ecm INFINITI QX56 2010 Factory Workshop Manual

DLN-2
P1820 ENGINE SPEED SIGNAL ......................53
Description ........................................................... ...53
DTC Logic ...............................................................53
Diagnosis Procedure ..............................................53
P1822 CLUTCH PRESSURE SOLENOID .........54
Description ..............................................................54
DTC Logic ...............................................................54
Diagnosis Procedure ..............................................54
Component Inspection ............................................57
P1823 2-4 SOLENOID .......................................58
Description ........................................................... ...58
DTC Logic ...............................................................58
Diagnosis Procedure ..............................................58
Component Inspection ............................................61
P1824 TRANSFER MOTOR ..............................62
Description ..............................................................62
DTC Logic ...............................................................62
Diagnosis Procedure ..............................................62
Component Inspection ............................................66
P1826 TRANSFER FLUID TEMPERATURE ....68
Description ........................................................... ...68
DTC Logic ...............................................................68
Diagnosis Procedure ..............................................68
Component Inspection ............................................69
P1827 CLUTCH PRESSURE SWITCH .............71
Description ........................................................... ...71
DTC Logic ...............................................................71
Diagnosis Procedure ..............................................71
Component Inspection ............................................73
P1828 LINE PRESSURE SWITCH ....................74
Description ........................................................... ...74
DTC Logic ...............................................................74
Diagnosis Procedure ..............................................74
Component Inspection ............................................76
P1829 THROTTLE POSITION SIGNAL (ECM)
...
77
Description ........................................................... ...77
DTC Logic ...............................................................77
Diagnosis Procedure ..............................................77
P1830 ABS OPERATION SIGNAL (ABS) ........78
Description ........................................................... ...78
DTC Logic ...............................................................78
Diagnosis Procedure ..............................................78
P1831 VDC OPERATION SIGNAL (ABS) ........79
Description ........................................................... ...79
DTC Logic ...............................................................79
Diagnosis Procedure ..............................................79
P1832 TCS OPERATION SIGNAL (ABS) .........80
Description ........................................................... ...80
DTC Logic ...............................................................80
Diagnosis Procedure ..............................................80
ECU DIAGNOSIS .......................................81
TRANSFER CONTROL UNIT ...........................81
Reference Value .................................................. ...81
Wiring Diagram - ALL-MODE 4WD SYSTEM - .... ...89
DTC Index ............................................................ ...97
SYMPTOM DIAGNOSIS ...........................102
4WD SYSTEM SYMPTOMS ........................... ..102
Symptom Table .................................................... .102
4WD SHIFT INDICATOR LAMP AND 4LO IN-
DICATOR LAMP DO NOT TURN ON ..............
103
Description ............................................................103
Diagnosis Procedure .............................................103
4WD WARNING LAMP DOES NOT TURN ON ..105
Description ........................................................... .105
Diagnosis Procedure .............................................105
4WD SHIFT INDICATOR LAMP OR 4LO INDI-
CATOR LAMP DO NOT CHANGE ...................
107
Description ........................................................... .107
Diagnosis Procedure .............................................107
ATP WARNING LAMP DOES NOT TURN ON ..109
Description ........................................................... .109
Diagnosis Procedure .............................................109
4WD SHIFT INDICATOR LAMP KEEPS
FLASHING ........................................................
111
Description ........................................................... .111
Diagnosis Procedure .............................................111
4WD WARNING LAMP FLASHES RAPIDLY ..112
Description ............................................................112
Diagnosis Procedure .............................................112
4WD WARNING LAMP FLASHES SLOWLY ..113
Description ............................................................113
Diagnosis Procedure .............................................113
HEAVY TIGHT-CORNER BRAKING SYMP-
TOM OCCURS ................................................ ..
114
Description ........................................................... .114
Diagnosis Procedure .............................................114
ATP SWITCH ....................................................116
Description ........................................................... .116
Diagnosis Procedure .............................................116
4WD SYSTEM DOES NOT OPERATE ............118
Description ........................................................... .118
Diagnosis Procedure .............................................118
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING ...........................
119
NVH Troubleshooting Chart ..................................119
PRECAUTION ............... ............................120
Revision: April 20092010 QX56

4WD SYSTEMDLN-11
< FUNCTION DIAGNOSIS > [ATX14B]
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CONTROL SYSTEM
ABS actuator and electric unit
(control unit) Transmits vehicle speed signal via CAN communication to transfer control unit.
TCM Transmits the following signal via CAN communication to transfer control unit.
• Output shaft revolution signal
• A/T position indicator signal (transmission range switch signal)
ECM Transmits the following signals via CAN communication to transfer control unit.
• Engine speed signal
• Accelerator pedal position signal
Components
Function
Revision: April 20092010 QX56

DIAGNOSIS SYSTEM (TRANSFER CONTROL UNIT)DLN-19
< FUNCTION DIAGNOSIS > [ATX14B]
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12. Move A/T selector lever to N position.
13. Turn 4WD shift switch to AUTO position.
14. Move A/T selector lever to P position.
15. Read the flickering of 4WD warning lamp.
Self-diagnosis example
ERASE SELF-DIAGNOSIS
• In order to make it easier to find the cause of hard-to-duplicate malfunctions, malfunction information is
stored into the control unit as necessary during use by the user. This memory is not erased no matter how
many times the ignition switch is turned ON and OFF.
• However, this information is erased by turning igni tion switch OFF after performing self-diagnostics or by
erasing the memory using the CONSULT-III.
DATA MONITOR MODE
Operation Procedure
1. Connect CONSULT-III.
2. Touch DATA MONITOR.
3. Select from SELECT MONITOR ITEM, screen of data monitor mode is displayed.
NOTE:
When malfunction is detected, CONSUL T-III performs REAL-TIME DIAGNOSIS.
Also, any malfunction detected while in th is mode will be displayed at real time.
Display Item List
×: Standard –: Not applicable
PDIA0227E
Monitored item (Unit) Monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELEC-
TION FROM MENU
VHCL/S SEN·FR [km/h] or [mph] ×–×Wheel speed calculated by ABS actuator and
electric unit (control unit).
Signal input with CAN communication line.
VHCL/S SEN·RR [km/h] or [mph] ×–×Wheel speed calculated by TCM.
Signal input with CAN communication line.
ENGINE SPEED [rpm] ×–×Engine speed calculated by ECM.
Signal input with CAN communication line.
THRTL POS SEN [V] ×–×Accelerator peda
l position (APP) sensor sig-
nal voltage is displayed.
Signal input with CAN communication line.
FLUID TEMP SE [V] ×–×Transfer fluid temperature sensor signal volt-
age is displayed.
BATTERY VOLT [V] ×–×Power supply voltage for transfer control unit.
2WD SWITCH [On/Off] ×–×4WD shift switch status is displayed.
AUTO SWITCH [On/Off] ×–×4WD shift switch status is displayed.
LOCK SWITCH [On/Off] ×–×4WD shift switch status is displayed.
(LOCK means 4H of 4WD shift switch.)
Revision: April 20092010 QX56

P1820 ENGINE SPEED SIGNALDLN-53
< COMPONENT DIAGNOSIS > [ATX14B]
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P1820 ENGINE SPEED SIGNAL
DescriptionINFOID:0000000005148814
The ECM transmits the engine speed signal via CAN comm unication to the transfer control unit. DTC P1820
will set when either of the following occur:
• Malfunction is detected in engine speed signal that is output from the ECM.
• Improper signal is input while driving.
DTC LogicINFOID:0000000005148815
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1820 detected?
YES >> Perform diagnosis procedure. Refer to DLN-53, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000005148816
1.CHECK DTC WITH ECM
Perform self-diagnosis with ECM. Refer to EC-63, "
CONSULT-III Function (ENGINE)".
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.
2.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 3.
NO >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
3.CHECK DTC
Drive the vehicle and then perform self-diagnosis.
Are the inspection results normal?
YES >> Inspection End.
NO >> Perform self-diagnosis with ECM again.
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1820] ENGINE SPEED SIG • Malfunction is detected in engine
speed signal that is output from ECM
through CAN communication.
• Improper signal is input while driving. Refer to DLN-53
.
Revision: April 20092010 QX56

P1829 THROTTLE POSITION SIGNAL (ECM)
DLN-77
< COMPONENT DIAGNOSIS > [ATX14B]
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P1829 THROTTLE POSITION SIGNAL (ECM)
DescriptionINFOID:0000000005148841
Malfunction is detected in accelerator pedal position si gnal that is output from ECM through CAN communica-
tion. Also, the signal voltage from accelerator pedal position sensor may be abnormally high or low.
DTC LogicINFOID:0000000005148842
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1829 displayed?
YES >> Perform diagnosis procedure. Refer to DLN-77, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000005148843
1.CHECK DTC WITH ECM
Perform self-diagnosis with ECM. Refer to EC-63, "
CONSULT-III Function (ENGINE)".
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.
2.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-81, "
Reference Value".
Are inspection results normal?
YES >> GO TO 3.
NO >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
3.CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
Are inspection results normal?
YES >> Inspection End.
NO >> Perform self-diagnosis with ECM again.
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1829] THROTTLE POSI SEN • Malfunction is detected in accelerator
pedal position signal that is output
from ECM through CAN communica-
tion.
• Signal voltage from accelerator pedal position sensor is abnormally high or
low. Refer to DLN-77
.
Revision: April 20092010 QX56

DLN-98
< ECU DIAGNOSIS >[ATX14B]
TRANSFER CONTROL UNIT
DTC CONSULT-III
Diagnostic item is detected when... Reference
[P1802] CONTROL UNIT 1 Malfunction is detected in the memory (RAM) sys-
tem of transfer control unit.
Refer to DLN-25
.
[P1803] CONTROL UNIT 2 Malfunction is detected in the memory (ROM) sys-
tem of transfer control unit.
[P1804] CONTROL UNIT 3 Malfunction is detected
in the memory (EEPROM)
system of transfer control unit.
[P1807] VHCL SPEED SEN·AT • Malfunction is detected in output shaft revolution
signal that is output from TCM through CAN com-
munication.
• Improper signal is input while driving. Refer to DLN-27
.
[P1808] VHCL SPEED SEN·ABS • Malfunction is detected in vehicle speed signal
that is output from ABS actuator and electric unit
(control unit) through CAN communication.
• Improper signal is input while driving. Refer to DLN-28
.
[P1809] CONTROL UNIT 4 AD converter system of transfer control unit is mal-
functioning. Refer to DLN-25
.
[P1810] 4L POSI SW TF Improper signal from neutral-4LO switch is input due
to open or short circuit. Refer to DLN-29
.
[ P 1 8 11 ] B AT T E R Y V O LTA G E Power supply voltage for transfer control unit is ab-
normally low while driving.
Refer to DLN-22
.
[P1813] 4WD MODE SW More than two switch inputs are simultaneously de-
tected due to short circuit of 4WD shift switch. Refer to DLN-32
.
[P1814] 4WD DETECT SWITCH Improper signal from wait detection switch is input
due to open or short circuit. Refer to DLN-36
.
[P1816] PNP SW/CIRC When transmission range switch signal is malfunc-
tion or communication error between the control
units. Refer to DLN-39
.
[P1817] SHIFT ACTUATOR • Motor does not operate properly due to open or
short circuit 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
.
[P1818] SHIFT ACT POSI SW • Improper signal from actuator position switch is in-
put due to open or short circuit.
• Malfunction is detected in the actuator position
switch. Refer to DLN-46
.
[P1819] SHIFT ACT CIR • Transfer control device actuator circuit is shorted
or open. (Malfunctions are detected when transfer
shift relay circuit is open/shorted or relay monitor
circuit is open/shorted.)
• Malfunction occurs in transfer control device drive circuit.
• Malfunction is detected in transfer shut off relay. Refer to DLN-49
.
[P1820] ENGINE SPEED SIG • Malfunction is detected in engine speed signal
that is output from ECM through CAN communi-
cation.
• Improper signal is input while driving. Refer to DLN-53
.
[P1822] DUTY SOLENOID Proper voltage is not applied to clutch pressure so-
lenoid valve due to open or short circuit. Refer to DLN-54
.
[P1823] 2-4WD SOLENOID Proper voltage is not applied to 2-4WD solenoid
valve due to open or short circuit. Refer to DLN-58
.
[P1824] MOTOR RELAY Motor does not operate properly due to open or
short circuit in transfer motor or transfer motor relay.
Refer to DLN-62
.
Revision: April 20092010 QX56

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
Revision: April 20092010 QX56

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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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
Revision: April 20092010 QX56