2014 NISSAN TEANA engine

EC-7
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P2101 ELECTRIC THROTTLE CONTROL
FUNCTION ..................................................... ..
475
DTC Logic ........................................................... ..475
Diagnosis Procedure .............................................475
Component Inspection ..........................................477
P2118 THROTTLE CONTROL MOTOR ..........478
DTC Logic ........................................................... ..478
Diagnosis Procedure .............................................478
Component Inspection ..........................................479
P2119 ELECTRIC THROTTLE CONTROL
ACTUATOR .................................................... ..
480
DTC Logic ........................................................... ..480
Diagnosis Procedure .............................................480
P2122, P2123 APP SENSOR ...........................482
DTC Logic ........................................................... ..482
Diagnosis Procedure .............................................482
Component Inspection ..........................................484
P2127, P2128 APP SENSOR ...........................485
DTC Logic ........................................................... ..485
Diagnosis Procedure .............................................485
Component Inspection ..........................................486
P2135 TP SENSOR ..........................................488
DTC Logic ........................................................... ..488
Diagnosis Procedure .............................................488
Component Inspection ..........................................490
P2138 APP SENSOR .......................................491
DTC Logic ........................................................... ..491
Diagnosis Procedure .............................................491
Component Inspection ..........................................493
P2610 ECM INTERNAL TIMER .......................494
Description .......................................................... ..494
DTC Logic .............................................................494
Diagnosis Procedure .............................................495
BRAKE PEDAL POSITION SWITCH ...............496
Component Function Check ................................ ..496
Diagnosis Procedure .............................................496
Component Inspection (Brake Pedal Position
Switch) ................................................................ ..
497
COOLING FAN .................................................499
Component Function Check ................................ ..499
Diagnosis Procedure .............................................499
Component Inspection (Cooling Fan Motor) .........501
Component Inspection (C ooling Fan Relay) .........502
ELECTRICAL LOAD SIGNAL ....................... ..503
Description .......................................................... ..503
Component Function Check ..................................503
Diagnosis Procedure .............................................503
FUEL INJECTOR .............................................505
Component Function Check ................................ ..505
Diagnosis Procedure .............................................505
Component Inspection ......................................... ..506
FUEL PUMP ....................................................508
Description .............................................................508
Component Function Check ..................................508
Diagnosis Procedure .............................................508
Component Inspection ...........................................510
IGNITION SIGNAL ..........................................511
Component Function Check ..................................511
Diagnosis Procedure .............................................511
Component Inspection (Ignition Coil with Power
Transistor) ........................................................... ..
514
Component Inspection (Condenser) ......................515
INFORMATION DISPLAY (ASCD) .................516
Component Function Check ..................................516
Diagnosis Procedure .............................................516
MALFUNCTION INDICATOR LAMP ..............517
Component Function Check ..................................517
Diagnosis Procedure .............................................517
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) ....................................................
518
Component Function Check ................................ ..518
Diagnosis Procedure .............................................518
Component Inspection ...........................................520
REFRIGERANT PRESSURE SENSOR ..........523
Component Function Check ..................................523
Diagnosis Procedure .............................................523
SENSOR POWER SUPPLY 2 CIRCUIT .........525
Description .............................................................525
Diagnosis Procedure .............................................525
SYMPTOM DIAGNOSIS ............................527
ENGINE CONTRO L SYSTEM ........................527
Symptom Table ................................................... ..527
INFORMATION DISPLAY IS MALFUNCTION-
ING ..................................................................
532
Diagnosis Procedure ........................................... ..532
NORMAL OPERATING CONDITION .............533
Description .............................................................533
PERIODIC MAINTENANCE ......................534
IDLE SPEED .... ...............................................534
Inspection ............................................................ ..534
IGNITION TIMING ...........................................535
Inspection ..............................................................535
EVAPORATIVE EMISSION SYSTEM .............536
Inspection ..............................................................536
EVAP LEAK CHECK ......................................537
Inspection ..............................................................537
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM

EC-8
POSITIVE CRANKCASE VENTILATION ........539
Inspection ............................................................ ..539
REMOVAL AND INSTALLATION ..............540
ECM ................................................................ .540
Removal and Installation ..................................... ..540
SERVICE DATA AND SPECIFICATIONS
(SDS) .............. ............................................
541
SERVICE DATA AND SPECIFICATIONS
(SDS) ............................................................... .
541
Idle Speed ........................................................... ..541
Ignition Timing .......................................................541
Calculated Load Value ..........................................541
Mass Air Flow Sensor ............................................541
VQ35DE
PRECAUTION .............. ..............................
542
PRECAUTIONS .............................................. .542
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. ..
542
On Board Diagnostic (OBD) System of Engine
and CVT .............................................................. ..
542
General Precautions ..............................................543
PREPARATION ..........................................546
PREPARATION .............................................. .546
Special Service Tools .......................................... ..546
Commercial Service Tools .....................................546
SYSTEM DESCRIPTION ...........................548
COMPONENT PARTS .................................... .548
ENGINE CONTROL SYSTEM .................................548
ENGINE CONTROL SYSTEM : Component Parts
Location ............................................................... ..
548
Accelerator Pedal Position Sensor ........................552
Air Fuel Ratio (A/F) Sensor 1 ................................552
ASCD Steering Switch ...........................................553
Battery Current Sensor (With Battery Tempera-
ture Sensor) ......................................................... ..
553
Camshaft Position Sensor (PHASE) .....................554
Cooling Fan ......................................................... ..554
Crankshaft Position Sensor (POS) ........................554
ECM .......................................................................555
Electric Throttle Control Actuator ......................... ..555
Electronic Controlled Engine Mount .................... ..556
Engine Coolant Temperature Sensor ....................556
Engine Oil Pressure Sensor ................................ ..557
Engine Oil Temperature Sensor ............................557
EVAP Canister ..................................... ..................557
EVAP Canister Purge Volu me Control Solenoid
Valve .................................................................... ..
557
EVAP Canister Vent Control Valve ........................558
EVAP Control System Pressu re Sensor ................558
Fuel Injector ......................................................... .558
Fuel Level Sensor Unit and Fuel Pump (With Fuel
Tank Temperature Sensor) .................................. .
558
Heated Oxygen Sensor 2 ......................................559
Ignition Coil (With Power Transistor) ....................560
Intake Valve Timing Control Solenoid Valve .........560
Knock Sensor ....................................................... .560
Malfunction Indicator lamp (MIL) ...........................560
Mass Air Flow Sensor (With Intake Air Tempera-
ture Sensor) ......................................................... .
560
Oil Pressure Warning Lamp ..................................561
Power Valve Actuator 1 and 2 ..............................561
Refrigerant Pressure Sensor ................................562
Stop Lamp Switch & Brak e Pedal Position Switch .562
VIAS Control Solenoid Valve 1 and 2 .................. .562
STRUCTURE AND OPERATION .....................563
Positive Crankcase Ventilation (PCV) ...................563
On Board Refueling Vapor Recovery (ORVR) ..... .564
SYSTEM ...........................................................565
ENGINE CONTROL SYSTEM ................................ .565
ENGINE CONTROL SYSTEM : System Descrip-
tion ....................................................................... .
565
ENGINE CONTROL SYSTEM : Fail-safe .............566
MULTIPORT FUEL INJECTION SYSTEM ............. .568
MULTIPORT FUEL INJECTION SYSTEM : Sys-
tem Description .................................................... .
568
ELECTRIC IGNITION SYSTEM ............................. .571
ELECTRIC IGNITION SYSTEM : System De-
scription ................................................................ .
571
AIR CONDITIONING CUT CONTROL ................... .572
AIR CONDITIONING CUT CONTROL : System
Description ........................................................... .
573
AUTOMATIC SPEED CONTROL DEVICE (ASCD) .574
AUTOMATIC SPEED CONTROL DEVICE (AS-
CD) : System Description ..................................... .
574
COOLING FAN CONTROL .................................... .575
COOLING FAN CONTROL : System Description .575
ELECTRONIC CONTROLLED ENGINE MOUNT .. .577
ELECTRONIC CONTROLLED ENGINE MOUNT
: System Description ............................................ .
577
EVAPORATIVE EMISSION SYSTEM .....................579
EVAPORATIVE EMISSION SYSTEM : System
Description ........................................................... .
