2010 INFINITI QX56 fuel

CHG
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM
CHG-7
< FUNCTION DIAGNOSIS >
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POWER GENERATION VOLTAG
E VARIABLE CONTROL SYSTEM
System DiagramINFOID:0000000005146554
System DescriptionINFOID:0000000005146555
Power generation variable voltage control system has been adopted. By varying the voltage to the generator,
engine load due to power generation of the generator is reduced and fuel consumption is decreased.
NOTE:
When any malfunction is detected in the power generat ion variable voltage control system, power generation
is performed according to the characterist ic of the IC regulator in the generator.
Component DescriptionINFOID:0000000005146556
ALMIA0057GB
Component part Description
Battery current sensor The battery current sensor is installed on the battery cable at the
negative terminal. The battery current sensor detects the charg-
ing/discharging current of the battery and sends a voltage signal
to the ECM according to the current value detected.
ECM The battery current sensor detects the charging/discharging cur-
rent of the battery. The ECM judges the battery condition based on
this signal.
The ECM judges whether to request more output via the power
generation voltage variable control according to the battery condi-
tion.
When performing the power generation voltage variable control,
the ECM calculates the target power generation voltage according
to the battery condition and sends the calculated value as the pow-
er generation command value to the IPDM E/R.
IPDM E/R The IPDM E/R converts the received power generation command
value into a pulse width modulated (PWM) command signal and
sends it to the IC regulator.
Generator (IC regulator) The IC regulator controls the power generation voltage by the tar-
get power generation voltage based on the received PWM com-
mand signal.
When there is no PWM command signal, the generator performs
the normal power generation according to the characteristic of the
IC regulator.
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EC-1
ENGINE
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SECTION EC
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CONTENTS
ENGINE CONTROL SYSTEM
VK56DE
BASIC INSPECTION ....... .............................
8
DIAGNOSIS AND REPAIR WORKFLOW ..... .....8
Trouble Diagnosis Introduction ........................... ......8
INSPECTION AND ADJUSTMENT ....................13
Basic Inspection .................................................. ....13
Idle Speed and Ignition Timing Check ....................17
Procedure After Replacing ECM .............................17
VIN Registration ......................................................17
Accelerator Pedal Released Position Learning .......18
Throttle Valve Closed Position Learning .................18
Idle Air Volume Learning .........................................18
FUNCTION DIAGNOSIS ..............................21
ENGINE CONTROL SYSTEM ........................ ....21
System Diagram .................................................. ....21
Engine Control Component Parts Location .............22
MULTIPORT FUEL INJECTION SYSTEM ..... ....28
System Description ............................................. ....28
ELECTRIC IGNITION SYSTEM ..................... ....31
System Description ............................................. ....31
AIR CONDITIONING CUT CONTROL ...............32
Input/Output Signal Chart .................................... ....32
System Description .................................................32
AUTOMATIC SPEED CONTROL DEVICE
(ASCD) ...............................................................
33
System Description ............................................. ....33
Component Description ...........................................34
CAN COMMUNICATION ....................................35
System Description ............................................. ....35
COOLING FAN CONTROL ................................36
Description ..............................................................36
EVAPORATIVE EMISSION SYSTEM ...............37
Description ........................................................... ....37
INTAKE VALVE TIMING CONTROL ................40
Description ...............................................................40
ON BOARD DIAGNOSTIC (OBD) SYSTEM ....41
Introduction ..............................................................41
Two Trip Detection Logic .........................................41
Emission-related Diagnostic Information .................42
Malfunction Indicator Lamp (MIL) ............................55
OBD System Operation Chart .................................58
CONSULT-III Function (ENGINE) ...........................63
Generic Scan Tool (GST) Function .........................72
COMPONENT DIAGNOSIS .........................74
TROUBLE DIAGNOSIS - SPECIFICATION
VALUE ...............................................................
