INFINITI QX56 2006 Factory Service Manual

AT-46
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
DIAGNOSTIC WORKSHEET
Information From Customer
KEY POINTS

WHAT..... Vehicle & A/T model

WHEN ..... Date, Frequencies

WHERE ..... Road conditions

HOW..... Operating conditions, Symptoms
Diagnostic Worksheet Chart
Customer name MR/MS Model & Year VIN
Trans. Model EngineMileage
Malfunction Date Manuf. DateIn Service Date
Frequency ❏ Continuous ❏ Intermittent ( times a day)
Symptoms ❏ Vehicle does not move. ( ❏ Any position ❏ Particular position)
❏ No up-shift ( ❏ 1st → 2nd ❏ 2nd → 3rd❏ 3rd → 4th ❏ 4th → 5th)
❏ No down-shift ( ❏ 5th → 4th ❏ 4th → 3rd ❏ 3rd → 2nd ❏ 2nd → 1st)
❏ Lock-up malfunction
❏ Shift point too high or too low.
❏ Shift shock or slip ( ❏ N → D ❏ Lock-up ❏ Any drive position)
❏ Noise or vibration
❏ No kick down
❏ No pattern select
❏ Others
()
Malfunction indicator lamp (MIL) ❏ Continuously lit ❏ Not lit
1 ❏ Read the item on cautions concerning fail-safe and understand the customer's complaint. AT- 4 2
2❏
ATF inspection
AT- 5 1❏ Leak (Repair leak location.)
❏ State
❏ Amount
3 ❏
Stall test and line pressure test
AT- 5 1
, AT-
52
❏ Stall test
❏ Torque converter one-way clutch
❏ Front brake
❏ High and low reverse clutch
❏ Low coast brake
❏ Forward brake
❏ Reverse brake
❏ Forward one-way clutch ❏
1st one-way clutch
❏ 3rd one-way clutch
❏ Engine
❏ Line pressure low
❏ Except for input clutch and direct
clutch, clutches and brakes OK
❏ Line pressure inspection - Suspected part:

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4❏
Perform all road tests and enter checks in required inspection items. AT- 5 4
4-1.Check before engine is started
AT- 5 5
❏ AT- 1 7 9 , "A/T CHECK Indicator Lamp Does Not Come On" .
❏ Perform self-diagnostics Enter checks for detected items. AT- 8 6
❏ AT-96, "DTC U1000 CAN COMMUNICATION LINE"
❏ AT-100, "DTC P0615 START SIGNAL CIRCUIT"
❏ AT-104, "DTC P0700 TCM"
❏ AT-105, "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT-109, "DTC P0717 TURBINE REVOLUTION SENSOR"
❏ AT- 111 , "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT-116, "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT-118, "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT-120, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT-122, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT-124, "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT-127, "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT-132, "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT-134, "DTC P1730 A/T INTERLOCK"
❏ AT-137, "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT-139, "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT-141, "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-143, "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT-145, "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT-147, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT-149, "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-151, "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT-153, "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT-155, "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT-157, "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT-159, "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT-161, "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT-163, "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT-165, "DTC P1846 ATF PRESSURE SWITCH 6"
4-2. Idle inspection
AT- 5 5
❏ AT- 1 7 9 , "Engine Cannot Be Started In “P” or “N” Position"
❏ AT- 1 8 0 , "In “P” Position, Vehicle Moves When Pushed"
❏ AT- 1 8 1 , "In “N” Position, Vehicle Moves"
❏ AT- 1 8 2 , "Large Shock (“N” to “D” Position)"
❏ AT- 1 8 6 , "Vehicle Does Not Creep Backward In “R” Position"
❏ AT- 1 8 9 , "Vehicle Does Not Creep Forward In “D” Position"
4-3. Driving tests
AT- 5 6
Part 1
❏ AT- 1 9 1 , "
Vehicle Cannot Be Started From D1"
❏ AT- 1 9 4 , "A/T Does Not Shift: D1 → D2"
❏ AT- 1 9 6 , "A/T Does Not Shift: D2 → D3"
❏ AT- 1 9 8 , "A/T Does Not Shift: D3 → D4"
❏ AT- 2 0 1 , "A/T Does Not Shift: D4 → D5"
❏ AT- 2 0 3 , "A/T Does Not Perform Lock-up"
❏ AT- 2 0 5 , "A/T Does Not Hold Lock-up Condition"
❏ AT- 2 0 7 , "Lock-up Is Not Released"
❏ AT- 2 0 8 , "Engine Speed Does Not Return to Idle"

