INFINITI QX56 2008 Factory Service Manual
Manufacturer: INFINITI, Model Year: 2008, Model line: QX56, Model: INFINITI QX56 2008Pages: 4083, PDF Size: 81.73 MB
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TM-184
< ON-VEHICLE MAINTENANCE >
A/T FLUID COOLER
8. Insert the tip of an air gun into the end of the cooler outlet hose.
9. Wrap a shop rag around the air gun tip and end of cooler outlethose.
10. Blow compressed air regulated to 490 - 883 kPa (5 - 9 kg/cm
2
,71 - 128 psi) through the cooler outlet hose to force any remain-
ing A/T fluid into the coffee filter.
11. Remove the coffee filter from the end of the cooler inlet hose.
12. Perform A/T fluid cooler inspection. Refer to TM-182, "
A/T Fluid
Cooler Cleaning".
A/T FLUID COOLER INSPECTION PROCEDURE
1. Inspect the coffee filter for debris.
a. If small metal debris less than 1mm (0.040 in) in size or metal
powder is found in the coffee filter, this is normal. If normal
debris is found, the A/T fluid cooler/radiator can be re-used and
the procedure is ended.
b. If one or more pieces of debris are found that are over 1mm (0.040 in) in size and/or peeled clutch facing material is found in
the coffee filter, the fluid cooler is not serviceable. The A/T fluid
cooler/radiator must be replaced and the inspection procedure is
ended. Refer to CO-15, "
Removal and Installation".
A/T FLUID COOLER FINAL INSPECTION
After performing all procedures, ensure that all remaining oil is cleaned from all components.
InspectionINFOID:0000000004917427
After performing all procedures, ensure that all remaining oil is cleaned from all components.
SCIA3834E
SCIA2967E
SCIA5659E
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STALL TESTTM-185
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STALL TEST
Inspection and JudgmentINFOID:0000000001696156
A/T FLUID CHECK
Fluid Leakage and Fluid Level Check
• Inspect for fluid leakage and check the fluid level. Refer to TM-178, "Checking the A/T 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.
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 plac-
es 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 im-
proper operation of the A/T.
SAT638A
SAT647B
SCIA1224E
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TM-186
< ON-VEHICLE MAINTENANCE >
STALL TEST
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. 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
Stall speed: 2,350 - 2,650 rpm
SAT514G
Selector lever position
Expected problem location
DR
Stall rotation HO
• Forward brake
• Forward one-way clutch
• 1st one-way clutch
• 3rd one-way clutch
O H • Reverse brake
L L • Engine and torque converter one-way clutch
H H • Line pressure low
Does not shift-up D position 1 → 2 Slipping in 2GR, 3GR, 4GR Direct clutch slippage
Does not shift-up D position 2 → 3 Slipping in 3GR, 4GR, 5GR High and low reverse clutch slippage
Does not shift-up D position 3 → 4 Slipping in 4GR, 5GR Input clutch slippage
Does not shift-up D position 4 → 5 Slipping in 5GR Front brake slippage
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LINE PRESSURE TESTTM-187
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LINE PRESSURE TEST
Inspection and JudgmentINFOID:0000000001696157
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.
3. After warming up remove the oil pressure detection plug and install the Tool.
CAUTION:
When using the oil pressure ga uge, 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.
SCIA2187E
SCIA5309E
SCIA1224E
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TM-188
< ON-VEHICLE MAINTENANCE >
LINE PRESSURE TEST
5. Start the engine, then measure the line pressure at both idle andthe stall speed.
CAUTION:
• Keep the brake pedal pressed all the way down duringmeasurement.
• When measuring the line pressure at the stall speed, refer
to TM-185, "
Inspection and Judgment".
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
Judgement of Line Pressure Test
Oil pressure detection
plug :7.3 N·m (0.74 kg-m, 65 in-lb)SAT493G
Engine speed
Line pressure [kPa (kg/cm
2, 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)
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
Sta ll sp ee d 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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ROAD TESTTM-189
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ROAD TEST
DescriptionINFOID:0000000001696158
ROAD TEST
• 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 TM-189
.
2. Check at idle. Refer to TM-189
.
3. Cruise test • Inspect all the items from Part 1 to Part 3. Refer to TM-190
, TM-192, TM-193.