74
Description ........................................................... ....74
Testing Condition .....................................................74
Inspection Procedure ...............................................74
Diagnosis Procedure ...............................................75
POWER SUPPLY AND GROUND CIRCUIT ....82
Diagnosis Procedure ...............................................82
Ground Inspection ...................................................85
U0101 CAN COMM CIRCUIT ...........................86
Description ...............................................................86
On Board Diagnosis Logic .......................................86
DTC Confirmation Procedure ..................................86
Diagnosis Procedure ...............................................86
U1001 CAN COMM CIRCUIT ...........................87
Description ...............................................................87
On Board Diagnosis Logic .......................................87
DTC Confirmation Procedure ..................................87
Diagnosis Procedure ...............................................87
P0011, P0021 IVT CONTROL ...........................88
On Board Diagnosis Logic .......................................88
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EC-3
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Diagnosis Procedure ...........................................
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156
Component Inspection ..........................................158
P0138, P0158 HO2S2 ......................................160
Component Description ....................................... ..160
On Board Diagnosis Logic ....................................160
DTC Confirmation Procedure ................................160
Overall Function Check .........................................161
Diagnosis Procedure .............................................162
Component Inspection ..........................................165
P0139, P0159 HO2S2 ......................................167
Component Description ....................................... ..167
On Board Diagnosis Logic ....................................167
DTC Confirmation Procedure ................................167
Overall Function Check .........................................168
Diagnosis Procedure .............................................168
Component Inspection ..........................................170
P0171, P0174 FUEL INJECTION SYSTEM
FUNCTION .......................................................
172
On Board Diagnosis Logic .................................. ..172
DTC Confirmation Procedure ................................172
Diagnosis Procedure .............................................173
P0172, P0175 FUEL INJECTION SYSTEM
FUNCTION .......................................................
177
On Board Diagnosis Logic .................................. ..177
DTC Confirmation Procedure ................................177
Diagnosis Procedure .............................................178
P0181 FTT SENSOR ........................................182
Component Description ....................................... ..182
On Board Diagnosis Logic ....................................182
DTC Confirmation Procedure ................................182
Diagnosis Procedure .............................................183
Component Inspection ..........................................184
P0182, P0183 FTT SENSOR ...........................185
Component Description ....................................... ..185
On Board Diagnosis Logic ....................................185
DTC Confirmation Procedure ................................185
Diagnosis Procedure .............................................185
Component Inspection ..........................................187
P0222, P0223 APP SENSOR ...........................188
Component Description .........................................188
On Board Diagnosis Logic ....................................188
DTC Confirmation Procedure ................................188
Diagnosis Procedure .............................................188
Component Inspection ..........................................191
P0300, P0301, P0302, P0303, P0304, P0305,
P0306, P0307, P0308 MISFIRE .......................
192
On Board Diagnosis Logic .................................. ..192
DTC Confirmation Procedure ................................192
Diagnosis Procedure .............................................193
P0327, P0328, P0332, P0333 KS ....................198
Component Description ....................................... ..198
On Board Diagnosis Logic ....................................198
DTC Confirmation Procedure .............................. ..198
Diagnosis Procedure .............................................198
Component Inspection ...........................................200
P0335 CKP SENSOR (POS) ...........................201
Component Description .........................................201
On Board Diagnosis Logic .....................................201
DTC Confirmation Procedure ................................201
Diagnosis Procedure .............................................201
Component Inspection ...........................................203
P0340 CMP SENSOR (PHASE) .....................205
Component Description .........................................205
On Board Diagnosis Logic .....................................205
DTC Confirmation Procedure ................................205
Diagnosis Procedure .............................................206
Component Inspection ...........................................207
P0420, P0430 THREE WAY CATALYST
FUNCTION ......................................................
209
On Board Diagnosis Logic ................................... ..209
DTC Confirmation Procedure ................................209
Overall Function Check .........................................210
Diagnosis Procedure .............................................210
P0441 EVAP CONTROL SYSTEM .................213
System Description ................................................213
On Board Diagnosis Logic .....................................213
DTC Confirmation Procedure ................................213
Overall Function Check .........................................214
Diagnosis Procedure .............................................214
P0442 EVAP CONTROL SYSTEM .................218
On Board Diagnosis Logic .....................................218
DTC Confirmation Procedure ................................218
Diagnosis Procedure .............................................219
Component Inspection ...........................................224
P0443 EVAP CANISTER PURGE VOLUME
CONTROL SOLENOID VALVE ......................
