check engine INFINITI QX4 2005 Factory User Guide

A/T CONTROL SYSTEM
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TCM FunctionECS00CDW
The function of the TCM is to:

Receive input signals sent from various switches and sensors.

Determine required line pressure, shifting point, lock-up operation, and engine brake operation.

Send required output signals to the respective solenoids.
CONTROL SYSTEM OUTLINE
The automatic transmission senses vehicle operating conditions through various sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
CONTROL SYSTEM DIAGRAM
SENSORS (or SIGNALS)


TCM


ACTUATORS
PNP switch
Accelerator pedal position sensor
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Vehicle speed signal
Stop lamp switch signal
Turbine revolution sensor
1st position switch signal
4th position switch signal
ATF pressure switch signal
Tow mode switch signalShift control
Line pressure control
Lock-up control
Engine brake control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
Duet-EA control
CAN systemInput clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch
solenoid valve
Low coast brake solenoid valve
Torque converter clutch solenoid
valve
Line pressure solenoid valve
A/T CHECK indicator lamp
Sta rte r re lay
Back-up lamp relay
SCIA5624E

ON BOARD DIAGNOSTIC (OBD) SYSTEM
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ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
IntroductionECS00CE4
The A/T system has two self-diagnostic systems.
The first is the emission-related on board diagnostic system (OBD-II) performed by the TCM in combination
with the ECM. The malfunction is indicated by the MIL (malfunction indicator lamp) and is stored as a DTC in
the ECM memory but not the TCM memory.
The second is the TCM original self-diagnosis indicated by the A/T CHECK indicator lamp. The malfunction is
stored in the TCM memory. The detected items are overlapped with OBD-II self-diagnostic items. For detail,
refer to AT- 8 5 , "
SELF-DIAGNOSTIC RESULT MODE" .
OBD-II Function for A/T SystemECS00CE5
The ECM provides emission-related on board diagnostic (OBD-II) functions for the A/T system. One function
is to receive a signal from the TCM used with OBD-related parts of the A/T system. The signal is sent to the
ECM when a malfunction occurs in the corresponding OBD-related part. The other function is to indicate a
diagnostic result by means of the MIL (malfunction indicator lamp) on the instrument panel. Sensors, switches
and solenoid valves are used as sensing elements.
The MIL automatically illuminates in One or Two Trip Detection Logic when a malfunction is sensed in relation
to A/T system parts.
One or Two Trip Detection Logic of OBD-IIECS00CE6
ONE TRIP DETECTION LOGIC
If a malfunction is sensed during the first test drive, the MIL will illuminate and the malfunction will be stored in
the ECM memory as a DTC. The TCM is not provided with such a memory function.
TWO TRIP DETECTION LOGIC
When a malfunction is sensed during the first test drive, it is stored in the ECM memory as a 1st trip DTC
(diagnostic trouble code) or 1st trip freeze frame data. At this point, the MIL will not illuminate. — 1st Trip
If the same malfunction as that experienced during the first test drive is sensed during the second test drive,
the MIL will illuminate. — 2nd Trip
The “Trip” in the “One or Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation.
OBD-II Diagnostic Trouble Code (DTC)ECS00CE7
HOW TO READ DTC AND 1ST TRIP DTC
DTC and 1st trip DTC can be read by the following methods.
( with CONSULT-II or GST) CONSULT-II or GST (Generic Scan Tool) Examples: P0705, P0720 etc.
These DTC are prescribed by SAE J2012.
(CONSULT-II also displays the malfunctioning component or system.)

1st trip DTC No. is the same as DTC No.

Output of the diagnostic trouble code indicates that the indicated circuit has a malfunction. How-
ever, in case of the Mode II and GST, they do not indicate whether the malfunction is still occurring
or occurred in the past and returned to normal.
CONSULT-II can identify them as shown below, therefore, CONSULT-II (if available) is recom-
mended.
A sample of CONSULT-II display for DTC and 1st trip DTC is shown
on the next page. DTC or 1st trip DTC of a malfunction is displayed
in SELF-DIAGNOSTIC RESULTS mode for “ENGINE” with CON-
SULT-II. Time data indicates how many times the vehicle was driven
after the last detection of a DTC.
BCIA0030E

AT-40
ON BOARD DIAGNOSTIC (OBD) SYSTEM
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Malfunction Indicator Lamp (MIL)ECS00CE8
DESCRIPTION
The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned “ON” with-
out the engine running. This is a bulb check.

If the MIL does not light up, refer to DI-30, "WARNING LAMPS" .
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.
SEF 2 17 U

TROUBLE DIAGNOSIS
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How To Perform Trouble Diagnosis For Quick and Accurate RepairECS00CEB
INTRODUCTION
The TCM receives a signal from the vehicle speed sensor, accelerator pedal position sensor (throttle position
sensor) or PNP switch and provides shift control or lock-up control via A/T solenoid valves.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used with the OBD-related parts of the
A/T system for malfunction-diagnostic purposes. The TCM is capa-
ble of diagnosing malfunctioning parts while the ECM can store mal-
functions in its memory.
Input and output signals must always be correct and stable in the
operation of the A/T system. The A/T system must be in good oper-
ating condition and be free of valve seizure, solenoid valve malfunc-
tion, etc.
It is much more difficult to diagnose a error that occurs intermittently
rather than continuously. Most intermittent errors are caused by poor
electric connections or improper wiring. In this case, careful check-
ing of suspected circuits may help prevent the replacement of good
parts.
A visual check only may not find the cause of the errors. A road test
with CONSULT-II (or GST) or a circuit tester connected should be
performed. Follow the AT-44, "
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 errors, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “Diagnostic Worksheet” as shown on
the example (Refer to AT- 4 5
) should be used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot driveability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
SAT6 3 1IB
SAT6 3 2I
SEF 2 34 G

AT-46
TROUBLE DIAGNOSIS
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4❏ Perform all road tests and enter checks in required inspection items.AT-5 3
4-1.Check before engine is started
AT-5 4
❏ AT-180, "A/T CHECK Indicator Lamp Does Not Come On" .
❏ Perform self-diagnostics Enter checks for detected items. AT- 8 5
❏ AT- 9 5 , "DTC U1000 CAN COMMUNICATION LINE"
❏ AT- 9 9 , "DTC P0615 START SIGNAL CIRCUIT"
❏ AT- 1 0 3 , "DTC P0700 TCM"
❏ AT- 1 0 4 , "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT- 1 0 8 , "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT- 11 3 , "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT- 11 5 , "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT- 11 7 , "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT- 11 9 , "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT- 1 2 1 , "DTC P1702 TRANSMISSION CONTROL MODULE (RAM)"
❏ AT- 1 2 2 , "DTC P1703 TRANSMISSION CONTROL MODULE (ROM)"
❏ AT- 1 2 3 , "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT- 1 2 6 , "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT- 1 3 1 , "DTC P1716 TURBINE REVOLUTION SENSOR"
❏ AT- 1 3 3 , "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT- 1 3 5 , "DTC P1730 A/T INTERLOCK"
❏ AT- 1 3 8 , "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT- 1 4 0 , "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT- 1 4 2 , "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT- 1 4 4 , "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT- 1 4 6 , "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT- 1 4 8 , "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT- 1 5 0 , "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT- 1 5 2 , "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT- 1 5 4 , "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT- 1 5 6 , "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT- 1 5 8 , "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT- 1 6 0 , "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT- 1 6 2 , "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT- 1 6 4 , "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT- 1 6 6 , "DTC P1846 ATF PRESSURE SWITCH 6"
4-2.Idle inspection
AT-5 4
❏ AT-180, "Engine Cannot Be Started In “P” or “N” Position"
❏ AT-181, "In “P” Position, Vehicle Moves When Pushed"
❏ AT-182, "In “N” Position, Vehicle Moves"
❏ AT-183, "Large Shock (“N” to “D” Position)"
❏ AT-187, "Vehicle Does Not Creep Backward In “R” Position"
❏ AT-190, "Vehicle Does Not Creep Forward In “D” Position"
4-3.Driving tests
AT-5 5
Part 1
❏ AT-192, "
Vehicle Cannot Be Started From D1"
❏ AT-195, "A/T Does Not Shift: D1 → D2"
❏ AT-197, "A/T Does Not Shift: D2 → D3"
❏ AT-199, "A/T Does Not Shift: D3 → D4"
❏ AT-202, "A/T Does Not Shift: D4 → D5"
❏ AT-204, "A/T Does Not Perform Lock-up"
❏ AT-206, "A/T Does Not Hold Lock-up Condition"
❏ AT-208, "Lock-up Is Not Released"
❏ AT-209, "Engine Speed Does Not Return to Idle"

TROUBLE DIAGNOSIS
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44-3Part 2
AT- 5 7
❏ AT-192, "Vehicle Cannot Be Started From D1"
❏ AT-195, "A/T Does Not Shift: D1 → D2"
❏ AT-197, "A/T Does Not Shift: D2 → D3"
❏ AT-199, "A/T Does Not Shift: D3 → D4"
Part 3
AT- 5 8
❏ AT-210, "A/T Does Not Shift: 5th gear → 4th gear"
❏ AT-213, "A/T Does Not Shift: 4th gear → 3rd gear"
❏ AT-214, "A/T Does Not Shift: 3rd gear → 2nd gear"
❏ AT-216, "A/T Does Not Shift: 2nd gear → 1st gear"
❏ AT-219, "Vehicle Does Not Decelerate By Engine Brake"
❏ Perform self-diagnostics Enter checks for detected items. AT- 8 5
❏ AT-95, "DTC U1000 CAN COMMUNICATION LINE"
❏ AT-99, "DTC P0615 START SIGNAL CIRCUIT"
❏ AT-103, "DTC P0700 TCM"
❏ AT-104, "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT-108, "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT-113, "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT-115, "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT-117, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT-119, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT-121, "DTC P1702 TRANSMISSION CONTROL MODULE (RAM)"
❏ AT-122, "DTC P1703 TRANSMISSION CONTROL MODULE (ROM)"
❏ AT-123, "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT-126, "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT-131, "DTC P1716 TURBINE REVOLUTION SENSOR"
❏ AT-133, "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT-135, "DTC P1730 A/T INTERLOCK"
❏ AT-138, "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT-140, "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT-142, "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-144, "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT-146, "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT-148, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT-150, "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-152, "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT-154, "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT-156, "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT-158, "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT-160, "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT-162, "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT-164, "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT-166, "DTC P1846 ATF PRESSURE SWITCH 6"
5❏ Inspect each system for items found to be NG in the self-diagnostics and repair or replace the malfunction
parts.
6❏ Perform all road tests and enter the checks again for the required items.AT- 5 3
7❏ For any remaining NG items, perform the “diagnostics procedure” and repair or replace the malfunction parts.
See the chart for diagnostics by symptoms. (This chart also contains other symptoms and inspection proce-
dures.)AT- 6 0
8❏ Erase the results of the self-diagnostics from the TCM.AT- 3 8

AT-50
TROUBLE DIAGNOSIS
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Inspections Before Trouble DiagnosisECS00CEE
A/T FLUID CHECK
Fluid Leakage and Fluid Level Check

Inspect for fluid leakage and check the fluid level. Refer to AT - 1 3 , "Checking A/T Fluid" .
Fluid Condition Check
Inspect the fluid condition.
STALL TEST
Stall Test Procedure
1. Inspect the amount of engine oil. Replenish the engine oil if necessary.
2. Drive for about 10 minutes to warm up the vehicle so that the A/
T fluid temperature is 50 to 80°C (122 to 176°F). Inspect the
amount of ATF. Replenish if necessary.
3. Securely engage the parking brake so that the tires do not turn.
4. Engine start, apply foot brake, and place selector lever in “D”
position.
5. While holding down the foot brake, gradually press down the
accelerator pedal.
6. Quickly read off the stall speed, then quickly remove your foot
from the accelerator pedal.
CAUTION:
Do not hold down the accelerator pedal for more than 5 sec-
onds during this test.
7. Move the selector lever to the “N” position.
8. Cool down the ATF.
Fluid condition Conceivable Cause Required Operation
Varnished (viscous
varnish state)Clutch, brake
scorchedReplace the ATF and check the A/T
main unit and the vehicle for mal-
functions (wire harnesses, cooler
pipes, etc.)
Milky white or
cloudyWater in the fluidReplace the ATF and check for
places where water is getting in.
Large amount of
metal powder mixed
inUnusual wear of
sliding parts within
A/TReplace the ATF and check for
improper operation of the A/T.
SAT6 3 8A
SAT6 4 7B
SCIA1224E
SAT5 1 4G

TROUBLE DIAGNOSIS
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Judgement of Line Pressure Test
ROAD TEST
Description

The road test inspects overall performance of the A/T and analyzes possible malfunction causes.

The road test is carried out in the following three stages.
1. Check before engine is started. Refer to AT - 5 4
.
2. Check at idle. Refer to AT- 5 4
.
3. Cruise test

Inspect all the items from Part 1 to Part 3. Refer to AT- 5 5 , AT- 5 7 , AT- 5 8 .

Before beginning the road test, check the test procedure and inspection items.

Test all inspection items until the symptom is uncovered. Diagnose NG items when all road tests are com-
plete.
Judgement Possible cause
Idle speedLow for all positions
(P, R, N, D)Possible causes include malfunctions in the pressure supply system and low oil pump output.
For example

Oil pump wear

Pressure regulator valve or plug sticking or spring fatigue

Oil strainer
oil pump
pressure regulator valve passage oil leak

Engine idle speed too low
Only low for a spe-
cific positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.
HighPossible causes include a sensor malfunction or malfunction in the line pressure adjustment func-
tion.
For example

Accelerator pedal position signal malfunction

ATF temperature sensor malfunction

Line pressure solenoid malfunction (sticking in “OFF” state, filter clog, cut line)

Pressure regulator valve or plug sticking
Stall speedOil pressure does
not rise higher than
the oil pressure for
idle.Possible causes include a sensor malfunction or malfunction in the pressure adjustment function.
For example

Accelerator pedal position signal malfunction

TCM breakdown

Line pressure solenoid malfunction (shorting, sticking in“ ON” state)

Pressure regulator valve or plug sticking

Pilot valve sticking or pilot filter clogged
The pressure rises,
but does not enter
the standard posi-
tion.Possible causes include malfunctions in the pressure supply system and malfunction in the pres-
sure adjustment function.
For example

Accelerator pedal position signal malfunction

Line pressure solenoid malfunction (sticking, filter clog)

Pressure regulator valve or plug sticking

Pilot valve sticking or pilot filter clogged
Only low for a spe-
cific positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.

AT-54
TROUBLE DIAGNOSIS
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Check Before Engine is StartedECS00CEF
1. CHECK AT CHECK INDICATOR LAMP
1. Park vehicle on level surface.
2. Move selector lever to “P” position.
3. Turn ignition switch to “OFF” position and wait at least 10 seconds.
4. Turn ignition switch to “ON” position. (Do not start engine.)
Does AT CHECK indicator lamp light up for about 2 seconds?
YES >> 1. Turn ignition switch to “OFF” position.
2. Carry out the self-diagnostics and record all NG items on the diagnostics worksheet. Refer to
AT - 8 5
.
3. Go to AT- 5 4 , "
Check at Idle" .
NO >> Stop the road test and go to AT-180, "
A/T CHECK Indicator Lamp Does Not Come On" .
Check at Idle ECS00CEG
1. CHECK STARTING THE ENGINE
1. Park vehicle on level surface.
2. Move selector lever to “P” or “N” position.
3. Turn ignition switch to “OFF” position.
4. Turn ignition switch to “START” position.
Does the engine start?
YES >> GO TO 2.
NO >> Stop the road test and go to AT-180, "
Engine Cannot Be Started In “P” or “N” Position" .
2. CHECK STARTING THE ENGINE
1. Turn ignition switch to “ON” position.
2. Move selector lever in “D”,“4”, “3”, “2”, “1” or “R” position.
3. Turn ignition switch to “START” position.
Does the engine start in either position?
YES >> Stop the road test and go to AT-180, "Engine Cannot Be Started In “P” or “N” Position" .
NO >> GO TO 3.
3. CHECK “P” POSITION FUNCTIONS
1. Move selector lever to “P” position.
2. Turn ignition switch to “OFF” position.
3. Release the parking brake.
4. Push the vehicle forward or backward.
5. Engage the parking brake.
When you push the vehicle with disengaging the parking brake, does it move?
YES >> Enter a check mark at “In “P” Position Vehicle Moves When Pushed” on the diagnostics work-
sheet, then continue the road test.
NO >> GO TO 4.

TROUBLE DIAGNOSIS
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4. CHECK “N” POSITION FUNCTIONS
1. Start the engine.
2. Move selector lever to “N” position.
3. Release the parking brake.
Does vehicle move forward or backward?
YES >> Enter a check mark at “In “N” Position Vehicle Moves” on the diagnostics worksheet, then con-
tinue the road test.
NO >> GO TO 5.
5. CHECK SHIFT SHOCK
1. Engage the brake.
2. Move selector lever to “D” position.
When the transmission is shifted from
“N” to “D”, is there an excessive shock?
YES >> Enter a check mark at “Large Shock ("N" to "D" Position) on the diagnostics worksheet, then con-
tinue the road test.
NO >> GO TO 6.
6. CHECK “R” POSITION FUNCTIONS
1. Engage the brake.
2. Move selector lever to “R” position.
3. Release the brake for 4 to 5 seconds.
Does the vehicle creep backward?
YES >> GO TO 7.
NO >> Enter a check mark at “Vehicle Does Not Creep Backward In "R" Position” on the diagnostics
worksheet, then continue the road test.
7. CHECK “D” POSITION FUNCTIONS
Inspect whether the vehicle creeps forward when the transmission is put into the “D” position.
Does the vehicle creep forward in the
“D” positions?
YES >> Go to AT- 5 5 , "Cruise Test - Part 1" , AT-57, "Cruise Test - Part 2" , and AT-58, "Cruise Test - Part
3" .
NO >> Enter a check mark at “Vehicle Does Not Creep Forward in "D" Position” on the diagnostics work-
sheet, then continue the road test.
Cruise Test - Part 1ECS00CEH
1. CHECK STARTING OUT FROM D1
1. Drive the vehicle for about 10 minutes to warm up the engine oil and ATF.
Appropriate temperature for the ATF: 50 - 80°C (122 - 176°F)
2. Park the vehicle on a level surface.
3. Move selector lever to “P” position.
4. Start the engine.
5. Move selector lever to “D” position.
6. Press the accelerator pedal about half way down to accelerate the vehicle.
With CONSULT-II
Read off the gear positions.
Starts from D1?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle Cannot be Started From D1” on the diagnostics worksheet, then
continue the road test.