EC-1
ENGINE CONTROL SYSTEM
B ENGINE
CONTENTS
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SECTION EC
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ENGINE CONTROL SYSTEM
INDEX FOR DTC ........................................................ 8
DTC No. Index ......................................................... 8
Alphabetical Index .................................................. 13
PRECAUTIONS ........................................................ 18
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................ 18
Precautions for Battery Service .............................. 18
Precautions for Procedures without Cowl Top Cover ... 18
On Board Diagnostic (OBD) System of Engine and
A/T .......................................................................... 18
Precaution .............................................................. 19
PREPARATION ......................................................... 22
Special Service Tools ............................................. 22
Commercial Service Tools ...................................... 23
ENGINE CONTROL SYSTEM .................................. 24
System Diagram ..................................................... 24
Multiport Fuel Injection (MFI) System .................... 25
Electronic Ignition (EI) System ............................... 27
Fuel Cut Control (at No Load and High Engine
Speed) .................................................................... 28
AIR CONDITIONING CUT CONTROL ..................... 29
Input/Output Signal Chart ....................................... 29
System Description ................................................ 29
AUTOMATIC SPEED CONTROL DEVICE (ASCD) ... 30
System Description ................................................ 30
Component Description .......................................... 31
CAN COMMUNICATION .......................................... 32
System Description ................................................ 32
EVAPORATIVE EMISSION SYSTEM ....................... 33
Description ............................................................. 33
Component Inspection ........................................... 36
Removal and Installation ........................................ 37
How to Detect Fuel Vapor Leakage ....................... 37
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ...................................................................... 39
System Description ................................................ 39
Diagnostic Procedure ............................................. 40
Component Inspection ........................................... 42
POSITIVE CRANKCASE VENTILATION ................. 44Description .............................................................. 44
Component Inspection ............................................ 45
NVIS (NISSAN VEHICLE IMMOBILIZER SYSTEM-
NATS) ........................................................................ 46
Description .............................................................. 46
ON BOARD DIAGNOSTIC (OBD) SYSTEM ............ 47
Introduction ............................................................. 47
Two Trip Detection Logic ........................................ 47
Emission-related Diagnostic Information ................ 48
Malfunction Indicator Lamp (MIL) ........................... 62
OBD System Operation Chart ................................ 65
BASIC SERVICE PROCEDURE ............................... 71
Basic Inspection ..................................................... 71
Idle Speed and Ignition Timing Check .................... 76
Procedure After Replacing ECM ............................ 76
VIN Registration ..................................................... 76
Exhaust Valve Timing Control Learning .................. 76
Accelerator Pedal Released Position Learning ...... 77
Throttle Valve Closed Position Learning ................. 77
Idle Air Volume Learning ........................................ 77
Fuel Pressure Check .............................................. 79
TROUBLE DIAGNOSIS ............................................ 81
Trouble Diagnosis Introduction ............................... 81
DTC Inspection Priority Chart ................................. 87
Fail-safe Chart ........................................................ 89
Symptom Matrix Chart ............................................ 90
Engine Control Component Parts Location ............ 94
Vacuum Hose Drawing .........................................100
Circuit Diagram .....................................................101
ECM Harness Connector Terminal Layout ...........103
ECM Terminals and Reference Value ...................103
CONSULT-III Function (ENGINE) .........................116
Generic Scan Tool (GST) Function .......................125
CONSULT-III Reference Value in Data Monitor ....127
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .132
Description ............................................................132
Testing Condition ..................................................132
Inspection Procedure ............................................132
Diagnostic Procedure ...........................................133
TROUBLE DIAGNOSIS FOR INTERMITTENT INCI-
EC-6Revision: 2006 November2007 350Z On Board Diagnosis Logic ....................................528
DTC Confirmation Procedure ...............................529
Wiring Diagram .....................................................530
Diagnostic Procedure ...........................................534
Component Inspection ..........................................539
Removal and Installation ......................................539
DTC P1148, P1168 CLOSED LOOP CONTROL ....540
On Board Diagnosis Logic ....................................540
DTC P1211 TCS CONTROL UNIT ..........................541
Description ............................................................541
On Board Diagnosis Logic ....................................541
DTC Confirmation Procedure ...............................541
Diagnostic Procedure ...........................................541
DTC P1212 TCS COMMUNICATION LINE ............542
Description ............................................................542
On Board Diagnosis Logic ....................................542
DTC Confirmation Procedure ...............................542
Diagnostic Procedure ...........................................542
DTC P1217 ENGINE OVER TEMPERATURE ........543
Description ............................................................543
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................544
On Board Diagnosis Logic ....................................544
Overall Function Check ........................................545
Wiring Diagram .....................................................547
Diagnostic Procedure ...........................................549
Main 12 Causes of Overheating ...........................555