225
Description .............................................................225
On Board Diagnosis Logic .....................................225
DTC Confirmation Procedure ................................226
Diagnosis Procedure .............................................227
Component Inspection ...........................................229
P0444, P0445 EVAP CANISTER PURGE
VOLUME CONTROL SOLENOID VALVE ......
231
Description .............................................................231
On Board Diagnosis Logic .....................................231
DTC Confirmation Procedure ................................232
Diagnosis Procedure .............................................232
Component Inspection ...........................................233
P0447 EVAP CANISTER VENT CONTROL
VALVE .............................................................
234
Component Description .........................................234
On Board Diagnosis Logic .....................................234
DTC Confirmation Procedure ................................234
Diagnosis Procedure .............................................234
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EC-4
Component Inspection ...........................................236
P0448 EVAP CANISTER VENT CONTROL
VALVE .............................................................
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Component Description ....................................... ..238
On Board Diagnosis Logic .....................................238
DTC Confirmation Procedure ................................238
Diagnosis Procedure .............................................239
Component Inspection ...........................................240
P0451 EVAP CONTROL SYSTEM PRES-
SURE SENSOR ...............................................
242
Component Description ....................................... ..242
On Board Diagnosis Logic .....................................242
DTC Confirmation Procedure ................................242
Diagnosis Procedure .............................................242
Component Inspection ...........................................243
P0452 EVAP CONTROL SYSTEM PRES-
SURE SENSOR ...............................................
245
Component Description ....................................... ..245
On Board Diagnosis Logic .....................................245
DTC Confirmation Procedure ................................245
Diagnosis Procedure .............................................246
Component Inspection ...........................................248
P0453 EVAP CONTROL SYSTEM PRES-
SURE SENSOR ...............................................
249
Component Description ....................................... ..249
On Board Diagnosis Logic .....................................249
DTC Confirmation Procedure ................................249
Diagnosis Procedure .............................................250
Component Inspection ...........................................253
P0455 EVAP CONTROL SYSTEM ..................254
On Board Diagnosis Logic ................................... ..254
DTC Confirmation Procedure ................................254
Diagnosis Procedure .............................................255
Component Inspection ...........................................260
P0456 EVAP CONTROL SYSTEM ..................261
On Board Diagnosis Logic ................................... ..261
DTC Confirmation Procedure ................................262
Overall Function Check .........................................262
Diagnosis Procedure .............................................263
Component Inspection ...........................................268
P0460 FUEL LEVEL SENSOR ........................269
Component Description ....................................... ..269
On Board Diagnosis Logic .....................................269
DTC Confirmation Procedure ................................269
Diagnosis Procedure .............................................269
P0461 FUEL LEVEL SENSOR ........................271
Component Description ....................................... ..271
On Board Diagnosis Logic .....................................271
Overall Function Check .........................................271
Diagnosis Procedure .............................................272
P0462, P0463 FUEL LEVEL SENSOR ...........273
Component Description ....................................... .273
On Board Diagnosis Logic ....................................273
DTC Confirmation Procedure ................................273
Diagnosis Procedure .............................................273
P0500 VSS ........................................................275
Description ........................................................... .275
On Board Diagnosis Logic ....................................275
DTC Confirmation Procedure ................................275
Overall Function Check .........................................276
Diagnosis Procedure .............................................276
P0506 ISC SYSTEM .........................................277
Description ........................................................... .277
On Board Diagnosis Logic ....................................277
DTC Confirmation Procedure ................................277
Diagnosis Procedure .............................................277
P0507 ISC SYSTEM .........................................279
Description ........................................................... .279
On Board Diagnosis Logic ....................................279
DTC Confirmation Procedure ................................279
Diagnosis Procedure .............................................279
P0550 PSP SENSOR .......................................281
Component Description ....................................... .281
On Board Diagnosis Logic ....................................281
DTC Confirmation Procedure ................................281
Diagnosis Procedure .............................................281
Component Inspection ..........................................283
P0603 ECM POWER SUPPLY .........................284
Component Description ....................................... .284
On Board Diagnosis Logic ....................................284
DTC Confirmation Procedure ................................284
Diagnosis Procedure .............................................284
P0605 ECM .......................................................286
Component Description ....................................... .286
On Board Diagnosis Logic ....................................286
DTC Confirmation Procedure ................................286
Diagnosis Procedure .............................................287
P0607 ECM .......................................................288
Description ........................................................... .288
On Board Diagnosis Logic ....................................288
DTC Confirmation Procedure ................................288
Diagnosis Procedure .............................................288
P0643 SENSOR POWER SUPPLY ..................289
On Board Diagnosis Logic ....................................289
DTC Confirmation Procedure ................................289
Diagnosis Procedure .............................................289
P0850 PNP SWITCH ........................................292
Component Description ........................................292
On Board Diagnosis Logic ....................................292
DTC Confirmation Procedure ................................292
Overall Function Check .........................................292
Diagnosis Procedure .............................................293
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EC-6
On Board Diagnosis Logic .....................................353
DTC Confirmation Procedure ................................353
Diagnosis Procedure .............................................353
Component Inspection ...........................................355
P2100, P2103 THROTTLE CONTROL MO-
TOR RELAY .....................................................
356
Component Description ....................................... ..356
On Board Diagnosis Logic .....................................356
DTC Confirmation Procedure ................................356
Diagnosis Procedure .............................................356
P2101 ELECTRIC THROTTLE CONTROL
FUNCTION .......................................................
359
Description ........................................................... ..359
On Board Diagnosis Logic .....................................359
DTC Confirmation Procedure ................................359
Diagnosis Procedure .............................................359
Component Inspection ...........................................362
P2118 THROTTLE CONTROL MOTOR ..........363
Component Description ....................................... ..363
On Board Diagnosis Logic .....................................363
DTC Confirmation Procedure ................................363
Diagnosis Procedure .............................................363
Component Inspection ...........................................364
P2119 ELECTRIC THROTTLE CONTROL
ACTUATOR .....................................................
365
Component Description ....................................... ..365
On Board Diagnosis Logic .....................................365
DTC Confirmation Procedure ................................365
Diagnosis Procedure .............................................366
P2122, P2123 APP SENSOR ..........................367
Component Description ....................................... ..367
On Board Diagnosis Logic .....................................367
DTC Confirmation Procedure ................................367
Diagnosis Procedure .............................................367
Component Inspection ...........................................369
P2127, P2128 APP SENSOR ..........................370
Component Description ....................................... ..370
On Board Diagnosis Logic .....................................370
DTC Confirmation Procedure ................................370
Diagnosis Procedure .............................................370
Component Inspection ...........................................373
P2135 TP SENSOR .........................................374
Component Description ....................................... ..374
On Board Diagnosis Logic .....................................374
DTC Confirmation Procedure ................................374
Diagnosis Procedure .............................................374
Component Inspection ...........................................377
P2138 APP SENSOR ......................................378
Component Description ....................................... ..378
On Board Diagnosis Logic .....................................378
DTC Confirmation Procedure ................................378
Diagnosis Procedure .............................................379
Component Inspection ......................................... .381
P2A00, P2A03 A/F SENSOR 1 ........................382
Component Description ....................................... .382
On Board Diagnosis Logic ....................................382
DTC Confirmation Procedure ................................382
Diagnosis Procedure .............................................383
ASCD BRAKE SWITCH ...................................388
Component Description ....................................... .388
Diagnosis Procedure .............................................388
Component Inspection ..........................................390
ASCD INDICATOR ...........................................391
Component Description ....................................... .391
Diagnosis Procedure .............................................391
COOLING FAN .................................................392
Diagnosis Procedure ............................................ .392
Component Inspection ..........................................392
ELECTRICAL LOAD SIGNAL ..........................394
Description ........................................................... .394
Diagnosis Procedure .............................................394
FUEL INJECTOR ..............................................396
Component Description ....................................... .396
Diagnosis Procedure .............................................396
Component Inspection ..........................................398
FUEL PUMP .....................................................399
Description ........................................................... .399
Diagnosis Procedure .............................................399
Component Inspection ..........................................402
ICC BRAKE SWITCH ..................................... ..403
Component Description ....................................... .403
Diagnosis Procedure .............................................403
Component Inspection ..........................................405
IGNITION SIGNAL ............................................407
Component Description ....................................... .407
Diagnosis Procedure .............................................407
Component Inspection ..........................................410
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) .....................................................
