EC-20
PRECAUTIONS
Revision: 2006 November2007 350Z
Keep engine control system harness at least 10 cm (4 in) away from adjacent harness, to prevent
engine control system malfunctions due to receiving external noise, degraded operation of ICs,
etc.
Keep engine control system parts and harness dry.
Before replacing ECM, perform ECM Terminals and Refer-
ence Value inspection and make sure ECM functions prop-
erly. Refer to EC-103, "
ECM Terminals and Reference Value"
.
Handle mass air flow sensor carefully to avoid damage.
Do not clean mass air flow sensor with any type of deter-
gent.
Do not disassemble electric throttle control actuator.
Even a slight leak in the air intake system can cause seri-
ous incidents.
Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).
After performing each TROUBLE DIAGNOSIS, perform DTC
Confirmation Procedure or Overall Function Check.
The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Overall Function
Check should be a good result if the repair is completed.
When measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.
MEF040D
SEF217U
SEF348N
ON BOARD DIAGNOSTIC (OBD) SYSTEM
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ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
IntroductionNBS0002Z
The ECM has an on board diagnostic system, which detects malfunctions related to engine sensors or actua-
tors. The ECM also records various emission-related diagnostic information including:
The above information can be checked using procedures listed in the table below.
×: Applicable —: Not applicable
*: When DTC and 1st trip DTC simultaneously appear on the display, they cannot be clearly distinguished from each other.
The malfunction indicator lamp (MIL) on the instrument panel lights up when the same malfunction is detected
in two consecutive trips (Two trip detection logic), or when the ECM enters fail-safe mode.
(Refer to EC-89, "
Fail-safe Chart" .)
Two Trip Detection LogicNBS00030
When a malfunction is detected for the 1st time, 1st trip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not light up at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL lights up. The MIL lights up at the same time when the DTC is stored. <2nd
trip> The “trip” in the “Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation. Specific on board diagnostic items will cause the ECM to light up or blink the MIL,
and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
×: Applicable —: Not applicable
When there is an open circuit on MIL circuit, the ECM cannot warn the driver by lighting up MIL when there is
malfunction on engine control system.
Emission-related diagnostic information Diagnostic service
Diagnostic Trouble Code (DTC) Service $03 of SAE J1979
Freeze Frame data Service $02 of SAE J1979
System Readiness Test (SRT) code Service $01 of SAE J1979
1st Trip Diagnostic Trouble Code (1st Trip DTC) Service $07 of SAE J1979
1st Trip Freeze Frame data
Test values and Test limits Service $06 of SAE J1979
Calibration ID Service $09 of SAE J1979
DTC 1st trip DTCFreeze Frame
data1st trip Freeze
Frame dataSRT status SRT code Test value
CONSULT-III××××××—
GST×××—×××
ECM×× *— —×——
ItemsMIL DTC 1st trip DTC
1st trip 2nd trip
1st trip
displaying2nd trip
displaying1st trip
displaying2nd trip
display-
ing BlinkingLighting
upBlinkingLighting
up
Misfire (Possible three way cata-
lyst damage) — DTC: P0300 -
P0306 is being detected×———— —×—
Misfire (Possible three way cata-
lyst damage) — DTC: P0300 -
P0306 is being detected——×——×——
One trip detection diagnoses
(Refer to EC-48, "
EMISSION-
RELATED DIAGNOSTIC INFOR-
MATION ITEMS" .)—×——×———
Except above — — —×—××—
EC-62
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Revision: 2006 November2007 350Z
4. Touch “ERASE”. [The DTC in the TCM (Transmission control module) will be erased.] Then touch “BACK”
twice.
5. Touch “ENGINE”.
6. Touch “SELF-DIAG RESULTS”.
7. Touch “ERASE”. (The DTC in the ECM will be erased.)
WITH GST
The emission related diagnostic information in the ECM can be erased by selecting Service $04 with GST.
NOTE:
If the DTC is not for A/T related items (see EC-8, "
INDEX FOR DTC" ), skip step 2.
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once.
Wait at least 10 seconds and then turn it ON (engine stopped) again.
2. Perform AT- 3 8 , "
HOW TO ERASE DTC (WITH GST)" . (The DTC in the TCM will be erased.)
3. Select Service $04 with GST (Generic Scan Tool).
NO TOOLS
NOTE:
If the DTC is not for A/T related items (see EC-8, "
INDEX FOR DTC" ), skip step 2.
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once.
Wait at least 10 seconds and then turn it ON (engine stopped) again.
2. Perform AT- 3 8 , "
HOW TO ERASE DTC (NO TOOLS)" . (The DTC in the TCM will be erased.)
3. Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal.
Refer to EC-63, "
HOW TO SWITCH DIAGNOSTIC TEST MODE" .
If the battery is disconnected, the emission-related diagnostic information will be lost within 24
hours.
The following data are cleared when the ECM memory is erased.
–Diagnostic trouble codes
–1st trip diagnostic trouble codes
–Freeze frame data
–1st trip freeze frame data
–System readiness test (SRT) codes
–Test values
Actual work procedures are explained using a DTC as an example. Be careful so that not only the DTC, but all
of the data listed above, are cleared from the ECM memory during work procedures.
Malfunction Indicator Lamp (MIL)NBS00032
DESCRIPTION
The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned ON with-
out the engine running. This is a bulb check.
If the MIL does not light up, refer to DI-56, "
WARNING LAMPS" ,
or see EC-716, "
MIL AND DATA LINK CONNECTOR" .
2. When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.
ON BOARD DIAGNOSTIC SYSTEM FUNCTION
The on board diagnostic system has the following three functions.
SEF217U
ON BOARD DIAGNOSTIC (OBD) SYSTEM
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When there is an open circuit on MIL circuit, the ECM cannot warn the driver by lighting up MIL when there is
malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as
NG for 5 trips, ECM warns the driver that engine control system malfunctions and MIL circuit is open by means
of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MIL circuit are detected and demands the
driver to repair the malfunction.
MIL Flashing Without DTC
When any SRT codes are not set, MIL may flash without DTC. For the details, refer to EC-56, "How to Display
SRT Status" .
HOW TO SWITCH DIAGNOSTIC TEST MODE
NOTE:
It is better to count the time accurately with a clock.
It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit
has a malfunction.
Always ECM returns to Diagnostic Test Mode I after ignition switch is turned OFF.
How to Set Diagnostic Test Mode II (Self-diagnostic Results)
1. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quickly 5 times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MIL starts
blinking.
Diagnostic Test
ModeKEY and ENG.
StatusFunction Explanation of Function
Mode I Ignition switch in
ON position
Engine stoppedBULB CHECK This function checks the MIL bulb for damage (blown,
open circuit, etc.).
If the MIL does not come on, check MIL circuit.
Engine running MALFUNCTION
WARNINGThis is a usual driving condition. When a malfunction is
detected twice in two consecutive driving cycles (two trip
detection logic), the MIL will light up to inform the driver
that a malfunction has been detected.
The following malfunctions will light up or blink the MIL in
the 1st trip.
Misfire (Possible three way catalyst damage)
One trip detection diagnoses
Mode II Ignition switch in
ON position
Engine stoppedSELF-DIAGNOSTIC
RESULTSThis function allows DTCs and 1st trip DTCs to be read.
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
BASIC SERVICE PROCEDURE
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7. CHECK TARGET IDLE SPEED AGAIN
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-III.
Refer to EC-76, "
IDLE SPEED" .
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. Refer to EC-76, "
IDLE SPEED" .
OK or NG
OK >> GO TO 10.
NG >> GO TO 8.
8. DETECT MALFUNCTIONING PART
Check the following.
Check camshaft position sensor (PHASE) and circuit.
Refer to EC-394, "
DTC P0340, P0345 CMP SENSOR (PHASE)" .
Check crankshaft position sensor (POS) and circuit.
Refer to EC-386, "
DTC P0335 CKP SENSOR (POS)" .
OK or NG
OK >> GO TO 9.
NG >> 1. Repair or replace.
2. GO TO 4.
9. CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is a rare case.)
2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.
Refer to BL-150, "
NVIS (NISSAN VEHICLE IMMOBILIZER SYSTEM-NATS)" .
>> GO TO 4.
10. CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light.
Refer to EC-76, "
IGNITION TIMING" .
OK or NG
OK >> GO TO 19.
NG >> GO TO 11.A/T: 650 ± 50 rpm (in P or N position)
M/T: 650 ± 50 rpm (in Neutral position)
A/T: 650 ± 50 rpm (in P or N position)
M/T: 650 ± 50 rpm (in Neutral position)
A : Timing indicator
A/T: 15 ± 5° BTDC (in P or N position)
M/T: 15 ± 5° BTDC (in Neutral position)
PBIB3530E
EC-74
BASIC SERVICE PROCEDURE
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11 . PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
>> GO TO 12.
12. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-77, "
Throttle Valve Closed Position Learning" .
>> GO TO 13.
13. PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-77, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 14.
No >> 1. Follow the instruction of Idle Air Volume Learning.
2. GO TO 4.
14. CHECK TARGET IDLE SPEED AGAIN
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-III.
Refer to EC-76, "
IDLE SPEED" .
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. Refer to EC-76, "
IDLE SPEED" .
OK or NG
OK >> GO TO 15.
NG >> GO TO 17.
15. CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light.
Refer to EC-76, "
IGNITION TIMING" .
OK or NG
OK >> GO TO 19.
NG >> GO TO 16.A/T: 650 ± 50 rpm (in P or N position)
M/T: 650 ± 50 rpm (in Neutral position)
A/T: 650 ± 50 rpm (in P or N position)
M/T: 650 ± 50 rpm (in Neutral position)
A : Timing indicator
A/T: 15 ± 5° BTDC (in P or N position)
M/T: 15 ± 5° BTDC (in Neutral position)
PBIB3530E
EC-76
BASIC SERVICE PROCEDURE
Revision: 2006 November2007 350Z
Idle Speed and Ignition Timing CheckNBS00035
IDLE SPEED
With CONSULT-III
Check idle speed in “DATA MONITOR” mode with CONSULT-III.
With GST
Check idle speed in Service $01 with GST.
IGNITION TIMING
1. Attach timing light to loop wire as shown.
2. Check ignition timing.
Procedure After Replacing ECMNBS006SZ
When replacing ECM, the following procedure must be performed.
1. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs. Refer to
BL-152, "
ECM Re-communicating Function" .
2. Perform EC-76, "
VIN Registration" .
3. Perform EC-76, "
Exhaust Valve Timing Control Learning" .
4. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
5. Perform EC-77, "
Throttle Valve Closed Position Learning" .
6. Perform EC-77, "
Idle Air Volume Learning" .
VIN RegistrationNBS00037
DESCRIPTION
VIN Registration is an operation to registering VIN in ECM. It must be performed each time ECM is replaced.
NOTE:
Accurate VIN which is registered in ECM may be required for Inspection & Maintenance (I/M).
OPERATION PROCEDURE
With CONSULT-III
1. Check the VIN of the vehicle and note it. Refer to GI-46, "IDENTIFICATION INFORMATION" .
2. Turn ignition switch ON and engine stopped.
3. Select “VIN REGISTRATION” in “WORK SUPPORT” mode.
4. Follow the instruction of CONSULT-III display.
Exhaust Valve Timing Control LearningNBS00038
DESCRIPTION
Exhaust Valve Timing Control Learning is an operation to learn the characteristic of exhaust valve timing con-
trol magnet retarder by comparing the target angle of exhaust camshaft with the actual retarded angle of
exhaust camshaft. It must be performed each time exhaust valve timing control magnet retarder is discon-
nected or replaced, or ECM is replaced.
1. Loop wire
A. Timing light B. Timing indicator
PBIB3526E
EC-78
BASIC SERVICE PROCEDURE
Revision: 2006 November2007 350Z
Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.
Battery voltage: More than 12.9V (At idle)
Engine coolant temperature: 70 - 100°C (158 - 212°F)
Park/neutral position (PNP) switch: ON
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 be illuminated.
Steering wheel: Neutral (Straight-ahead position)
Vehicle speed: Stopped
Transmission: Warmed-up
–For A/T models with CONSULT-III
Drive vehicle until “ATF TEMP SE 1” in “DATA MONITOR” mode of “A/T” system indicates less than 0.9V.
–For A/T models without CONSULT-III and M/T models
Drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-III
1. Perform EC-77, "Accelerator Pedal Released Position Learning" .
2. Perform EC-77, "
Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-III screen. If “CMPLT” is not displayed, Idle Air Vol-
ume Learning will not be carried out successfully. In this case, find the cause of the incident by referring to
the DIAGNOSIS PROCEDURE below.
8. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the
specifications.
Without CONSULT-III
NOTE:
It is better to count the time accurately with a clock.
It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit
has a malfunction.
1. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
2. Perform EC-77, "
Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quickly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
ITEM SPECIFICATION
Idle speed A/T: 650 ± 50 rpm (in P or N position)
M/T: 650 ± 50 rpm (in Neutral position)
Ignition timing A/T: 15 ± 5° BTDC (in P or N position)
M/T: 15 ± 5° BTDC (in Neutral position)