Page 536 of 3051

22 CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of a problem, but this is rarely
the case.)
2. Perform initialization of NATS system and registration of all NATS ignition key IDs. Refer to ªNATS (Nissan Anti-Theft
System)º, EC-72.
©GO TO 23.
23 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-57.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 19.
INCMP©Follow the construction of ªIdle Air Volume Leaningº.
24 CHECK IGNITION TIMING-II
1. Stop engine.
2. Reconnect throttle position sensor harness connector.
3. Start engine and let it idle.
4. Check ignition timing at idle using a timing light.
SEF984U
Ignition timing:
8±2É BTDC
OK or NG
OK (With CONSULT-II)©GO TO 32.
OK (Without CONSULT-
II)©GO TO 35.
NG©GO TO 25.
25 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-57.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 26.
INCMP©Follow the construction of ªIdle Air Volume Learningº.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG18DE
Basic Inspection (Cont'd)
EC-111
Page 537 of 3051

26 CHECK IGNITION TIMING AGAIN
Check ignition timing again. Refer to Test No. 24.
OK or NG
OK (With CONSULT-II)©GO TO 32.
OK (Without CONSULT-
II)©GO TO 35.
NG©GO TO 27.
27 CHECK FOR INTAKE AIR LEAK
1. Start engine and let it idle.
2. Listen for an air leak from PCV hose and after IACV-AAC valve.
OK or NG
OK©GO TO 29.
NG©GO TO 28.
28 REPAIR MALFUNCTION
1. Stop engine.
2. Repair or replace malfunctioning part.
©GO TO 25.
29 DETECT MALFUNCTIONING PART
Check the IACV-AAC valve circuit and function. Refer to EC-343.
OK or NG
OK©GO TO 31.
NG©GO TO 30.
30 REPAIR MALFUNCTION
Repair or replace malfunction part following the ªDiagnostic Procedureº corresponding the detected malfunction.
©GO TO 25.
31 CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function.
(ECM may be the cause of a problem, but this is rarely the case.)
2. Perform initialization of NATS system and registration of NATS ignition key IDs. Refer to ªNATS (Nissan Anti-Theft
System)º, EC-72.
©GO TO 25.
32 CHECK TARGET IDLE SPEED
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode.
3. Check idle speed.
700±50 rpm
OK or NG
OK©GO TO 38.
NG©GO TO 33.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG18DE
Basic Inspection (Cont'd)
EC-112
Page 545 of 3051

19 CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of a problem, but this is rarely
the case.)
2. Perform initialization of NATS system and registration of NATS ignition key IDs. Refer to ªNATS (Nissan Anti-Theft
system)º, EC-72
©GO TO 14.
20 CHECK IGNITION TIMING
1. Start engine and warm it up to normal operating temperature.
2. Perform initialization of NATS system and registration of NATS ignition key IDs. Refer to ªNATS (Nissan Anti-Theft
System)º, EC-72.
SEM872F
Ignition timing: 8ɱ5É BTDC
OK©GO TO 28.
NG©GO TO 21.
21 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM section.
OK or NG
OK©GO TO 19.
NG©1. Repair the timing chain installation.
2. GO TO 14..
22 CHECK IGNITION TIMING
1. Start engine and let it idle.
2. Check ignition timing at idle using a timing light.
SEM872F
Ignition timing: 8ɱ5É BTDC
OK©GO TO 28.
NG©GO TO 23.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG18DE
Basic Inspection (Cont'd)
EC-120
Page 546 of 3051

23 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-57.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 24.
INCMP©1. Follow the construction of ªIdle Air Volume Leaningº.
2. GO TO 23.
24 CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode with CONSULT-II.
3. Check idle speed.
700±50 rpm
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
700±50 rpm
OK or NG
OK©GO TO 26.
NG©GO TO 25.
25 CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of a problem, but this is rarely
the case).
2. Perform initialization of NATS system and registration of NATS ignition key IDs. Refer to ªNATS (Nissan Anti-Theft
System)º, EC-72.
©GO TO 23.
26 CHECK IGNITION TIMING AGAIN
Check ignition timing again. Refer to Test No. 22.
OK©GO TO 28.
NG©GO TO 27.
27 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM section.
OK or NG
OK©GO TO 25.
NG©1. Repair the timing chain installation.
2. GO TO 23.
28 ERASE UNNECESSARY DTC
After this inspection, unnecessary DTC No. might be displayed.
Erase the stored memory in ECM.
Refer to ªHOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATIONº, EC-71
©INSPECTION END
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG18DE
Basic Inspection (Cont'd)
EC-121
Page 784 of 3051
Diagnostic Procedure=NLEC0298
1 INSPECTION START
With CONSULT-II
1. Turn ignition switch ªONº.
2. Select ªSELF DIAG RESULTSº mode with CONSULT-II.
3. Touch ªERASEº.
4. Perform ªDTC Confirmation Procedureº.
See EC-358.
5. Is the 1st trip DTC P0605 displayed again?
With GST
1. Turn ignition switch ªONº.
2. Select MODE 4 with GST.
3. Touch ªERASEº.
4. Perform ªDTC Confirmation Procedureº.
See EC-358.
5. Is the 1st trip DTC P0605 displayed again?
YesorNo
Ye s©GO TO 2.
No©INSPECTION END
2 REPLACE ECM
1. Replace ECM.
2. Perform initialization of NATS (NISSAN ANTI-THEFT SYSTEM) system and registration of all NATS ignition key IDs.
Refer to ªNATS (NISSAN ANTI-THEFT SYSTEM)º, EC-72.
3. Perform ªIdle Air Volume Learningº, EC-57,
Is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©INSPECTION END
INCMP©Follow the construction of ªIdle Air Volume Learningº.
DTC P0605 ECMQG18DE
Diagnostic Procedure
EC-359
Page 1023 of 3051