412
System Description .............................................. .412
Diagnosis Procedure .............................................412
Component Inspection ..........................................414
POSITIVE CRANKCASE VENTILATION .........417
Description ........................................................... .417
Component Inspection ..........................................417
REFRIGERANT PRESSURE SENSOR ...........419
Component Description ....................................... .419
Diagnosis Procedure .............................................419
ECU DIAGNOSIS ......................................422
ECM ................................................................ ..422
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EC-7
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EC A
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CONSULT-lll Reference Va
lue in Data Monitor
Mode ................................................................... ..
422
ECM Harness Connector Terminal Layout ...........425
ECM Terminal and Reference Value ....................425
Wiring Diagram - ENGINE CONTROL SYSTEM - ..435
Fail-Safe Chart .................................................... ..456
DTC Inspection Priority Chart ............................. ..458
DTC Index ........................................................... ..459
Emission-related Diagnostic Information ...............463
SYMPTOM DIAGNOSIS ..... .......................477
ENGINE CONTROL SYSTEM SYMPTOMS .. ..477
Symptom Matrix Chart ........................................ ..477
NORMAL OPERATING CONDITION ...............481
Fuel Cut Control (at No Load and High Engine
Speed) ................................................................. ..
481
PRECAUTION ............................................482
PRECAUTIONS .............................................. ..482
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ..
482
On Board Diagnosis (OBD) System of Engine and
A/T .........................................................................
482
Precaution .............................................................482
PREPARATION .........................................486
PREPARATION .............................................. ..486
Special Service Tool ........................................... ..486
Commercial Service Tool ......................................487
ON-VEHICLE MAINTENANCE ..................489
FUEL PRESSURE ...........................................489
Fuel Pressure Check ........................................... ..489
EVAP LEAK CHECK ......................................491
How to Detect Fuel Vapor Leakage .......................491
ON-VEHICLE REPAIR ...............................493
EVAP CANISTER ............................................493
Removal and Installation ..................................... ..493
Component Inspection ...........................................493
INTAKE VALVE TIMING CONTROL ..............494
Intake Valve Timing Control Solenoid Valve (LH) ..494
Intake Valve Timing Cont rol Solenoid Valve (RH) ..494
Intake Valve Timing Control Position Sensor (LH) ..495
Intake Valve Timing Control Position Sensor (RH) ..495
Camshaft Position Sensor (PHASE) .....................495
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .......................................... .
497
SERVICE DATA AND SPECIFICATIONS
(SDS) ...............................................................
497
Fuel Pressure ...................................................... ..497
Idle Speed and Ignition Timing ..............................497
Calculated Load Value ..........................................497
Mass Air Flow Sensor ............................................497
Intake Air Temperature Sensor .............................497
Engine Coolant Temperature Sensor ....................497
A/F Sensor 1 Heater ..............................................497
Heated Oxygen sensor 2 Heater ...........................498
Crankshaft Position Sensor (POS) ........................498
Camshaft Position Sensor (PHASE) .....................498
Throttle Control Motor ............................................498
Fuel Injector ...........................................................498
Fuel Pump .............................................................498
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EC-8
< BASIC INSPECTION >[VK56DE]
DIAGNOSIS AND REPAIR WORKFLOW
BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Trouble Diagnosis IntroductionINFOID:0000000005149054
INTRODUCTION
The engine has an ECM to control major systems such as fuel con-
trol, ignition control, idle air control system, etc. The ECM accepts
input signals from sensors and instantly drives actuators. It is essen-
tial that both input and output signals are proper and stable. At the
same time, it is important that there are no malfunctions such as vac-
uum leaks, fouled spark plugs, or
other malfunctions with the engine.
It is much more difficult to diagnose an incident that occurs intermit-
tently rather than continuously. Most intermittent incidents are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.
A visual check only may not find the cause of the incidents. A road
test with CONSULT-III (or GST) or a circuit tester connected should
be performed. Follow the Work Flow on "WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such incidents, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A Di agnostic Worksheet like the example
on "Worksheet Sample" should be used.
Start your diagnosis by looking fo r conventional malfunctions first.
This will help troubleshoot driveability malfunctions on an electroni-
cally controlled engine vehicle.
WORK FLOW
MEF036D
SEF233G
SEF234G
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EC-10
< BASIC INSPECTION >[VK56DE]
DIAGNOSIS AND REPAIR WORKFLOW
2.CHECK DTC*1
1. Check DTC*1 .
2. Perform the following procedure if DTC*
1 is displayed.
- Record DTC*
1 and freeze frame data*2 . (Print them out with CONSULT-III or GST.)
- Erase DTC*
1 . (Refer to EC-459, "DTC Index" .)
- Study the relationship between the cause detected by DTC*
1 and the symptom described by the cus-
tomer. (Symptom Matrix Chart is useful. Refer to EC-477, "
Symptom Matrix Chart" .)
3. Check related service bulletins for information.
Is any symptom described and any DTC detected?
Symptom is described, DTC*1 is displayed>>GO TO 3.
Symptom is described, DTC*
1 is not displayed>>GO TO 4.
Symptom is not described, DTC*
1 is displayed>>GO TO 5.
3.CONFIRM THE SYMPTOM
Try to confirm the symptom described by the customer (except MIL ON).
DIAGNOSIS WORK SHEET is useful to verify the incident.
Connect CONSULT-III to the vehicle and check real time diagnosis results.
Verify relation between the symptom and the condition when the symptom is detected.
>> GO TO 5.
4.CONFIRM THE SYMPTOM
Try to confirm the symptom described by the customer.
DIAGNOSIS WORK SHEET is useful to verify the incident.
Connect CONSULT-III to the vehicle and check real time diagnosis results.
Verify relation between the symptom and the condition when the symptom is detected.
>> GO TO 6.
5.PERFORM DTC CONFIRMATION PROCEDURE
Perform DTC Confirmation Procedure for the displayed DTC* , and then make sure that DTC*
1 is detected
again.
If two or more DTCs*
1 are detected, refer to EC-458, "DTC Inspection Priority Chart" and determine trouble
diagnosis order.
NOTE:
• Freeze frame data*
2 is useful if the DTC*1 is not detected.
• Perform Overall Function Check if DTC Confirma tion Procedure is not included on Service Manual. This
simplified check procedure is an effective alternative though DTC*
1 cannot be detected during this check.
If the result of Overall Function Check is NG, it is the same as the detection of DTC*
1 by DTC Confirmation
Procedure.
Is DTC*
1 detected?
Yes >> GO TO 10.
No >> Check according to GI-38, "
Intermittent Incident" .
6.PERFORM BASIC INSPECTION
Perform EC-13, "
Basic Inspection" .
With CONSULT-III>>GO TO 7.
Without CONSULT-III>>GO TO 9.
7.PERFORM SPEC IN DATA MONITOR MODE
With CONSULT-III
Make sure that “MAS A/F SE-B1”, “B/FUEL SCHDL”, and “A/F ALPHA-B1”, “A/F ALPHA-B2” are within the SP
value using CONSULT-III “SPEC” in “DATA MONITOR” mode. Refer to EC-74
.
Revision: April 20092010 QX56