AT-48
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
44-3Part 2
AT- 5 8
❏ AT-191, "Vehicle Cannot Be Started From D1"
❏ AT-194, "A/T Does Not Shift: D1 → D2"
❏ AT-196, "A/T Does Not Shift: D2 → D3"
❏ AT-198, "A/T Does Not Shift: D3 → D4"
Part 3
AT- 5 9
❏ AT-209, "A/T Does Not Shift: 5th gear → 4th gear"
❏ AT-212, "A/T Does Not Shift: 4th gear → 3rd gear"
❏ AT-213, "A/T Does Not Shift: 3rd gear → 2nd gear"
❏ AT-215, "A/T Does Not Shift: 2nd gear → 1st gear"
❏ AT-218, "Vehicle Does Not Decelerate By Engine Brake"
❏ Perform self-diagnostics Enter checks for detected items. AT- 8 6
❏ AT- 9 6 , "DTC U1000 CAN COMMUNICATION LINE"
❏ AT-100, "DTC P0615 START SIGNAL CIRCUIT"
❏ AT-104, "DTC P0700 TCM"
❏ AT-105, "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT-109, "DTC P0717 TURBINE REVOLUTION SENSOR"
❏ AT- 111 , "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT- 11 6 , "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT- 11 8 , "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT-120, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT-122, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT-124, "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT-127, "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT-132, "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT-134, "DTC P1730 A/T INTERLOCK"
❏ AT-137, "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT-139, "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT-141, "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-143, "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT-145, "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT-147, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT-149, "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-151, "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT-153, "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT-155, "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT-157, "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT-159, "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT-161, "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT-163, "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT-165, "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 4
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 1
8
❏ Erase the results of the self-diagnostics from the TCM. AT- 3 9

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A/T Electrical Parts LocationECS00CEC
WCIA0515E

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Circuit DiagramECS00CED
BCWA0496E

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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 2 , "Changing Automatic Transmission
Fluid (ATF)" .
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.
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
cloudy Water in the fluidReplace the ATF and check for
places where water is getting in.
Large amount of
metal powder mixed
in Unusual wear of
sliding parts within
A/T
Replace the ATF and check for
improper operation of the A/T.
SAT638A
SAT647B
SCIA1224E
SAT514G

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TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
8. Cool down the ATF.
CAUTION:
Run the engine at idle for at least one minute.
Judgement of Stall Test
O: Stall speed within standard value position
H: Stall speed higher than standard value
L: Stall speed lower than standard value
Stall test standard value position
LINE PRESSURE TEST
Line Pressure Test Port
Line Pressure Test Procedure
1. Inspect the amount of engine oil and replenish if necessary.
2. Drive the car for about 10 minutes to warm it up so that the ATF reaches in range of 50 to 80 °C (122 to
176° F), then inspect the amount of ATF and replenish if necessary.
NOTE:
The automatic fluid temperature rises in range of 50 to 80 °C (122 to 176 °F) during 10 minutes of
driving. Stall speed: 2,500 - 2,800 rpm
Selector lever position
Expected problem location
DR
Stall rotation HO

Forward brake

Forward one-way clutch

1st one-way clutch

3rd one-way clutch
OH

Reverse brake
LL

Engine and torque converter one-way clutch
HH

Line pressure low
Does not shift-up D position 1 → 2 Slipping in 2nd, 3rd, 4th gears Direct clutch slippage
Does not shift-up D position 2 → 3 Slipping in 3rd, 4th, 5th gears High and low reverse clutch slippage
Does not shift-up D position 3 → 4 Slipping in 4th, 5th gears Input clutch slippage
Does not shift-up D position 4 → 5 Slipping in 5th gear Front brake slippage
SCIA2187E

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3. After warming up remove the oil pressure detection plug and
install the oil pressure gauge [ST2505S001(J-34301-C)].
CAUTION:
When using the oil pressure gauge, be sure to use the O-
ring attached to the oil pressure detection plug.
4. Securely engage the parking brake so that the tires do not turn.
5. Start the engine, then measure the line pressure at both idle and the stall speed.
CAUTION:

Keep the brake pedal pressed all the way down during
measurement.

When measuring the line pressure at the stall speed,
refer to AT- 5 1 , "
STALL TEST" .
6. After the measurements are complete, install the oil pressure detection plug and tighten to the regulation torque below.
CAUTION:
Do not reuse the O-ring.
Line Pressure
SCIA5309E
SCIA1224E
:7.3 N·m (0.74 kg-m, 65 in-lb)SAT493G
Engine speed Line pressure [kPa (kg/cm2 , psi)]
R position D position
At idle speed 425 - 465 (4.3 - 4.7, 62 - 67) 379 - 428 (3.9 - 4.4, 55 - 62)
At stall speed 1,605 - 1,950 (16.4 - 19.9, 233 - 283) 1,310 - 1,500 (13.4 - 15.3, 190 - 218)

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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 5
.
2. Check at idle. Refer to AT- 5 5
.
3. Cruise test

Inspect all the items from Part 1 to Part 3. Refer to AT- 5 6 , AT- 5 8 , AT- 5 9 .

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 speed Low 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 position Possible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.
High Possible 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 speed Oil 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 position Possible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.

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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 6
.
3. Go to AT- 5 5 , "
Check at Idle" .
NO >> Stop the road test and go to AT- 1 7 9 , "
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- 1 7 9 , "
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- 1 7 9 , "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.