580
THROTTLE CONTROL ...........................................581
THROTTLE CONTROL : Syst em Description ......581
INTAKE VALVE TIMING CONTROL ..................... .582
INTAKE VALVE TIMING CONTROL : System De-
scription ................................................................ .
583
ENGINE PROTECTION CONTROL AT LOW EN-
GINE OIL PRESSURE ........................................... .
583
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EC-9
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ENGINE PROTECTION CO
NTROL AT LOW EN-
GINE OIL PRESSURE : System Description ...... ..
583
FUEL FILLER CAP WARNING SYSTEM ............. ..584
FUEL FILLER CAP WARNING SYSTEM : System
Description .......................................................... ..
585
VARIABLE INDUCTION AIR SYSTEM ...................586
VARIABLE INDUCTION AIR SYSTEM : System
Description .......................................................... ..
586
INTEGRATED CONTROL OF ENGINE, CVT, AND
ABS ........................................................................ ..
587
INTEGRATED CONTROL OF ENGINE, CVT,
AND ABS : System Descri ption ............................
588
ALTERNATOR POWER GENERATION VOLT-
AGE VARIABLE CONTROL SYSTEM .................. ..
588
ALTERNATOR POWER GENERATION VOLT-
AGE VARIABLE CONTRO L SYSTEM : System
Description .......................................................... ..
588
CAN COMMUNICATION ....................................... ..588
CAN COMMUNICATION : System Description ....588
OPERATION ................................................... ..589
AUTOMATIC SPEED CONTROL DEVICE (ASCD) ..589
AUTOMATIC SPEED CONT ROL DEVICE (AS-
CD) : Switch Name and Function ........................ ..
589
ON BOARD DIAGNOSTIC (OBD) SYSTEM ....590
Diagnosis Description ......................................... ..590
GST (Generic Scan Tool) ......................................590
DIAGNOSIS SYSTEM (ECM) ...........................591
DIAGNOSIS DESCRIPTION ................................. ..591
DIAGNOSIS DESCRIPTION : 1st Trip Detection
Logic and Two Trip Detection Logic .................... ..
591
DIAGNOSIS DESCRIPTION : DTC and Freeze
Frame Data ......................................................... ..
591
DIAGNOSIS DESCRIPTION : Counter System ....592
DIAGNOSIS DESCRIPTION : Driving Pattern ......595
DIAGNOSIS DESCRIPTION : System Readiness
Test (SRT) Code ................................................. ..
596
DIAGNOSIS DESCRIPTION : Permanent Diag-
nostic Trouble Code (Permanent DTC) ............... ..
597
DIAGNOSIS DESCRIPTION : Malfunction Indica-
tor Lamp (MIL) ..................................................... ..
598
On Board Diagnosis Function ...............................598
CONSULT Function ..............................................601
ECU DIAGNOSIS INFORMATION ............613
ECM ................................................................ ..613
Reference Value ................................................. ..613
Fail-safe ................................................................627
DTC Inspection Priority Chart .............................629
DTC Index ............................................................630
Test Value and Test Limit .....................................634
WIRING DIAGRAM ....................................642
ENGINE CONTRO L SYSTEM ........................642
Wiring Diagram .................................................... ..642
BASIC INSPECTION .................................670
DIAGNOSIS AND REPAIR WORKFLOW ......670
Work Flow ............................................................ ..670
Diagnostic Work Sheet ..........................................673
BASIC INSPECTION .......................................675
Work Procedure .....................................................675
ADDITIONAL SERVICE WHEN REPLACING
ECM .................................................................
679
Description ........................................................... ..679
Work Procedure .....................................................679
ACCELERATOR PEDAL RELEASED POSI-
TION LEARNING ............................................
681
Description ........................................................... ..681
Work Procedure .....................................................681
THROTTLE VALVE CLOSED POSITION
LEARNING ....... ...............................................
682
Description ........................................................... ..682
Work Procedure .....................................................682
IDLE AIR VOLUME LEARNING .....................683
Description .............................................................683
Work Procedure .....................................................683
MIXTURE RATIO SELF-LEARNING VALUE
CLEAR ............................................................
685
Description ........................................................... ..685
Work Procedure .....................................................685
VIN REGISTRATION .......................................686
Description .............................................................686
Work Procedure .....................................................686
FUEL PRESSURE ...........................................687
Work Procedure .....................................................687
HOW TO SET SRT CODE ..............................689
Description .............................................................689
SRT Set Driving Pattern ........................................690
Work Procedure .....................................................692
HOW TO ERASE PERMANENT DTC ............695
Description .............................................................695
Work Procedure (Group A) ....................................696
Work Procedure (Group B) ....................................698
DTC/CIRCUIT DIAGNOSIS .......................701
TROUBLE DIAGNOSIS - SPECIFICATION
VALUE .............................................................
701
Description ........................................................... ..701
Component Function Check ..................................701
Diagnosis Procedure .............................................702
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EC-12
Diagnosis Procedure .............................................865
P0462, P0463 FUEL LEVEL SENSOR ...........866
DTC Logic ............................................................ ..866
Diagnosis Procedure .............................................866
P0500 VSS .......................................................867
Description ........................................................... ..867
DTC Logic ..............................................................867
Diagnosis Procedure .............................................867
P0506 ISC SYSTEM ........................................869
Description ........................................................... ..869
DTC Logic ..............................................................869
Diagnosis Procedure .............................................869
P0507 ISC SYSTEM ........................................871
Description ........................................................... ..871
DTC Logic ..............................................................871
Diagnosis Procedure .............................................871
P050A, P050E COLD START CONTROL .......873
Description ........................................................... ..873
DTC Logic ..............................................................873
Diagnosis Procedure .............................................874
P0520 EOP SENSOR ......................................875
DTC Logic ............................................................ ..875
Diagnosis Procedure .............................................875
Component Inspection ...........................................877
P0524 ENGINE OIL PRESSURE ....................878
DTC Logic ............................................................ ..878
Diagnosis Procedure .............................................879
Component Inspection ...........................................880
P0603 ECM POWER SUPPLY ........................881
DTC Logic ............................................................ ..881
Diagnosis Procedure .............................................881
P0605 ECM ......................................................883
DTC Logic ............................................................ ..883
Diagnosis Procedure .............................................883
P0607 ECM ......................................................884
DTC Logic ............................................................ ..884
Diagnosis Procedure .............................................884
P0643 SENSOR POWER SUPPLY .................885
Description ........................................................... ..885
DTC Logic ..............................................................885
Diagnosis Procedure .............................................885
P0850 PNP SWITCH .......................................887
Description ........................................................... ..887
DTC Logic ..............................................................887
Component Function Check ..................................888
Diagnosis Procedure .............................................888
P1148, P1168 CLOSED LOOP CONTROL .....890
DTC Logic ............................................................ ..890
P1212 TCS COMMUNICATION LINE ..............891
Description ........................................................... .891
DTC Logic .............................................................891
Diagnosis Procedure .............................................891
P1217 ENGINE OVER TEMPERATURE .........892
DTC Logic ............................................................ .892
Component Function Check .................................892
Diagnosis Procedure .............................................893
P1225 TP SENSOR ..........................................895
DTC Logic ............................................................ .895
Diagnosis Procedure .............................................895
P1226 TP SENSOR ..........................................896
DTC Logic ............................................................ .896
Diagnosis Procedure .............................................896
P1550 BATTERY CURRENT SENSOR ...........897
DTC Logic ............................................................ .897
Diagnosis Procedure .............................................897
Component Inspection ..........................................898
P1551, P1552 BATTERY CURRENT SEN-
SOR ................................................................ ..
899
DTC Logic ............................................................ .899
Diagnosis Procedure .............................................899
Component Inspection ..........................................900
P1553 BATTERY CURRENT SENSOR ...........901
DTC Logic ............................................................ .901
Diagnosis Procedure .............................................901
Component Inspection ..........................................902
P1554 BATTERY CURRENT SENSOR ...........903
DTC Logic ............................................................ .903
Component Function Check .................................903
Diagnosis Procedure .............................................903
Component Inspection ..........................................904
P1556, P1557 BATTERY TEMPERATURE
SENSOR ......................................................... ..
906
DTC Logic ............................................................ .906
Diagnosis Procedure .............................................906
Component Inspection (Battery Temperature
Sensor) ................................................................ .
