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TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-137
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11 . CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> GO TO 12.
12. CHECK A/F SENSOR 1 FUNCTION
Perform all DTC Confirmation Procedure related with A/F sensor 1.
For DTC P0130, P0150, refer to EC-248, "DTC Confirmation Procedure" .
For DTC P0131, P0151, refer to EC-267, "DTC Confirmation Procedure" .
For DTC P0132, P0152, refer to EC-660, "DTC Confirmation Procedure" .
For DTC P0133, P0153, refer to EC-276, "DTC Confirmation Procedure" .
For DTC P2A00, P2A03, refer to EC-660, "DTC Confirmation Procedure" .
OK or NG
OK >> GO TO 15.
NG >> GO TO 13.
13. CHECK A/F SENSOR 1 CIRCUIT
Perform Diagnostic Procedure according to corresponding DTC.
>> GO TO 14.
14. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> GO TO 15.
15. DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect ECM harness connector. Check pin terminal and connector for damage, and then reconnect it.
>> GO TO 16.
16. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> Detect malfunctioning part according to EC-90, "
Symptom Matrix Chart" .
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EC-138
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Revision: 2006 November2007 350Z
17. CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of "DATA MONITOR" mode, and make sure that the indication is within the
SP value.
OK or NG
OK >>INSPECTION END
NG (More than the SP value)>>GO TO 18.
NG (Less than the SP value)>>GO TO 25.
18. DETECT MALFUNCTIONING PART
1. Check for the cause of large engine friction. Refer to the following.
–Engine oil level is too high
–Engine oil viscosity
–Belt tension of power steering, alternator, A/C compressor, etc. is excessive
–Noise from engine
–Noise from transmission, etc.
2. Check for the cause of insufficient combustion. Refer to the following.
–Valve clearance malfunction
–Intake valve timing control function malfunction
–Camshaft sprocket installation malfunction, etc.
>> Repair or replace malfunctioning part, and then GO TO 30.
19. CHECK INTAKE SYSTEM
Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
Crushed air ducts
Malfunctioning seal of air cleaner element
Uneven dirt of air cleaner element
Improper specification of intake air system
OK or NG
OK >> GO TO 21.
NG >> Repair or replace malfunctioning part, and then GO TO 20.
20. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”, AND “B/FUEL SCHDL”
Select “A/F ALPHA-B1”, “A/F ALPHA-B2”, and “B/FUEL SCHDL” in “SPEC” of "DATA MONITOR" mode, and
make sure that the each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG (“B/FUEL SCHDL” is more, “A/F ALPHA-B1”, “A/F ALPHA-B2” are less than the SP value)>>GO TO 21.
21. DISCONNECT AND RECONNECT MASS AIR FLOW SENSOR HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect mass air flow sensor harness connector. Check pin terminal and connector for damage and
then reconnect it again.
>> GO TO 22.
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TROUBLE DIAGNOSIS - SPECIFICATION VALUE
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22. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> 1. Detect malfunctioning part of mass air flow sensor circuit and repair it.
Refer to EC-197, "
DTC P0101, P010B MAF SENSOR" .
2. GO TO 29.
NG >> GO TO 23.
23. CHECK “MAS A/F SE-B1”, “MAS A/F SE-B2”
Select “MAS A/F SE-B1”, “MAS A/F SE-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
indication is within the SP value.
OK or NG
OK >> GO TO 24.
NG (More than the SP value)>>Replace mass air flow sensor, and then GO TO 29.
24. REPLACE ECM
1. Replace ECM.
2. Perform initialization of NVIS(NATS) system and registration of all NVIS(NATS) ignition key IDs.
Refer to BL-152, "
ECM Re-communicating Function" .
3. Perform EC-76, "
VIN Registration" .
4. Perform EC-76, "
Exhaust Valve Timing Control Learning" .
5. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
6. Perform EC-77, "
Throttle Valve Closed Position Learning" .
7. Perform EC-77, "
Idle Air Volume Learning" .
>> GO TO 29.
25. CHECK INTAKE SYSTEM
Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
Crushed air ducts
Malfunctioning seal of air cleaner element
Uneven dirt of air cleaner element
Improper specification of intake air system
OK or NG
OK >> GO TO 27.
