AT-128
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)
Revision: 2007 April2007 M35/M45
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)PFP:31940
DescriptionNCS001LX
This malfunction is detected when the A/T does not shift into 5th gear position or the torque converter clutch
does not lock-up as instructed by the TCM. This is not only caused by electrical malfunction (circuits open or
shorted) but also by mechanical malfunction such as control valve sticking, improper solenoid valve operation,
etc.
CONSULT-II Reference ValueNCS001LY
On Board Diagnosis LogicNCS001LZ
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “P0744 A/T TCC S/V FNCTN” with CONSULT-II or 3rd judgement flicker without
CONSULT-II is detected under the following conditions.
–When A/T cannot perform lock-up even if electrical circuit is good.
–When TCM detects as irregular by comparing difference value with slip rotation.
Possible CauseNCS001M0
Harness or connectors
(Solenoid circuit is open or shorted.)
Torque converter clutch solenoid valve
Hydraulic control circuit
DTC Confirmation ProcedureNCS001M1
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Start engine and Select “TCC SOL FUNCTN CHECK” of “DTC
WORK SUPPORT” mode for “A/T” with CONSULT-II and touch
“START”.
2. Accelerate vehicle to more than 80 km/h (50 MPH) and maintain
the following condition continuously until “TESTING” has turned
to “COMPLETE”. (It will take approximately 30 seconds after
“TESTING” shows.)
ACCELE POSI: More than 1.0/8 (at all times during step 4)
TCC SOLENOID: 0.4 - 0.6A
SLCT LVR POSI: “D” position
[Reference speed: Constant speed of more than 80 km/h (50
MPH)]
–Make sure “GEAR” shows “5”.
–For shift schedule, refer to AT- 3 7 1 , "Vehicle Speed at Which Lock-Up Occurs/Releases" .
–If “TESTING” does not appear on CONSULT-II for a long time, select “SELF-DIAG RESULTS”. In
case a 1st trip DTC other than P0744 is shown, refer to applicable “TROUBLE DIAGNOSIS FOR
DTC”.
3. Make sure that “OK” is displayed. (If “NG” is displayed, refer to AT- 1 2 9 , "
Diagnostic Procedure" .
Refer to shift schedule, AT- 3 7 1 , "
Vehicle Speed at Which Lock-Up Occurs/Releases" .
WITH GST
Follow the procedure “WITH CONSULT-II”.
Item name Condition Display value (Approx.)
TCC SOLENOID Lock-up is active 0.4 - 0.6 A
BCIA0030E
EC-1
ENGINE CONTROL SYSTEM
B ENGINE
CONTENTS
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SECTION EC
A
EC
Revision: 2007 April2007 M35/M45
ENGINE CONTROL SYSTEM
VQ35DE
INDEX FOR DTC ...................................................... 16
DTC No. Index ....................................................... 16
Alphabetical Index .................................................. 20
PRECAUTIONS ........................................................ 24
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................ 24
Precautions for Procedures without Cowl Top Cover ... 24
On Board Diagnostic (OBD) System of Engine and
A/T .......................................................................... 24
Precaution .............................................................. 25
PREPARATION ......................................................... 28
Special Service Tools ............................................. 28
Commercial Service Tools ...................................... 29
ENGINE CONTROL SYSTEM .................................. 30
System Diagram ..................................................... 30
Multiport Fuel Injection (MFI) System .................... 31
Electronic Ignition (EI) System ............................... 33
Fuel Cut Control (At No Load and High Engine
Speed) .................................................................... 34
AIR CONDITIONING CUT CONTROL ..................... 35
Input/Output Signal Chart ....................................... 35
System Description ................................................ 35
AUTOMATIC SPEED CONTROL DEVICE (ASCD) ... 36
System Description ................................................ 36
Component Description .......................................... 37
CAN COMMUNICATION .......................................... 38
System Description ................................................ 38
EVAPORATIVE EMISSION SYSTEM ....................... 39
Description ............................................................. 39
Component Inspection ........................................... 42
Removal and Installation ........................................ 43
How to Detect Fuel Vapor Leakage ....................... 43
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ...................................................................... 46
System Description ................................................ 46
Diagnostic Procedure ............................................. 47
Component Inspection ........................................... 49POSITIVE CRANKCASE VENTILATION ................. 51
Description .............................................................. 51
Component Inspection ............................................ 51
IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-
NATS) ........................................................................ 53
Description .............................................................. 53
ON BOARD DIAGNOSTIC (OBD) SYSTEM ............ 54
Introduction ............................................................. 54
Two Trip Detection Logic ........................................ 54
Emission-Related Diagnostic Information ............... 55
Malfunction Indicator Lamp (MIL) ........................... 70
OBD System Operation Chart ................................ 73
BASIC SERVICE PROCEDURE ............................... 78
Basic Inspection ..................................................... 78
Idle Speed and Ignition Timing Check .................... 83
Procedure After Replacing ECM ............................ 85
VIN Registration ..................................................... 85
Accelerator Pedal Released Position Learning ...... 86
Throttle Valve Closed Position Learning ................. 86
Idle Air Volume Learning ........................................ 86
Fuel Pressure Check .............................................. 88
TROUBLE DIAGNOSIS ............................................ 90
Trouble Diagnosis Introduction ............................... 90
DTC Inspection Priority Chart ................................. 96
Fail-Safe Chart ....................................................... 98
Symptom Matrix Chart ............................................ 99
Engine Control Component Parts Location ..........103
Vacuum Hose Drawing ..........................................111
Circuit Diagram .....................................................112
ECM Harness Connector Terminal Layout ...........114
ECM Terminals and Reference Value ...................114
CONSULT-II Function (ENGINE) ..........................123
Generic Scan Tool (GST) Function .......................135
CONSULT-II Reference Value in Data Monitor .....138
Major Sensor Reference Graph in Data Monitor
Mode .....................................................................141
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .143
Description ............................................................143
Testing Condition ..................................................143
EC-8Revision: 2007 April2007 M35/M45 .683
Wiring Diagram .....................................................684
Diagnostic Procedure ...........................................685
Component Inspection ..........................................689
IGNITION SIGNAL ..................................................691
Component Description ........................................691
Wiring Diagram .....................................................692
Diagnostic Procedure ...........................................697
Component Inspection ..........................................702
Removal and Installation ......................................703
REFRIGERANT PRESSURE SENSOR ..................704
Component Description ........................................704
Wiring Diagram .....................................................705
Diagnostic Procedure ...........................................706
Removal and Installation ......................................708
SNOW MODE SWITCH ...........................................709
Description ............................................................709
CONSULT-II Reference Value in the Data Monitor
Mode .....................................................................709
Wiring Diagram .....................................................710
Diagnostic Procedure ...........................................711
Component Inspection ..........................................713
MIL AND DATA LINK CONNECTOR ......................714
Wiring Diagram .....................................................714
SERVICE DATA AND SPECIFICATIONS (SDS) ....716
Fuel Pressure .......................................................716
Idle Speed and Ignition Timing .............................716
Calculated Load Value ..........................................716
Mass Air Flow Sensor ...........................................716
Intake Air Temperature Sensor .............................716
Engine Coolant Temperature Sensor ...................716
Fuel Tank Temperature Sensor ............................716
Crankshaft Position Sensor (POS) .......................716
Camshaft Position Sensor (PHASE) ....................716
A/F Sensor 1 Heater .............................................716
Heated Oxygen Sensor 2 Heater .........................717
Throttle Control Motor ...........................................717
Fuel Injector ..........................................................717
Fuel Pump ............................................................717
VK45DE
INDEX FOR DTC .....................................................718
DTC No. Index ......................................................718
Alphabetical Index ................................................722
PRECAUTIONS .......................................................726
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ...............................................................726
Precautions for Procedures without Cowl Top Cover .726
On Board Diagnostic (OBD) System of Engine and
A/T ........................................................................726
Precaution ............................................................727
PREPARATION .......................................................730
Special Service Tools ...........................................730
Commercial Service Tools ....................................731
ENGINE CONTROL SYSTEM ................................732
System Diagram ...................................................732
Multiport Fuel Injection (MFI) System ...................733Electronic Ignition (EI) System ..............................735
Fuel Cut Control (At No Load and High Engine
Speed) ..................................................................736
AIR CONDITIONING CUT CONTROL ....................737
Input/Output Signal Chart .....................................737
System Description ...............................................737
AUTOMATIC SPEED CONTROL DEVICE (ASCD) .738
System Description ...............................................738
Component Description ........................................739
CAN COMMUNICATION .........................................740
System Description ...............................................740
EVAPORATIVE EMISSION SYSTEM .....................741
Description ............................................................741
Component Inspection ..........................................744
Removal and Installation .......................................745
How to Detect Fuel Vapor Leakage ......................745
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ....................................................................748
System Description ...............................................748
Diagnostic Procedure ............................................749
Component Inspection ..........................................751
POSITIVE CRANKCASE VENTILATION ................753
Description ............................................................753
Component Inspection ..........................................753
IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-
NATS) ......................................................................755
Description ............................................................755
ON BOARD DIAGNOSTIC (OBD) SYSTEM ...........756
Introduction ...........................................................756
Two Trip Detection Logic .......................................756
Emission-Related Diagnostic Information .............757
Malfunction Indicator Lamp (MIL) .........................772
OBD System Operation Chart ...............................774
BASIC SERVICE PROCEDURE .............................780
Basic Inspection ....................................................780
Idle Speed and Ignition Timing Check ..................785
Procedure After Replacing ECM ...........................787
VIN Registration ....................................................787
Accelerator Pedal Released Position Learning .....788
Throttle Valve Closed Position Learning ...............788
Idle Air Volume Learning .......................................788
Fuel Pressure Check ............................................790
TROUBLE DIAGNOSIS ..........................................792
Trouble Diagnosis Introduction .............................792
DTC Inspection Priority Chart ...............................798
Fail-Safe Chart ......................................................800
Symptom Matrix Chart ..........................................801
Engine Control Component Parts Location ...........805
Vacuum Hose Drawing .........................................814
Circuit Diagram .....................................................815
ECM Harness Connector Terminal Layout ............817
ECM Terminals and Reference Value ...................817
CONSULT-II Function (ENGINE) ..........................826
Generic Scan Tool (GST) Function .......................838
CONSULT-II Reference Value in Data Monitor .....841
Major Sensor Reference Graph in Data Monitor
Mode .....................................................................845
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .847
Description ............................................................847
PREPARATION
EC-29
[VQ35DE]
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MA
EC
Revision: 2007 April2007 M35/M45
Commercial Service ToolsNBS004S1
Tool name
(Kent-Moore No.)Description
Leak detector
i.e.: (J-41416)Locating the EVAP leak
EVAP service port
adapter
i.e.: (J-41413-OBD)Applying positive pressure through EVAP service
port
Fuel filler cap adapter
i.e.: (MLR-8382)Checking fuel tank vacuum relief valve opening
pressure
Socket wrench Removing and installing engine coolant
temperature sensor
Oxygen sensor thread
cleaner
i.e.: (J-43897-18)
(J-43897-12)Reconditioning the exhaust system threads
before installing a new oxygen sensor. Use with
anti-seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for
Zirconia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for
Titania Oxygen Sensor
Anti-seize lubricant
i.e.: (Permatex
TM
133AR or equivalent
meeting MIL
specification MIL-A-
907)Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
S-NT703
S-NT704
S-NT815
S-NT705
AEM488
S-NT779
EC-60
[VQ35DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Revision: 2007 April2007 M35/M45
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II or
GST. The 1st trip freeze frame data can only be displayed on the CONSULT-II screen, not on the GST. For
details, see EC-126, "
Freeze Frame Data and 1st Trip Freeze Frame Data" .
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM mem-
ory is erased. Procedures for clearing the ECM memory are described in EC-68, "
HOW TO ERASE EMIS-
SION-RELATED DIAGNOSTIC INFORMATION" .
SYSTEM READINESS TEST (SRT) CODE
System Readiness Test (SRT) code is specified in Service $01 of SAE J1979.
As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains
“CMPLT” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
PBIB0911E
Priority Items
1Freeze frame data Misfire — DTC: P0300 - P0306
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-61
[VQ35DE]
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EC
Revision: 2007 April2007 M35/M45
If, during the state emissions inspection, the SRT indicates “CMPLT” for all test items, the inspector will con-
tinue with the emissions test. However, if the SRT indicates “INCMP” for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If MIL is ON during the state emissions inspection, the vehicle is also returned to the customer untested even
though the SRT indicates “CMPLT” for all test items. Therefore, it is important to check SRT (“CMPLT”) and
DTC (No DTCs) before the inspection.
SRT Item
The table below shows required self-diagnostic items to set the SRT to “CMPLT”.
*: If completion of several SRTs is required, perform driving patterns (DTC confirmation procedure), one by one based on the priority for
models with CONSULT-II.
SRT Set Timing
SRT is set as “CMPLT” after self-diagnosis has been performed one or more times. Completion of SRT is
done regardless of whether the result is OK or NG. The set timing is different between OK and NG results and
is shown in the table below.
OK: Self-diagnosis is carried out and the result is OK.
NG: Self-diagnosis is carried out and the result is NG.
—: Self-diagnosis is not carried out.
When all SRT related self-diagnoses showed OK results in a single cycle (Ignition OFF-ON-OFF), the SRT will
indicate “CMPLT”. → Case 1 above
SRT item
(CONSULT-II indication)Performance
Priority*Required self-diagnostic items to set the SRT to “CMPLT”Corresponding
DTC No.
CATALYST 2 Three way catalyst function P0420, P0430
EVAP SYSTEM 2 EVAP control system purge flow monitoring P0441
1 EVAP control system P0442
2 EVAP control system P0456
HO2S 2 Air fuel ratio (A/F) sensor 1 P0133, P0153
Heated oxygen sensor 2 P0137, P0157
Heated oxygen sensor 2 P0138, P0158
Heated oxygen sensor 2 P0139, P0159
Self-diagnosis resultExample
DiagnosisIgnition cycle
← ON → OFF ← ON → OFF ← ON → OFF ← ON →
All OK Case 1 P0400 OK (1) — (1) OK (2) — (2)
P0402 OK (1) — (1) — (1) OK (2)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “CMPLT” “CMPLT” “CMPLT” “CMPLT”
Case 2 P0400 OK (1) — (1) — (1) — (1)
P0402 — (0) — (0) OK (1) — (1)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “INCMP” “INCMP” “CMPLT” “CMPLT”
NG exists Case 3 P0400 OK OK — —
P0402 — — — —
P1402 NG — NGNG
(Consecutive
NG)
(1st trip)
DTC1st trip DTC — 1st trip DTCDTC
(= MIL ON)
SRT of EGR “INCMP” “INCMP” “INCMP” “CMPLT”
PREPARATION
EC-731
[VK45DE]
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D
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K
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MA
EC
Revision: 2007 April2007 M35/M45
Commercial Service ToolsNBS0059H
Tool name
(Kent-Moore No.)Description
Leak detector
i.e.: (J-41416)Locating the EVAP leak
EVAP service port
adapter
i.e.: (J-41413-OBD)Applying positive pressure through EVAP service
port
Fuel filler cap adapter
i.e.: (MLR-8382)Checking fuel tank vacuum relief valve opening
pressure
Socket wrench Removing and installing engine coolant
temperature sensor
Oxygen sensor thread
cleaner
i.e.: (J-43897-18)
(J-43897-12)Reconditioning the exhaust system threads
before installing a new oxygen sensor. Use with
anti-seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for
Zirconia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for
Titania Oxygen Sensor
Anti-seize lubricant
i.e.: (Permatex
TM
133AR or equivalent
meeting MIL
specification MIL-A-
907)Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
S-NT703
S-NT704
S-NT815
S-NT705
AEM488
S-NT779
EC-762
[VK45DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Revision: 2007 April2007 M35/M45
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II or
GST. The 1st trip freeze frame data can only be displayed on the CONSULT-II screen, not on the GST. For
details, see EC-829, "
Freeze Frame Data and 1st Trip Freeze Frame Data" .
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM mem-
ory is erased. Procedures for clearing the ECM memory are described in EC-770, "
HOW TO ERASE EMIS-
SION-RELATED DIAGNOSTIC INFORMATION" .
SYSTEM READINESS TEST (SRT) CODE
System Readiness Test (SRT) code is specified in Service $01 of SAE J1979.
As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains
“CMPLT” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
PBIB0911E
Priority Items
1Freeze frame data Misfire — DTC: P0300 - P0308
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data