• Before beginning the road test, check the test procedure and inspection items.
• Test all inspection items until the symptom is uncov ered. Diagnose NG items when all road tests are com-
plete.
Check Before Engine Is StartedINFOID:0000000001696159
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 toTM-32, "
CONSULT-III Function (TRANSMISSION)".
3. Go to TM-189, "
Check At Idle".
NO >> Stop the road test and go to TM-118, "
A/T Check Indicator Lamp Does Not Come On".
Check At IdleINFOID:0000000001696160
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 TM-118, "
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 TM-118, "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?
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TM-190
< ON-VEHICLE MAINTENANCE >
ROAD TEST
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.
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 TM-190, "Cruise Test - Part 1", TM-192, "Cruise Test - Part 2", and TM-193, "Cruise Test -
Part 3".
NO >> Enter a check mark at “Vehicle Does Not Cr eep Forward in "D" Position” on the diagnostics work-
sheet, then continue the road test.
Cruise Test - Part 1INFOID:0000000001696161
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-III
Read off the gear positions.
Starts from D1?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle Cannot be St arted From D1” on the diagnostics worksheet, then
continue the road test.
2.CHECK SHIFT-UP D1 → D2
Press down the accelerator pedal about half way and inspect if the vehicle shifts up (D1 → D2) at the appropri-
ate speed.
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ROAD TESTTM-191
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• Refer to TM-291, "Vehicle Speed at Which Gear Shifting Occurs".
With CONSULT-III
Read the gear position, throttle degree of opening, and vehicle speed.
Does the A/T shift-up D1
→ D2 at the correct speed?
YES >> GO TO 3.
NO >> Enter a check mark at “A/T Does Not Shift: D1 → D2” on the diagnostics worksheet, then continue
the road test.
3.CHECK SHIFT-UP D2 → D3
Press down the accelerator pedal about half way and inspect if the vehicle shifts up (D2 → D3) at the appropri-
ate speed.
• Refer to TM-291, "
Vehicle Speed at Which Gear Shifting Occurs".
With CONSULT-III
Read the gear position, throttle degree of opening, and vehicle speed.
Does the A/T shift-up D2
→ D3 at the correct speed?
YES >> GO TO 4.
NO >> Enter a check mark at “A/T Does Not Shift: D2 → D3” on the diagnostics worksheet, then continue
the road test.
4.CHECK SHIFT-UP D3 → D4
Press down the accelerator pedal about half way and inspect if the vehicle shifts up (D3 → D4) at the appropri-
ate speed.
• Refer to TM-291, "
Vehicle Speed at Which Gear Shifting Occurs".
With CONSULT-III
Read the gear position, throttle degree of opening, and vehicle speed.
Does the A/T shift-up D3
→ D4 at the correct speed?
YES >> GO TO 5.
NO >> Enter a check mark at “A/T Does Not Shift: D3 → D4” on the diagnostics worksheet, then continue
the road test.
5.CHECK SHIFT-UP D4 → D5
Press down the accelerator pedal about half way and inspect if the vehicle shifts up (D4 → D5) at the appropri-
ate speed.
• Refer to TM-291, "
Vehicle Speed at Which Gear Shifting Occurs".
With CONSULT-III
Read the gear position, throttle degree of opening, and vehicle speed.
Does the A/T shift-up D4
→ D5 at the correct speed?
YES >> GO TO 6.
NO >> Enter a check mark at “A/T Does Not Shift: D4 → D5” on the diagnostics worksheet, then continue
the road test.
6.CHECK LOCK-UP
When releasing accelerator pedal from D5, check lock-up from D5 to L/U.
• Refer to TM-291, "
Vehicle Speed at Which Gear Shifting Occurs".
With CONSULT-III
Select “TCC SOLENOID 0.00A” with the “MAIN SIGNAL” mode for A/T.
Does it lock-up?
YES >> GO TO 7.
NO >> Enter a check mark at “A/T Does Not Perform Lock-up” on the diagnostics worksheet, then con-
tinue the road test.
7.CHECK LOCK-UP HOLD
Does it maintain lock-up status?
YES >> GO TO 8.