Component Inspection ..........................................556
DTC P1225, P1234 TP SENSOR ............................557
Component Description ........................................557
On Board Diagnosis Logic ....................................557
DTC Confirmation Procedure ...............................557
Diagnostic Procedure ...........................................558
Removal and Installation ......................................558
DTC P1226, P1235 TP SENSOR ............................559
Component Description ........................................559
On Board Diagnosis Logic ....................................559
DTC Confirmation Procedure ...............................559
Diagnostic Procedure ...........................................560
Removal and Installation ......................................560
DTC P1233, P2101 ELECTRIC THROTTLE CON-
TROL FUNCTION ...................................................561
Description ............................................................561
On Board Diagnosis Logic ....................................561
DTC Confirmation Procedure ...............................561
Wiring Diagram .....................................................562
Diagnostic Procedure ...........................................566
Component Inspection ..........................................570
Removal and Installation ......................................570
DTC P1236, P2118 THROTTLE CONTROL MOTOR .571
Component Description ........................................571
On Board Diagnosis Logic ....................................571
DTC Confirmation Procedure ...............................571
Wiring Diagram .....................................................572
Diagnostic Procedure ...........................................576
Component Inspection ..........................................579
Removal and Installation ......................................579
DTC P1238, P2119 ELECTRIC THROTTLE CON-
TROL ACTUATOR ..................................................580Component Description ........................................580
On Board Diagnosis Logic ....................................580
DTC Confirmation Procedure ................................580
Diagnostic Procedure ............................................581
DTC P1239, P2135 TP SENSOR ............................582
Component Description ........................................582
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................582
On Board Diagnosis Logic ....................................582
DTC Confirmation Procedure ................................583
Wiring Diagram .....................................................584
Diagnostic Procedure ............................................588
Component Inspection ..........................................590
Removal and Installation .......................................591
DTC P1290, P2100, P2103 THROTTLE CONTROL
MOTOR RELAY .......................................................592
Component Description ........................................592
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................592
On Board Diagnosis Logic ....................................592
DTC Confirmation Procedure ................................592
Wiring Diagram .....................................................594
Diagnostic Procedure ............................................597
DTC P1421 COLD START CONTROL ....................600
Description ............................................................600
On Board Diagnosis Logic ....................................600
DTC Confirmation Procedure ................................600
Diagnostic Procedure ............................................600
DTC P1564 ASCD STEERING SWITCH ................602
Component Description ........................................602
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................602
On Board Diagnosis Logic ....................................602
DTC Confirmation Procedure ................................603
Wiring Diagram .....................................................604
Diagnostic Procedure ............................................606
Component Inspection ..........................................609
DTC P1572 ASCD BRAKE SWITCH ......................610
Component Description ........................................610
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................610
On Board Diagnosis Logic ....................................610
DTC Confirmation Procedure ................................611
Wiring Diagram .....................................................612
Diagnostic Procedure ............................................615
Component Inspection ..........................................624
DTC P1574 ASCD VEHICLE SPEED SENSOR .....625
Component Description ........................................625
On Board Diagnosis Logic ....................................625
DTC Confirmation Procedure ................................625
Diagnostic Procedure ............................................626
DTC P1715 INPUT SPEED SENSOR (TURBINE
REVOLUTION SENSOR) ........................................627
Description ............................................................627
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................627
On Board Diagnosis Logic ....................................627
Diagnostic Procedure ............................................627
DTC P1805 BRAKE SWITCH .................................628
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
PREPARATION
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Commercial Service ToolsNBS0002F
Tool name
(Kent-Moore No.)Description
Leak detector
i.e.: (J-41416)Locating the EVAP leak
EVAP service port
adapter
i.e.: (J-41413-OBD)Applying positive pressure through EVAP service
port
Fuel filler cap adapter
i.e.: (MLR-8382)Checking fuel tank vacuum relief valve opening
pressure
Socket wrench Removing and installing engine coolant
temperature sensor
Oxygen sensor thread
cleaner
i.e.: (J-43897-18)
(J-43897-12)Reconditioning the exhaust system threads
before installing a new oxygen sensor. Use with
anti-seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for
Zirconia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for
Titania Oxygen Sensor
Anti-seize lubricant
i.e.: (Permatex
TM
133AR or equivalent
meeting MIL
specification MIL-A-
907)Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
S-NT703
S-NT704
S-NT815
S-NT705
AEM488
S-NT779
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
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ON BOARD REFUELING VAPOR RECOVERY (ORVR)PFP:00032
System DescriptionNBS0002T
From the beginning of refueling, the air and vapor inside the fuel tank go through refueling EVAP vapor cut
valve and EVAP/ORVR line to the EVAP canister. The vapor is absorbed by the EVAP canister and the air is
released to the atmosphere.
When the refueling has reached the full level of the fuel tank, the refueling EVAP vapor cut valve is closed and
refueling is stopped because of auto shut-off. The vapor which was absorbed by the EVAP canister is purged
during driving.
WARNING:
When conducting inspections below, be sure to observe the following:
Put a “CAUTION: FLAMMABLE” sign in workshop.
Do not smoke while servicing fuel system. Keep open flames and sparks away from work area.
Be sure to furnish the workshop with a CO2 fire extinguisher.
CAUTION:
Before removing fuel line parts, carry out the following procedures:
–Put drained fuel in an explosion-proof container and put lid on securely.
–Release fuel pressure from fuel line. Refer to EC-79, "FUEL PRESSURE RELEASE" .
–Disconnect battery ground cable.
Always replace O-ring when the fuel gauge retainer is removed.
Do not kink or twist hose and tube when they are installed.
Do not tighten hose and clamps excessively to avoid damaging hoses.
After installation, run engine and check for fuel leaks at connection.
Do not attempt to top off the fuel tank after the fuel pump nozzle shuts off automatically.
Continued refueling may cause fuel overflow, resulting in fuel spray and possibly a fire.
PBIB1068E
POSITIVE CRANKCASE VENTILATION
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Component InspectionNBS0002X
PCV (POSITIVE CRANKCASE VENTILATION) VALVE
With engine running at idle, remove PCV valve from rocker cover. A
properly working valve makes a hissing noise as air passes through
it. A strong vacuum should be felt immediately when a finger is
placed over valve inlet.
PCV VALVE VENTILATION HOSE
1. Check hoses and hose connections for leaks.
2. Disconnect all hoses and clean with compressed air. If any hose
cannot be freed of obstructions, replace.
PBIB1589E
S-ET277
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 — — —×—××—
ON BOARD DIAGNOSTIC (OBD) SYSTEM
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If the DTC is being detected currently, the time data will be [0].
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-III or
GST. The 1st trip freeze frame data can only be displayed on the CONSULT-III screen, not on the GST. For
details, see EC-119, "
Freeze Frame Data and 1st Trip Freeze Frame Data" .
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM mem-
ory is erased. Procedures for clearing the ECM memory are described in EC-61, "
HOW TO ERASE EMIS-
SION-RELATED DIAGNOSTIC INFORMATION" .
SYSTEM READINESS TEST (SRT) CODE
System Readiness Test (SRT) code is specified in Service $01 of SAE J1979.
As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains
“CMPLT” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
If, during the state emissions inspection, the SRT indicates “CMPLT” for all test items, the inspector will con-
tinue with the emissions test. However, if the SRT indicates “INCMP” for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If MIL is ON during the state emissions inspection, the vehicle is also returned to the customer untested even
though the SRT indicates “CMPLT” for all test items. Therefore, it is important to check SRT (“CMPLT”) and
DTC (No DTCs) before the inspection.
SRT Item
The table below shows required self-diagnostic items to set the SRT to “CMPLT”.
Priority Items
1Freeze frame data Misfire — DTC: P0300 - P0306
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data