registration of all NATS ignition key IDs must be carried
out with CONSULT-II using NATS program card.
Therefore, be sure to receive all keys from vehicle owner.
Regarding the procedure of NATS initialization and NATS
ignition key ID registration, refer to CONSULT-II operation
manual, NATS.
Malfunction Indicator (MI)
DESCRIPTIONNLEC1363
SAT652J
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without the engine running. This is a bulb check.
+If the MI does not light up, refer to EL-156, ªWARNING LAMPSº or see EC-1060.
2. When the engine is started, the MI should go off.
If the MI remains on, the on board diagnostic system has detected an engine system malfunction.
On Board Diagnostic System FunctionNLEC1363S01The on board diagnostic system has the following four functions.
Diagnostic Test Mode I
1. BULB CHECK:
This function checks the MI bulb for damage (blown, open circuit, etc.).
If the MI does not come on, check MI circuit and ECM test mode selector. (See the following page.)
2. MALFUNCTION WARNING:
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
Diagnostic Test Mode II
3. SELF-DIAGNOSTIC RESULTS:
This function allows DTCs and 1st trip DTCs to be read.
4. HEATED OXYGEN SENSOR 1 MONITOR (FRONT):
This function allows the fuel mixture condition (lean or rich), monitored by heated oxygen sensor 1 (front),
to be read.
MI Flashing without DTC
NLEC1363S0101If the ECM is in Diagnostic Test Mode II, MI may flash when engine is running. In this case, check ECM test
mode following ªHow to Switch Diagnostic Test Modesº.
How to switch the diagnostic test (function) modes, and details of the above functions are described later.
(Refer to EC-600.)
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONSR20DE
NATS (Nissan Anti-theft System) (Cont'd)
EC-598
Page 1061 of 3051

23 DETECT MALFUNCTIONING PART
Check the IACV-AAC valve circuit and function. Refer to EC-863 (Models with Euro-OBD system) or EC-995 (Models with-
out Euro-OBD system).
OK or NG
OK©GO TO 25.
NG©GO TO 24.
24 REPAIR MALFUNCTION
Repair or replace malfunction part following the ªDiagnostic Procedureº corresponding the detected malfunction.
©GO TO 19.
25 CHECK ECM FUNCTION
1. Substitute another known good ECM to check ECM function.
(ECM may be the cause of a problem, but this is rarely the case.)
2. Perform initialization of NATS system and registration of NATS ignition key IDs. Refer to ªNATS (Nissan Anti-theft
System)º, EC-597.
©GO TO 19.
26 CHECK TARGET IDLE SPEED
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode.
3. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 32.
NG©GO TO 27.
27 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-581.
Is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 28.
INCMP©Follow the instruction of ªIdle Air Volume Learningº.
28 CHECK TARGET IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode with CONSULT-II.
3. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 32.
NG©GO TO 21.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONSR20DE
Basic Inspection (Models with Throttle Opener) (Cont'd)
EC-636
Page 1068 of 3051

18 CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode with CONSULT-II.
3. Check idle speed.
750±50 rpm
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
750±50 rpm
OK or NG
OK©GO TO 20.
NG©GO TO 19.
19 CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of a problem, but this is rarely
the case.)
2. Perform initialization of NATS system and registration of NATS ignition key IDs. Refer to ªNATS (Nissan Anti-Theft
system)º, EC-597
©GO TO 14.
20 CHECK IGNITION TIMING
1. Start engine and warm it up to normal operating temperature.
2. Check ignition timing at idle using a timing light.
SEF984U
Ignition timing
15ɱ2É BTDC
OK or NG
OK©GO TO 28.
NG©GO TO 21.
21 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM section.
OK or NG
OK©GO TO 19.
NG©1. Repair the timing chain installation.
2. GO TO 14.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONSR20DE
Basic Inspection (Models without Throttle Opener) (Cont'd)
EC-643