2010 INFINITI QX56 ecm

TRANSFER CONTROL UNITDLN-99
< ECU DIAGNOSIS > [ATX14B]
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CAUTION:
• If CAN COMM CIRCUIT [U1000] or CONTROL UNIT (CAN) [U1010] is displayed with other DTCs, first perform the trouble
diagnosis for CAN communication line.
• If ABS OP SIG [P1830], VDC OP SIG [P1831] or TCS OP SIG [P 1832] is displayed, first perform the trouble diagnosis for ABS
system.
• If VHCL SPEED SEN·AT [P1807] is displayed, firs t perform the trouble diagnosis for A/T system.
NOTE:
• If SHIFT ACT POSI SW [P1818] or SHIFT ACT CIR [P1819] is disp layed, first erase self-diagnostic results. (SHIFT ACT POSI SW
[P1818] or SHIFT ACT CIR [P1819] may be displayed after installing transfer control unit or transfer assembly.)
• If CL PRES SW [P1827] or LINE PRES SW [P1828] is displayed only while driving in reverse, check the continuity of R position o n
transmission range switch. When there is no malfunction found in the electrical system, check the hydraulic system.
FLASH CODE CHART
[P1826] OIL TEMP SEN Signal voltage from transfer fluid temperature sen-
sor is abnormally high (Transfer fluid temperature is
abnormally low) while driving. Refer to
DLN-68.
[P1827] CLUTCH PRES SW • Improper signal from clutch pressure switch is in-
put due to open or short circuit.
• Malfunction occurs in clutch pressure switch or
hydraulic circuit. Refer to
DLN-71
.
[P1828] LINE PRES SW • Improper signal from line pressure switch is input
due to open or short circuit.
• Malfunction occurs in line pressure switch or hy-
draulic circuit. Refer to
DLN-74
.
[P1829] THROTTLE POSI SEN • Malfunction is detected in accelerator pedal posi-
tion signal that is output from ECM through CAN
communication.
• Signal voltage from accelerator pedal position sensor is abnormally high or low. Refer to
DLN-77
.
[P1830] ABS OP SIG Malfunction is detected in ABS operation signal that
is output from ABS actuator and electric unit (control
unit) through CAN communication. Refer to
DLN-78
.
[P1831] VDC OP SIG Malfunction is detected in VDC operation signal that
is output from ABS actuator and electric unit (control
unit) through CAN communication.
Refer to
DLN-79
.
[P1832] TCS OP SIG Malfunction is detected in TCS operation signal that
is output from ABS actuator and electric unit (control
unit) through CAN communication. Refer to
DLN-80
.
DTC CONSULT-III Diagnostic item is detected when... Reference
Flashing pattern
ItemDiagnostic item is detected when... Reference
2 Vehicle speed signal
(from A/T) • Malfunction is detected in output shaft revolution signal
that is output from TCM through CAN communication.
• Improper signal is input while driving. Refer to DLN-27
.
3 Clutch pressure sole-
noid signal Proper voltage is not applied to clutch pressure solenoid
valve due to open or short circuit.
Refer to DLN-54
.
4 2-4WD solenoid signal Proper voltage is not applied to 2-4WD solenoid valve due
to open or short circuit. Refer to DLN-58
.
5 Transfer motor Transfer motor does not operate properly due to open or
short circuit in transfer motor or transfer motor relay.
Refer to DLN-62
.
6 Vehicle speed signal
(from ABS) • Malfunction is detected in vehicle speed signal that is out-
put from ABS actuator and electric unit (control unit)
through CAN communication.
• Improper signal is input while driving. Refer to DLN-28
.
7 CAN communication Malfunction has been detected from CAN communication
line. Refer to LAN-14
.
8 AD converter AD converter system of transfer control unit is malfunction-
ing. Refer to DLN-25
.
Revision: April 20092010 QX56

