EC-6
Diagnosis Procedure .............................................408
P0850 PNP SWITCH .......................................410
Description ........................................................... ..410
DTC Logic ..............................................................410
Component Function Check ..................................411
Diagnosis Procedure .............................................411
P1078 EVT CONTROL POSITION SENSOR ..413
DTC Logic ............................................................ ..413
Diagnosis Procedure .............................................413
Component Inspection ...........................................415
P1148 CLOSED LOOP CONTROL .................416
DTC Logic ............................................................ ..416
Diagnosis Procedure .............................................416
P117A AIR FUEL RATIO .................................417
DTC Logic ............................................................ ..417
Diagnosis Procedure .............................................418
P1212 TCS COMMUNICATION LINE .............422
Description ........................................................... ..422
DTC Logic ..............................................................422
Diagnosis Procedure .............................................422
P1217 ENGINE OVER TEMPERATURE .........423
DTC Logic ............................................................ ..423
Component Function Check ..................................423
Diagnosis Procedure .............................................424
P1225 TP SENSOR .........................................426
DTC Logic ............................................................ ..426
Diagnosis Procedure .............................................426
P1226 TP SENSOR .........................................427
DTC Logic ............................................................ ..427
Diagnosis Procedure .............................................427
P1550 BATTERY CURRENT SENSOR ..........428
DTC Logic ............................................................ ..428
Diagnosis Procedure .............................................428
Component Inspection ...........................................429
P1551, P1552 BATTERY CURRENT SEN-
SOR ................................................................. .
431
DTC Logic ............................................................ ..431
Diagnosis Procedure .............................................431
Component Inspection ...........................................432
P1553 BATTERY CURRENT SENSOR ..........434
DTC Logic ............................................................ ..434
Diagnosis Procedure .............................................434
Component Inspection ...........................................435
P1554 BATTERY CURRENT SENSOR ..........437
DTC Logic ............................................................ ..437
Component Function Check ..................................437
Diagnosis Procedure .............................................438
Component Inspection ...........................................439
P1556, P1557 BATTERY TEMPERATURE
SENSOR ......................................................... ..
440
DTC Logic ............................................................ .440
Diagnosis Procedure .............................................440
Component Inspection ..........................................441
P1564 ASCD STEERING SWITCH ..................442
DTC Logic ............................................................ .442
Diagnosis Procedure .............................................442
Component Inspection ..........................................444
P1572 ASCD BRAKE SWITCH ........................445
DTC Logic ............................................................ .445
Diagnosis Procedure .............................................446
Component Inspection (Brake Pedal Position
Switch) ................................................................. .
449
Component Inspection (Stop Lamp Switch) ..........450
Component Inspection (Stop Lamp Relay) ...........450
P1574 ASCD VEHICLE SPEED SENSOR ..... ..452
Description ........................................................... .452
DTC Logic .............................................................452
Diagnosis Procedure .............................................452
P1715 INPUT SPEED SENSOR .......................454
Description ........................................................... .454
DTC Logic .............................................................454
Diagnosis Procedure .............................................454
P1800 INTAKE MANIFOLD TUNING VALVE ..456
DTC Logic .............................................................456
Diagnosis Procedure .............................................456
Component Inspection ..........................................457
P1805 BRAKE SWITCH ................................. ..459
DTC Logic ............................................................ .459
Diagnosis Procedure .............................................459
Component Inspection (Stop Lamp Switch) ..........461
Component Inspection (Stop Lamp Relay) ...........461
P2004 INTAKE MANIFOLD RUNNER CON-
TROL VALVE ................................................. ..
462
DTC Logic ............................................................ .462
Diagnosis Procedure .............................................462
Component Inspection ..........................................463
P2014, P2016, P2017, P2018 INTAKE MANI-
FOLD RUNNER CONTROL VALVE POSI-
TION SENSOR ............................................... ..
465
DTC Logic ............................................................ .465
Diagnosis Procedure .............................................465
P2096, P2097 A/F SENSOR 1 .........................468
DTC Logic ............................................................ .468
Diagnosis Procedure .............................................468
P2100, P2103 THROTTLE CONTROL MO-
TOR RELAY ................................................... ..
472
DTC Logic ............................................................ .472
Diagnosis Procedure .............................................472
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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
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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
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
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
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
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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
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
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
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
PRECAUTIONSEC-17
< PRECAUTION > [QR25DE]
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After performing each TROUBL E DIAGNOSIS, perform DTC
CONFIRMATION PROCEDURE or Component Function
Check. The DTC should not be displayed in the DTC Confir-
mation Procedure if the repair is completed. The Component
Function Check should be a good result if the repair is com-
pleted.
• 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 operate fuel pump when there is no fuel in lines.
• Tighten fuel hose clamps to the specified torque.
• Do not depress accelerator pedal when starting.
• Immediately after starting, do not rev up engine unnecessar-
ily.
• Do not rev up engine ju st prior to shutdown.
JSBIA1315ZZ
SEF348N
SEF709Y
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
EC-22
< SYSTEM DESCRIPTION >[QR25DE]
COMPONENT PARTS
ENGINE COMPARTMENT
Intake manifold runner control valve actuator
EC-31, "Intake Manifold Runner Control Valve"
Electric throttle control actuator
(with built in throttle position sensor and throttle control motor) EC-25, "Electric Thrott
le Control Actuator"
EVAP service port When perform the EVAP leak check, positive pressure is
delivered to the EVAP system through the EVAP service
port.
Refer to EC-537, "Inspection"
.
No. Component Function
JPBIA5840ZZ
Engine rear side Intake side
: Vehicle front
No. Component Function
Exhaust valve timing control position sensor EC-30, "Exhaust Valve Timing Control Position Sensor"
Camshaft position sensor (PHASE)EC-29, "Camshaft Position Sensor (PHASE)"
PCV valveThe positive crankcase ventilation (PCV) valve is provided
to conduct crankcase blow-by gas to the intake manifold.
Fuel injector EC-26, "Fuel Injector"
Crankshaft position sensor (POS)EC-29, "Crankshaft Position Sensor (POS)"
Knock sensorEC-33, "Knock Sensor"
Engine oil temperature sensorEC-33, "Engine Oil Temperature Sensor"
Engine oil pressure sensorEC-33, "Engine Oil Pressure Sensor"
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM