2001 INFINITI QX4 engine mechanical

SAT964I
Malfunction Indicator Lamp (MIL)=NBAT0183The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned ON
without the engine running. This is a bulb check.
IIf the MIL does not light up, refer to EL-114, ªSchematicº.
(Or refer to EC-648, ªWiring Diagramº.)
2. When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction. For detail, refer to
EC-59, ªIntroductionº.
CONSULT-IINBAT0184After performing ªSELF-DIAGNOSTIC PROCEDURE (WITH CON-
SULT-II)º (AT-37), place check marks for results on the ªDIAGNOS-
TIC WORKSHEETº, AT-55. Reference pages are provided follow-
ing the items.
NOTICE:
1) The CONSULT-II electrically displays shift timing and lock-up
timing (that is, operation timing of each solenoid).
Check for time difference between actual shift timing and the
CONSULT-II display. If the difference is noticeable, mechani-
cal parts (except solenoids, sensors, etc.) may be malfunction-
ing. Check mechanical parts using applicable diagnostic pro-
cedures.
2) Shift schedule (which implies gear position) displayed on
CONSULT-II and that indicated in Service Manual may differ
slightly. This occurs because of the following reasons:
IActual shift schedule has more or less tolerance or allowance,
IShift schedule indicated in Service Manual refers to the point
where shifts start, and
IGear position displayed on CONSULT-II indicates the point
where shifts are completed.
3) Shift solenoid valve ªAº or ªBº is displayed on CONSULT-II at
the start of shifting. Gear position is displayed upon completion
of shifting (which is computed by TCM).
4) Additional CONSULT-II information can be found in the Opera-
tion Manual supplied with the CONSULT-II unit.
SAT014K
SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)NBAT0184S011. Turn on CONSULT-II and touch ªENGINEº for OBD-II detected
items or touch ªA/Tº for TCM self-diagnosis.
If A/T is not displayed, check TCM power supply and ground
circuit. Refer to AT-92. If result is NG, refer to EL-9, ªSche-
maticº.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Malfunction Indicator Lamp (MIL)
AT-37

DescriptionNBAT0039IThis is an OBD-II self-diagnostic item and not available in TCM
self-diagnosis.
IThis malfunction will not be detected while the O/D OFF indi-
cator lamp is indicating another self-diagnosis malfunction.
IThis malfunction is detected when the A/T does not shift into
first gear position as instructed by the TCM. This is not caused
by electrical malfunction (circuits open or shorted) but by
mechanical malfunction such as control valve sticking,
improper solenoid valve operation, etc.
Gear position1234
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
TCM TERMINALS AND REFERENCE VALUENBAT0039S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
11 L/WShift solenoid
valve A
When shift solenoid valve A operates.
(When driving in ªD
1ºorªD4º.)Battery volt-
age
When shift solenoid valve A does not operate.
(When driving in ªD
2ºorªD3º.)0V
12 L/RShift solenoid
valve BWhen shift solenoid valve B operates.
(When driving in ªD
1ºorªD2º.)Battery volt-
age
When shift solenoid valve B does not operate.
(When driving in ªD
3ºorªD4º.)0V
ON BOARD DIAGNOSIS LOGICNBAT0039S03This diagnosis monitors actual gear position by checking the torque
converter slip ratio calculated by TCM as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is higher than the position (1st) supposed
by TCM, the slip ratio will be more than normal. In case the ratio
exceeds the specified value, TCM judges this diagnosis malfunc-
tion.
This malfunction will be caused when either shift solenoid valve A
is stuck open or shift solenoid valve B is stuck open.
Gear position supposed by TCM1234
In case of gear position with no malfunctions1234
In case of gear position with shift solenoid valve A stuck open 2* 2 3 3
In case of gear position with shift solenoid valve B stuck open 4* 3 3 4
*: P0731 is detected.
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: A/T 1ST GR FNCTN
A/T cannot be shifted to the 1st gear
position even if electrical circuit is good.IShift solenoid valve A
IShift solenoid valve B
IEach clutch
IHydraulic control circuit
: P0731
DTC P0731 IMPROPER SHIFTING TO 1ST GEAR POSITION
Description
AT-120

DescriptionNBAT0042IThis is an OBD-II self-diagnostic item and not available in TCM
self-diagnosis.
IThis malfunction will not be detected while the O/D OFF indi-
cator lamp is indicating another self-diagnosis malfunction.
IThis malfunction is detected when the A/T does not shift into
second gear position as instructed by the TCM. This is not
caused by electrical malfunction (circuits open or shorted) but
by mechanical malfunction such as control valve sticking,
improper solenoid valve operation, etc.
Gear position1234
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
TCM TERMINALS AND REFERENCE VALUENBAT0042S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
12 L/RShift solenoid
valve B
When shift solenoid valve B operates.
(When driving in ªD
1ºorªD2º.)Battery volt-
age
When shift solenoid valve B does not operate.
(When driving in ªD
3ºorªD4º.)0V
ON BOARD DIAGNOSIS LOGICNBAT0042S03This diagnosis monitors actual gear position by checking the torque
converter slip ratio calculated by TCM as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is higher than the position (2nd) sup-
posed by TCM, the slip ratio will be more than normal. In case the
ratio exceeds the specified value, TCM judges this diagnosis mal-
function.
This malfunction will be caused when shift solenoid valve B is stuck
open.
Gear position supposed by TCM 1 2 3 4
In case of gear position with no malfunctions 1 2 3 4
In case of gear position with shift solenoid valve B
stuck open43* 3 4
*: P0732 is detected.
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: A/T 2ND GR FNCTN
A/T cannot be shifted to the 2nd gear
position even if electrical circuit is good.IShift solenoid valve B
IEach clutch
IHydraulic control circuit
: P0732
DTC P0732 IMPROPER SHIFTING TO 2ND GEAR POSITION
Description
AT-126

DescriptionNBAT0045IThis is an OBD-II self-diagnostic item and not available in TCM
self-diagnosis.
IThis malfunction will not be detected while the O/D OFF indi-
cator lamp is indicating another self-diagnosis malfunction.
IThis malfunction is detected when the A/T does not shift into
third gear position as instructed by the TCM. This is not caused
by electrical malfunction (circuits open or shorted) but by
mechanical malfunction such as control valve sticking,
improper solenoid valve operation, malfunctioning servo piston
or brake band, etc.
Gear position1234
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
TCM TERMINALS AND REFERENCE VALUENBAT0045S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
11 L/WShift solenoid
valve A
When shift solenoid valve A operates.
(When driving in ªD
1ºorªD4º.)Battery volt-
age
When shift solenoid valve A does not operate.
(When driving in ªD
2ºorªD3º.)0V
ON BOARD DIAGNOSIS LOGICNBAT0045S03This diagnosis monitors actual gear position by checking the torque
converter slip ratio calculated by TCM as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is higher than the position (3rd) supposed
by TCM, the slip ratio will be more than normal. In case the ratio
exceeds the specified value, TCM judges this diagnosis malfunc-
tion.
This malfunction will be caused when shift solenoid valve A is stuck
closed.
Gear position supposed by TCM1234
In case of gear position with no malfunctions1234
In case of gear position with shift solenoid valve A
stuck closed1 1 4* 4
*: P0733 is detected.
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: A/T 3RD GR FNCTN
A/T cannot be shifted to the 3rd gear
position even if electrical circuit is good.IShift solenoid valve A
IEach clutch
IHydraulic control circuit
: P0733
DTC P0733 IMPROPER SHIFTING TO 3RD GEAR POSITION
Description
AT-132

DescriptionNBAT0048IThis is an OBD-II self-diagnostic item and not available in TCM
self-diagnosis.
IThis malfunction will not be detected while the O/D OFF indi-
cator lamp is indicating another self-diagnosis malfunction.
IThis malfunction is detected when the A/T does not shift into
fourth gear position or the torque converter clutch does not
lock up as instructed by the TCM. This is not caused by elec-
trical malfunction (circuits open or shorted) but by mechanical
malfunction such as control valve sticking, improper solenoid
valve operation, malfunctioning oil pump or torque converter
clutch, etc.
CONSULT-II REFERENCE VALUE IN DATA MONITOR
MODE
NBAT0048S04Remarks: Specification data are reference values.
Monitor item Condition Specification
Line pressure solenoid valve
dutySmall throttle opening (Low line pressure)
"
Large throttle opening (High line pressure)Approximately 24%
"
Approximately 95%
Gear position1234
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
TCM TERMINALS AND REFERENCE VALUENBAT0048S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
1GYLine pressure
solenoid valve
When releasing accelerator pedal after warm-
ing up engine.1.5 - 3.0V
When depressing accelerator pedal fully after
warming up engine.0V
2 BR/YLine pressure
solenoid valve
(with dropping
resistor)When releasing accelerator pedal after warm-
ing up engine.5 - 14V
When depressing accelerator pedal fully after
warming up engine.0V
11 L/WShift solenoid
valve A
When shift solenoid valve A operates.
(When driving in ªD
1ºorªD4º.)Battery volt-
age
When shift solenoid valve A does not operate.
(When driving in ªD
2ºorªD3º.)0V
12 L/RShift solenoid
valve BWhen shift solenoid valve B operates.
(When driving in ªD
1ºorªD2º.)Battery volt-
age
When shift solenoid valve B does not operate.
(When driving in ªD
3ºorªD4º.)0V
DTC P0734 IMPROPER SHIFTING TO 4TH GEAR POSITION
Description
AT-138

DescriptionNBAT0054IThis is an OBD-II self-diagnostic item and not available in TCM
self-diagnosis.
IThis malfunction will not be detected while the O/D OFF indi-
cator lamp is indicating another self-diagnosis malfunction.
IThis malfunction is detected when the A/T does not shift into
fourth gear position or the torque converter clutch does not
lock up as instructed by the TCM. This is not caused by elec-
trical malfunction (circuits open or shorted) but by mechanical
malfunction such as control valve sticking, improper solenoid
valve operation, malfunctioning oil pump or torque converter
clutch, etc.
CONSULT-II REFERENCE VALUE IN DATA MONITOR
MODE
NBAT0054S02Remarks: Specification data are reference values.
Monitor item Condition Specification
Torque converter clutch
solenoid valve dutyLock-up ªOFFº
"
Lock-up ªONºApproximately 4%
"
Approximately 94%
Line pressure solenoid
valve dutySmall throttle opening (Low line pressure)
"
Large throttle opening (High line pressure)Approximately 24%
"
Approximately 95%
TCM TERMINALS AND REFERENCE VALUENBAT0054S03Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
1GYLine pressure
solenoid valve
When releasing accelerator pedal after warm-
ing up engine.1.5 - 3.0V
When depressing accelerator pedal fully after
warming up engine.0V
2 BR/YLine pressure
solenoid valve
(with dropping
resistor)When releasing accelerator pedal after warm-
ing up engine.5 - 14V
When depressing accelerator pedal fully after
warming up engine.0V
3 G/ORTorque converter
clutch solenoid
valve
When A/T performs lock-up. 8 - 15V
When A/T does not perform lock- up. 0V
ON BOARD DIAGNOSIS LOGICNBAT0054S04This diagnosis monitors actual gear position by checking the torque
converter slip ratio calculated by TCM as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is much lower than the position (4th)
supposed by TCM, the slip ratio will be much less than normal. In
case the ratio does not reach the specified value, TCM judges this
diagnosis malfunction.
This malfunction will be caused when shift solenoid valve B is stuck
closed.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0744 IMPROPER LOCK-UP OPERATION
Description
AT-153

PurposeNBBR0087The Anti-Lock Brake System (ABS) consists of electronic and hydraulic components. It allows for control of
braking force so locking of the wheels can be avoided.
1) Improves proper tracking performance through steering wheel operation.
2) Eases obstacle avoidance through steering wheel operation.
3) Improves vehicle stability.
OperationNBBR0088IWhen the vehicle speed is less than 10 km/h (6 MPH) this system does not work.
IThe Anti-Lock Brake System (ABS) has a self-test function. The system turns on the ABS warning lamp
for 1 second each time the ignition switch is turned ªONº. After the engine is started, the ABS warning lamp
turns off. The system performs a test the first time the vehicle reaches 6 km/h (4 MPH). A mechanical noise
may be heard as the ABS performs this self-test. This is a normal part of the self-test feature. If a mal-
function is found during this check, the ABS warning lamp will stay on.
IWhile driving, a mechanical noise may be heard during ABS operation. This is a normal condition.
ABS Hydraulic CircuitNBBR0089
SBR859D
1. Inlet solenoid valve
2. Outlet solenoid valve
3. Reservoir4. Pump
5. Motor
6. Inlet valve7. Outlet valve
8. Bypass check valve
9. Damper
DESCRIPTIONABS
Purpose
BR-32

Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
INT/A TEMP SE
[ÉC] or [ÉF]qqIThe intake air temperature determined
by the signal voltage of the intake air
temperature sensor is indicated.
EVAP SYS PRES [V]qIThe signal voltage of EVAP control sys-
tem pressure sensor is displayed.
ABSOL PRES/SE [V]qIThe signal voltage of the absolute pres-
sure sensor is displayed.
FUEL LEVEL SE [V]qIThe signal voltage of the fuel level sen-
sor is displayed.
START SIGNAL
[ON/OFF]qqIIndicates [ON/OFF] condition from the
starter signal.IAfter starting the engine, [OFF] is dis-
played regardless of the starter signal.
CLSD THL POS
[ON/OFF]qqIIndicates idle position [ON/OFF] com-
puted by ECM according to the throttle
position sensor signal.
CLSD THL/P SW
[ON/OFF]qIIndicates mechanical contact [ON/OFF]
condition of the closed throttle position
switch.
AIR COND SIG
[ON/OFF]qqIIndicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
P/N POSI SW
[ON/OFF]qqIIndicates [ON/OFF] condition from the
park/neutral position (PNP) switch sig-
nal.
PW/ST SIGNAL
[ON/OFF]qqI[ON/OFF] condition of the power steer-
ing oil pressure switch determined by
the power steering oil pressure signal is
indicated.
LOAD SIGNAL
[ON/OFF]qqIIndicates [ON/OFF] condition from the
electrical load signal and/or lighting
switch.
ON ... rear defogger is operating and/or
lighting switch is on.
OFF ... rear defogger is not operating
and lighting switch is not on.
IGNITION SW
[ON/OFF]qIIndicates [ON/OFF] condition from igni-
tion switch.
SWRL CONT S/V
[ON/OFF]qIThe control condition of the swirl con-
trol valve control solenoid valve (deter-
mined by ECM according to the input
signals) is indicated.
ION ... Swirl control valve is closed.
OFF ... Swirl control valve is opened.
INJ PULSE-B1
[msec]q
IIndicates the actual fuel injection pulse
width compensated by ECM according
to the input signals.IWhen the engine is stopped, a certain
computed value is indicated.
INJ PULSE-B2
[msec]
B/FUEL SCHDL
[msec]qIªBase fuel scheduleº indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board
correction.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
CONSULT-II (Cont'd)
EC-88