DLN-100
< ECU DIAGNOSIS >[ATX14B]
TRANSFER CONTROL UNIT
9Transfer fluid tempera-
ture Signal voltage from transfer fluid temperature sensor is ab-
normally high (Transfer fluid temperature is abnormally low)
while driving.
Refer to DLN-68.
10 Neutral-4LO switch Improper signal from neutral-4LO switch is input due to
open or short circuit. Refer to DLN-29
.
11 Clutch pressure switch • Improper signal is input due to open or short circuit.
• Malfunction occurs in clutch pressure switch or hydraulic
circuit. Refer to DLN-71
.
12 Line pressure switch • Improper signal is input due to open or short circuit.
• Malfunction occurs in line pressure switch or hydraulic
circuit. Refer to DLN-74
.
13 Engine speed signal
(from ECM) • Malfunction is detected in engine speed signal that is out-
put from ECM through CAN communication.
• Improper signal is input while driving. Refer to DLN-53
.
14 Accelerator pedal posi-
tion sensor (from
ECM) • Malfunction is detected in accelerator pedal position sig-
nal that is output from ECM through CAN communication.
• Signal voltage from accelerator pedal position sensor is abnormally high or low. Refer to DLN-77
.
15 Power supply Power supply voltage for transfer control unit is abnormally
low while driving. Refer to DLN-22
.
16 4WD shift switch More than two switch inputs are simultaneously detected
due to short circuit of 4WD shift switch.
Refer to DLN-32
.
17 ABS operation signal
(from ABS) Malfunction is detected in ABS operation signal that is out-
put from ABS actuator and electric unit (control unit)
through CAN communication.
Refer to DLN-78
.
18 Wait detection switch Improper signal from wait detection switch is input due to
open or short circuit.
Refer to DLN-36
.
19 Actuator motor • Motor does not operate properly due to open or short cir-
cuit in actuator motor.
• Malfunction is detected in the actuator motor. (When
4WD shift switch is operated and actuator motor is not
operated)
• Malfunction is detected in transfer shift high relay and
transfer shift low relay. Refer to DLN-40
.
20 Actuator position
switch • Improper signal from actuator position switch is input due
to open or short circuit.
• Malfunction is detected in the actuator position switch. Refer to DLN-46
.
21 Actuator circuit • Transfer control device actuator circuit is shorted or open.
(Malfunctions are detected when motor relay circuit is
open/shorted or relay transfer shift circuit is open/short-
ed.)
• Malfunction occurs in transfer control device drive circuit. Refer to DLN-49
.
22 VDC operation signal
(from VDC) Malfunction is detected in VDC operation signal that is out-
put from ABS actuator and electric unit (control unit)
through CAN communication.
Refer to DLN-79
.
23 TCS operation signal
(from TCS) Malfunction is detected in TCS operation signal that is out-
put from ABS actuator and electric unit (control unit)
through CAN communication.
Refer to DLN-80
.
24 Transmission range
switch signal (from
TCM) When transmission range switch signal is malfunction or
communication error between the vehicles.
Refer to DLN-39
.
Repeats flickering
every 2 to 5 sec. — System normal. Refer to DLN-102
Flashing pattern
ItemDiagnostic item is detected when... Reference
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DLN-114
< SYMPTOM DIAGNOSIS >[ATX14B]
HEAVY TIGHT-CORNER BRAKING SYMPTOM OCCURS
HEAVY TIGHT-CORNER BR
AKING SYMPTOM OCCURS
DescriptionINFOID:0000000005148871
This symptom occurs when the vehicle is accelerati ng in 4WD and the steering wheel is turned fully either
direction. It may feel like a bump or being pushed fr om behind. A small amount of this bumping feeling is
acceptable under certain road conditions. The transfer case may be adjusted using the CONSULT-III to com-
pensate for this condition.
Diagnosis ProcedureINFOID:0000000005148872
DIAGNOSTIC PROCEDURE
NOTE:
• Light tight-corner braking symptom may occur depending on driving conditions in AUTO mode. This is not a malfunction.
• Heavy tight-corner braking symptom occurs when vehicle is driven in the following conditions: 4WD shift
switch is 4H or 4LO, steering wheel is turned fully to either side.
1.CHECK SYSTEM FOR CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to DLN-18, "
CONSULT-III Function (ALL MODE AWD/4WD)".
Is CAN COMM CIRCUIT [U1000] displayed?
YES >> Perform trouble diagnosis for CAN communication line.
NO >> GO TO 2.
2.CHECK SYSTEM FOR 4WD SHIFT SWITCH
Perform trouble diagnosis for 4WD shift switch system. Refer to DLN-32, "
Diagnosis Procedure".
Are the inspection results normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK ACCELERATOR PEDAL POSITION SIGNAL CIRCUIT
Perform self diagnosis for ECM. Refer to EC-63, "
CONSULT-III Function (ENGINE)".
Is any malfunction deteced by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 4.
4.CHECK SYSTEM FOR CLUT CH PRESSURE SOLENOID
Perform trouble diagnosis for clutch pressure solenoid system. Refer to DLN-71, "
Diagnosis Procedure".
Are the inspection results normal?
YES >> GO TO 5.
NO >> Repair or replace damaged parts.
5.SYMPTOM CHECK
Check again.
Are the inspection results normal?
YES >> Inspection End.
NO >> GO TO 6.
6.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-81, "
Reference Value".
Are the inspection results normal?
YES >> GO TO 7.
NO >> Check transfer control unit pin terminals fo r damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
7.CHECK TRANSFER INNER PARTS
1. Disassemble transfer assembly. Refer to DLN-142, "
Disassembly and Assembly".
2. Check transfer inner parts.
Revision: April 20092010 QX56

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-4
Component Inspection ...........................................236
P0448 EVAP CANISTER VENT CONTROL
VALVE .............................................................
238
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
Revision: April 20092010 QX56

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
Revision: April 20092010 QX56