cut.
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.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 4.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Restart engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
6. Let engine idle for 1 minute.
7. Select “DATA MONITOR” mode with CONSULT-III.
8. Check that “COOLAN TEMP/S” indicates more than 70 °C (158 °F).
If not, warm up engine and go to next step when “COOLAN TEMP/S” indication reaches to 70°C (158 °F).
9. Open engine hood.
10. Select “HO2S2 (B1) P0139” or “HO2S2 (B2) P 0159” of “HO2S2” in “DTC WORK SUPPORT” mode with
CONSULT-III.
11. Start engine and follow the instruction of CONSULT-III display.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
12. Touch “SELF-DIAG RESULTS”.
SEF302U
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0139 HO2S2 (B1)
[Heated oxygen sensor 2
(bank 1) circuit slow response] It takes more time for the sensor to respond
between rich and lean than the specified
time.  Harness or connectors
(The heated oxygen sensor 2 circuit is
open or shorted)
 Heated oxygen sensor 2
 Fuel pressure
 Fuel injector
 Intake air leaks
P0159
HO2S2 (B2)
[Heated oxygen sensor 2
(bank 2) circuit slow response]
Revision: 2010 May2011 QX56

P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-263
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P0171, P0174 FUEL INJE
CTION SYSTEM FUNCTION
DTC LogicINFOID:0000000006217825
DTC DETECTION LOGIC
With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio f eedback signal from A/F sensor 1. The ECM calculates
the necessary compensation to co rrect the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extrem ely large (the actual mixture ratio is too lean), the
ECM judges the condition as the fuel injection system malfunction and illuminates the MIL (2 trip detection
logic).
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE-I
1. Clear the mixture ratio self-learning value. Refer to EC-152, "
Work Procedure".
2. Start engine.
Is it difficult to start engine?
YES >> GO TO 3.
NO >> GO TO 4.
3.RESTART ENGINE
If it is difficult to start engine, the f uel injection system has a malfunction, too.
Crank engine while depressing accelerator pedal.
NOTE:
When depressing accelerator pedal three fourths (3/4) or more, the control system does not start the engine.
Do not depress accelerator pedal too much.
Does engine start?
YES >> Proceed to EC-264, "Diagnosis Procedure".
NO >> Check exhaust and intake air leakage visually.
4.PERFORM DTC CONFIRMATION PROCEDURE-II
1. Keep engine idle for at least 5 minutes.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-264, "Diagnosis Procedure".
Sensor Input signal to ECM ECM function Actuator
A/F sensor 1 Density of oxygen in exhaust gas
(Mixture ratio feedback signal) Fuel injection control Fuel injector
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0171 FUEL SYS-LEAN-B1
[Fuel injection system too
lean (bank 1)]
 Fuel injection system does not operate properly.
 The amount of mixture ratio compensation is too
large. (The mixture ratio is too lean.)  Intake air leakage
 A/F sensor 1
 Fuel injector
 Exhaust gas leakage
 Incorrect fuel pressure
 Lack of fuel
 Mass air flow sensor
 Incorrect PCV hose connection
P0174
FUEL SYS-LEAN-B2
[Fuel injection system too
lean (bank 2)]
Revision: 2010 May2011 QX56

P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-265
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5. Check the continuity between
A/F sensor 1 harness connector and ground, or ECM harness connector
and ground.
6. Also check harness for short to power.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK FUEL PRESSURE
Check fuel pressure. Refer to EC-153, "
Work Procedure".
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check fuel hoses and fuel tubes for clogging.
Is the inspection result normal?
YES >> Replace “fuel filter and fuel pump assembly”. Refer to FL-5, "Removal and Installation".
NO >> Repair or replace malfunctioning part.
6.CHECK MASS AIR FLOW SENSOR
WITH CONSULT-III
1. Install all removed parts.
2. Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-III.
For specification, refer to EC-538, "
Mass Air Flow Sensor".
WITH GST
1. Install all removed parts.
2. Check mass air flow sensor signal in Service $01 with GST.
For specification, refer to EC-538, "
Mass Air Flow Sensor".
Is the measurement value within the specification?
YES >> GO TO 7.
NO >> Check connectors for rusted terminals or loose c onnections in the mass air flow sensor circuit or
grounds. Refer to EC-201, "
Diagnosis Procedure".
7.CHECK FUNCTION OF FUEL INJECTOR
DTC A/F sensor 1 ECM
Continuity
Bank Connector Terminal Connector Terminal
P0171 1 F67 3
F110 88
Existed
490
694
P0174 2 F68 378
480
674
DTC A/F sensor 1 ECM
Continuity Continuity
Bank Connector Terminal Connector Terminal
P0171 1 F67 3
F110 88
Existed Not existed
490
694
P0174 2 F68 378
480
674
Revision: 2010 May2011 QX56