NG >> Repair or replace malfunctioning part, and then GO TO 26.
26. CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of "DATA MONITOR" mode, and make sure that the indication is within the
SP value.
OK or NG
OK >>INSPECTION END
NG (Less than the SP value)>>GO TO 27.
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27. CHECK “MAS A/F SE-B1”, “MAS A/F SE-B2”
Select “MAS A/F SE-B1”, “MAS A/F SE-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
indication is within the SP value.
OK or NG
OK >> GO TO 28.
NG (Less than the SP value)>>Replace mass air flow sensor, and then GO TO 30.
28. CHECK INTAKE SYSTEM
Check for the cause of air leak after the mass air flow sensor. Refer to the following.
Disconnection, looseness, and cracks in air duct
Looseness of oil filler cap
Disconnection of oil level gauge
Open stuck, breakage, hose disconnection, or cracks of PCV valve
Disconnection or cracks of EVAP purge hose, open stuck of EVAP canister purge volume control solenoid
valve
Malfunctioning seal of rocker cover gasket
Disconnection, looseness, or cracks of hoses, such as vacuum hose, connecting to intake air system
parts
Malfunctioning seal of intake air system, etc.
>> GO TO 30.
29. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”, AND “B/FUEL SCHDL”
Select “A/F ALPHA-B1”, “A/F ALPHA-B2”, and “B/FUEL SCHDL” in “SPEC” of "DATA MONITOR" mode, and
make sure that the each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> Detect malfunctioning part according to EC-90, "
Symptom Matrix Chart" .
30. CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of "DATA MONITOR" mode, and then make sure that the indication is
within the SP value.
OK or NG
OK >>INSPECTION END
NG >> Detect malfunctioning part according to EC-90, "
Symptom Matrix Chart" .
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TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT
EC-141
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TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTPFP:00006
DescriptionNBS0003V
Intermittent incidents may occur. In many cases, the malfunction resolves itself (the part or circuit function
returns to normal without intervention). It is important to realize that the symptoms described in the customer's
complaint often do not recur on (1st trip) DTC visits. Realize also that the most frequent cause of intermittent
incidents occurrences is poor electrical connections. Because of this, the conditions under which the incident
occurred may not be clear. Therefore, circuit checks made as part of the standard diagnostic procedure may
not indicate the specific malfunctioning area.
Common intermittent incidents Report Situations
Diagnostic ProcedureNBS0003W
1. INSPECTION START
Erase (1st trip) DTCs.
Refer to EC-61, "
HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION" .
>> GO TO 2.
2. CHECK GROUND TERMINALS
Check ground terminals for corroding or loose connection.
Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3. SEARCH FOR ELECTRICAL INCIDENT
Perform GI-27, "
How to Perform Efficient Diagnosis for an Electrical Incident" , “INCIDENT SIMULATION
TESTS”.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4. CHECK CONNECTOR TERMINALS
Refer to GI-24, "
How to Check Terminal" , “HOW TO PROBE CONNECTORS”, “How to Check Enlarged Con-
tact Spring of Terminal”.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace connector.
STEP in Work Flow Situation
2 The CONSULT-III is used. The SELF-DIAG RESULTS screen shows time data other than [0] or [1t].
3 or 4 The symptom described by the customer does not recur.
5 (1st trip) DTC does not appear during the DTC Confirmation Procedure.
10 The Diagnostic Procedure for PXXXX does not indicate the malfunctioning area.
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EC-142
POWER SUPPLY AND GROUND CIRCUIT
Revision: 2006 November2007 350Z
POWER SUPPLY AND GROUND CIRCUITPFP:24110
Wiring DiagramNBS0003X
TBWT1614E
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POWER SUPPLY AND GROUND CIRCUIT
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Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
24 BR/YECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]
For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]
More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
53 P/L Ignition switch[Ignition switch: OFF]0V
[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
125 R Power supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
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EC-144
POWER SUPPLY AND GROUND CIRCUIT
Revision: 2006 November2007 350Z
TBWT1615E