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TM-192
< ON-VEHICLE MAINTENANCE >
ROAD TEST
NO >> Enter a check mark at “A/T Does Not Hold Lock-up Condition” on the diagnostics worksheet, thencontinue the road test.
8.CHECK LOCK-UP RELEASE
Check lock-up cancellation by depressing brake pedal lightly to decelerate. With CONSULT-III
Select “TCC SOLENOID 0.00A” with the “MAIN SIGNAL” mode for A/T.
Does lock-up cancel?
YES >> GO TO 9.
NO >> Enter a check mark at “Lock-up Is Not Released” on the diagnostics worksheet, then continue the road test.
9.CHECK SHIFT-DOWN D5 → D4
Decelerate by pressing lightly on the brake pedal. With CONSULT-III
Read the gear position and engine speed.
When the A/T shift-down D5
→ D4, does the engine speed drop smoothly back to idle?
YES >> 1. Stop the vehicle. 2. Go to Cruise test - Part 2 (Refer to AT 58).
NO >> Enter a check mark at “Engine Speed Does Not Return to Idle” on the diagnostics worksheet, then continue the road test. Go to Cruise test - Part 2 (Refer to AT 58).
Cruise Test - Part 2INFOID:0000000001696162
1.CHECK STARTING FROM D1
1. Move selector lever the “D” position.
2. Accelerate at half throttle. With CONSULT-III
Read the gear position.
Does it start 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.
2.CHECK SHIFT-UP D1 → D2
Press the accelerator pedal down all the way and ins pect whether or not the transmission shifts up (D1 → D2)
at the correct speed.
• Refer to TM-291, "
Vehicle Speed at Which Gear Shifting Occurs".
With CONSULT-III
Read the gear position, throttle position and vehicle speed.
Does the A/T shift-up D1
→ D2 at the correct speed?
YES >> GO TO 3.
NO >> Enter a check mark at “Vehicle Does Not Shift: D1 → D2” on the diagnostics worksheet, then con-
tinue the road test.
3.CHECK SHIFT-UP D2 → D3
Press the accelerator pedal down all the way and ins pect whether or not the transmission shifts up (D2 → D3)
at the correct speed.
• Refer to TM-291, "
Vehicle Speed at Which Gear Shifting Occurs".
With CONSULT-III
Read the gear position, throttle position and vehicle speed.
Does the A/T shift-up D2
→ D3 at the correct speed?
YES >> GO TO 4.
NO >> Enter a check mark at “Vehicle Does Not Shift: D2 → D3” on the diagnostics worksheet, then con-
tinue the road test.
4.CHECK SHIFT-UP D3 → D4 AND ENGINE BRAKE
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ROAD TESTTM-193
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When the transmission changes speed D3 → D4, return the accelerator pedal.
Does the A/T shift-up D3
→ D4 and apply the engine brake?
YES >> 1. Stop the vehicle. 2. See TM-193, "
Cruise Test - Part 3".
NO >> Enter a check mark at “Vehicle Does Not Shift: D3 → D4” on the diagnostics worksheet, then con-
tinue the road test.
Cruise Test - Part 3INFOID:0000000001696163
1.CHECK SHIFT-DOWN
During D
5 driving, move gear selector from D → 4 → 3 → 2 → 1.
With CONSULT-III
Read the gear position.
Is downshifting correctly performed?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle does not shift” at the corresponding position (5th → 4th, 4th → 3rd,
3rd → 2nd, 2nd → 1st) on the diagnostics worksheet, then continue the road test.
2.CHECK ENGINE BRAKE
Does engine braking effectively reduce speed in 1
1 position?
YES >> 1. Stop the vehicle. 2. Carry out the self-diagnostics. Refer to TM-32, "
CONSULT-III Function (TRANSMISSION)".
NO >> Enter a check mark at “Vehicle Does Not Decelerate By Engine Brake” on the diagnostics work- sheet, then continue trouble diagnosis.
Vehicle Speed When Shifting GearsINFOID:0000000001696164
Refer to TM-193, "Vehicle Speed When Shifting Gears".
Vehicle Speed When Performing and Releasing Complete Lock-upINFOID:0000000001696165
Refer to TM-193, "Vehicle Speed When Performing and Releasing Complete Lock-up".
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