907
P1564 ASCD STEERING SWITCH ..................908
DTC Logic ............................................................ .908
Diagnosis Procedure .............................................908
Component Inspection ..........................................910
P1572 ASCD BRAKE SWITCH ........................911
Description ........................................................... .911
DTC Logic .............................................................911
Component Function Check .................................912
Diagnosis Procedure .............................................913
Component Inspection (Brake Pedal Position
Switch) ................................................................. .
916
Component Inspection (Stop Lamp Switch) ..........916
Component Inspection (Stop Lamp Relay) ...........917
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EC-13
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P1574 ASCD VEHICLE SPEED SENSOR .... ..918
Description .......................................................... ..918
DTC Logic .............................................................918
Diagnosis Procedure .............................................918
P1800 VIAS CONTROL SOLENOID VALVE 1 ..920
DTC Logic ........................................................... ..920
Diagnosis Procedure .............................................920
Component Inspection ..........................................921
P1801 VIAS CONTROL SOLENOID VALVE 2 ..922
DTC Logic ........................................................... ..922
Diagnosis Procedure .............................................922
Component Inspection ..........................................923
P1805 BRAKE SWITCH ................................. ..924
Description .......................................................... ..924
DTC Logic .............................................................924
Diagnosis Procedure .............................................924
Component Inspection (Stop Lamp Switch) ..........926
Component Inspection (Stop Lamp Relay) ...........926
P2096, P2097, P2098, P2099 A/F SENSOR 1 ..927
DTC Logic ........................................................... ..927
Diagnosis Procedure .............................................927
P2100, P2103 THROTTLE CONTROL MO-
TOR RELAY ................................................... ..
931
DTC Logic ........................................................... ..931
Diagnosis Procedure .............................................931
P2101 ELECTRIC THROTTLE CONTROL
FUNCTION ..................................................... ..
933
DTC Logic ........................................................... ..933
Diagnosis Procedure .............................................933
Component Inspection ..........................................935
P2118 THROTTLE CONTROL MOTOR ..........936
DTC Logic ........................................................... ..936
Diagnosis Procedure .............................................936
Component Inspection ..........................................937
P2119 ELECTRIC THROTTLE CONTROL
ACTUATOR .................................................... ..
938
DTC Logic ........................................................... ..938
Diagnosis Procedure .............................................938
P2122, P2123 APP SENSOR ...........................940
DTC Logic ........................................................... ..940
Diagnosis Procedure .............................................940
Component Inspection ..........................................941
P2127, P2128 APP SENSOR ...........................942
DTC Logic ........................................................... ..942
Diagnosis Procedure .............................................942
Component Inspection ..........................................943
P2135 TP SENSOR ..........................................945
DTC Logic ........................................................... ..945
Diagnosis Procedure .............................................945
Component Inspection ..........................................946
P2138 APP SENSOR ......................................947
DTC Logic ............................................................ ..947
Diagnosis Procedure .............................................947
Component Inspection ...........................................949
BRAKE PEDAL POSITION SWITCH .............950
Component Function Check ..................................950
Diagnosis Procedure .............................................950
Component Inspection (Brake Pedal Position
Switch) ................................................................. ..
951
ASCD INDICATOR ..........................................952
Component Function Check ..................................952
Diagnosis Procedure .............................................952
COOLING FAN ................................................953
Component Function Check ..................................953
Diagnosis Procedure .............................................953
Component Inspection (Cooling Fan Motor) ..........955
Component Inspection (Cooling Fan Relay) ..........956
ELECTRICAL LOAD SIGNAL ........................957
Description .............................................................957
Component Function Check ..................................957
Diagnosis Procedure .............................................957
ELECTRONIC CONTROLLED ENGINE
MOUNT ............................................................
959
Component Function Check ................................ ..959
Diagnosis Procedure .............................................959
Component Inspection ...........................................960
FUEL INJECTOR ............................................962
Component Function Check ..................................962
Diagnosis Procedure .............................................962
Component Inspection ...........................................963
FUEL PUMP ....................................................965
Component Function Check ..................................965
Diagnosis Procedure .............................................965
Component Inspection ...........................................966
IGNITION SIGNAL ..........................................967
Component Function Check ..................................967
Diagnosis Procedure .............................................967
Component Inspection (Ignition Coil with Power
Transistor) ........................................................... ..
970
Component Inspection (Condenser) ......................971
INFORMATION DISPLAY (ASCD) .................972
Component Function Check ..................................972
Diagnosis Procedure .............................................972
MALFUNCTION INDICATOR LAMP ..............973
Component Function Check ..................................973
Diagnosis Procedure .............................................973
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) ....................................................
974
Component Function Check ................................ ..974
Diagnosis Procedure .............................................974
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EC-14
Component Inspection ...........................................976
REFRIGERANT PRESSURE SENSOR ..........979
Component Function Check ................................ ..979
Diagnosis Procedure .............................................979
SENSOR POWER SUPPLY2 CIRCUIT ...........981
Description ........................................................... ..981
Diagnosis Procedure .............................................981
VARIABLE INDUCTION AIR SYSTEM ...........983
Component Function Check ................................ ..983
Diagnosis Procedure .............................................984
SYMPTOM DIAGNOSIS ............................987
ENGINE CONTROL SYSTEM SYMPTOMS .. .987
Symptom Table ................................................... ..987
NORMAL OPERATING CONDITION ..............991
Description ........................................................... ..991
PERIODIC MAINTENANCE ..................... ..992
IDLE SPEED ................................................... .992
Work Procedure ................................................... ..992
IGNITION TIMING .............................................993
Work Procedure ................................................... .993
EVAP LEAK CHECK ........................................994
Work Procedure ................................................... .994
POSITIVE CRANKCASE VENTILATION .........996
Work Procedure ................................................... .996
REMOVAL AND INSTALLATION .............997
ECM ................................................................ ..997
Removal and Installation .......................................997
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... ..........................................
998
SERVICE DATA AND SPECIFICATIONS
(SDS) .............................................................. ..
998
Idle Speed ............................................................ .998
Ignition Timing .......................................................998
Calculated Load Value ..........................................998
Mass Air Flow Sensor ...........................................998
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PRECAUTIONSEC-15
< PRECAUTION > [QR25DE]
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental
Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000009951805
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. Information necessary to service t he system safely is included in the SR and SB section of
this Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery and wait at least three mi nutes before performing any service.
Precaution for Procedure without Cowl Top CoverINFOID:0000000009462048
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc to prevent damage to
windshield.
On Board Diagnostic (OBD) S ystem of Engine and CVTINFOID:0000000009462049
The ECM has an on board diagnostic system . It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
• Be sure to turn the ignition switch OFF and di sconnect the negative battery cable before any repair
or inspection work. The open/short circuit of re lated switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
• Be sure to connect and lock the connectors secure ly after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
• Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For descripti on and how to disconnect, refer to PG-65, "Description"
.
• Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to li ght up due to the short circuit.
PIIB3706J
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EC-16
< PRECAUTION >[QR25DE]
PRECAUTIONS
• Be sure to connect rubber tubes properly afte
r work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system,
etc.
• Be sure to erase the unnecessary malfunction info rmation (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
General PrecautionsINFOID:0000000009462050
•Always use a 12 volt battery as power source.
• Do not attempt to disconnect battery cables while engine is
running.
• Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
• Before removing parts, turn ig nition switch OFF and then dis-
connect battery ground cable.
• Do not disassemble ECM.
• If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slight ly when the terminal is dis-
connected. However, this is no t an indication of a malfunc-
tion. Do not replace parts b ecause of a slight variation.
• If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
• When connecting or disconnect ing pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM pin
terminal, when connecting pin connectors.
• Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge) volt-
age to develop in coil and co ndenser, thus resulting in dam-
age to ICs.
• Keep engine control system harness at least 10 cm (4 in) away
from adjacent harness, to preven t engine control system mal-
functions due to receiving exter nal noise, degraded operation
of ICs, etc.
• Keep engine control system parts and harness dry.
• Before replacing ECM, perform ECM Terminals and Reference
Value inspection and make sure ECM functions properly.
Refer to EC-88, "Reference Value"
.
• Handle mass air flow sensor carefully to avoid damage.
• Do not clean mass air flow senso r with any type of detergent.
• Do not disassemble electric throttle control actuator.
• Even a slight leak in the ai r intake system can cause serious
incidents.
• Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).
SEF289H
PBIA9222J
PBIB0090E
MEF040D
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM