Ins INFINITI QX56 2004 Factory Service Manual

TROUBLE DIAGNOSES FOR SYMPTOMS
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TROUBLE DIAGNOSES FOR SYMPTOMSPFP:99999
Load Leveling Rear Air Suspension System Does Not OperateEES0011D
1. CHECK WARNING LAMP ACTIVATION
Make sure warning lamp remains off while driving.
OK or NG
OK >> GO TO 2.
NG >> Carry out self-diagnosis. Refer to RSU-14, "
SELF-DIAGNOSIS" .
2. CHECK FUSES

Check that the following fuses are not blown.
OK or NG
OK >> GO TO 3.
NG >> If fuse is blown, be sure to eliminate cause of blown fuse before installing new fuse. Refer to PG-
4, "POWER SUPPLY ROUTING CIRCUIT" .
3. CHECK SUSPENSION CONTROL UNIT POWER AND GROUND
1. Turn the ignition switch ON.
2. Check voltage between suspension control unit connector B3
terminal 6 (G/R) and ground and between suspension control
unit connector B3 terminal 7 (W/L) and ground.
3. Turn ignition switch OFF.
4. Check resistance between suspension control unit connector B3
terminal 16 (B) and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair the circuit.
Unit Terminals Signal name Fuse or Fusible Link
Suspension control unit6 Ignition switch ON or START 12 (10A)
7
Battery power29 (10A)
Compressor motor relay 5 g (30A)
Combination meter24 Ignition switch ON or START 14 (10A)
8 Battery power 19 (10A)
Voltage : Approx. 12V
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Continuity should exist.
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RSU-26
REAR SUSPENSION ASSEMBLY
Revision: August 20072004 QX56
Rear Load Leveling Air Suspension System
On-Vehicle Inspection and ServiceEES0011G
Check all of the component mountings for any excessive looseness, or back lash. Check the components for
any excessive wear, damage, or abnormal conditions. Repair or replace the components as necessary.
SHOCK ABSORBER INSPECTION

Check the shock absorbers for any air leaks or damage, and replace as necessary.

Check the hoses for any air leaks or damage, and replace as necessary.
1. Seat belt latch anchor 2. Stabilizer bar bushing 3. Stabilizer bar clamp
4. Stabilizer bar 5. Connecting rod 6. Front lower link
7. Knuckle 8. Bushing 9. Rear lower link
10. Shock absorber 11. Suspension arm 12. Lower rubber seat
13. Coil spring 14. Upper rubber seat 15. Rear suspension member
16. Spare tire bracket 17. Bound bumper
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1. Rear load leveling air suspension
hose, RH2. Shock absorber, RH 3. Height sensor
4. Rear load leveling air suspension
hose, LH5. Shock absorber, LH 6. Rear load leveling air suspension
compressor assembly

REAR SUSPENSION ASSEMBLY
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Wheel Alignment InspectionEES0011H
Rear Wheel Alignment Adjusting Bolts
PRELIMINARY INSPECTION
WA RN ING:
Always adjust the alignment with the vehicle on a flat surface. Use CONSULT-II "EXHAUST SOLE-
NOID" active test to release the air pressure from the rear load leveling air suspension system.
NOTE:
If alignment is out of specification, inspect and replace any damaged or worn rear suspension parts before
making any adjustments.
1. Check and adjust the wheel alignment with the vehicle under unladen conditions. “Unladen conditions”
means that the fuel, coolant, and lubricant are full; and that the spare tire, jack, hand tools and mats are in
their designated positions.
2. Check the tires for incorrect air pressure and excessive wear.
3. Check the wheels for runout and damage. Refer to WT-4, "
Inspection" .
4. Check the wheel bearing axial end play.
5. Check the shock absorbers. Refer to RSU-26, "
SHOCK ABSORBER INSPECTION" .
6. Check each mounting point of the suspension components for any excessive looseness or damage.
7. Check each link, arm, and the rear suspension member for any damage.
8. Check the vehicle height. Refer to RSU-48, "
Wheelarch Height (Unladen*1 )" .

Verify the vehicle height using Consult-II memory register 1103 and set to 0 ± 10 mm (0 ± 0.39 in) as
necessary.
GENERAL INFORMATION AND RECOMMENDATIONS
1. A Four-Wheel Thrust Alignment should be performed.

This type of alignment is recommended for any NISSAN vehicle.

The four-wheel “thrust” process helps ensure that the vehicle is properly aligned and the steering wheel
is centered.

The alignment machine itself should be capable of accepting any NISSAN vehicle.

The alignment machine should be checked to ensure that it is level.
2. Make sure the alignment machine is properly calibrated.

Your alignment machine should be regularly calibrated in order to give correct information.
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1. Rear lower link adjusting bolt, LH 2. Front lower link adjusting bolt, LH 3. Front lower link adjusting bolt, RH
4. Rear lower link adjusting bolt, RH
Axial end play : 0 mm (0 in)

RSU-28
REAR SUSPENSION ASSEMBLY
Revision: August 20072004 QX56

Check with the manufacturer of your specific alignment machine for their recommended Service/Cali-
bration Schedule.
THE ALIGNMENT PROCESS
IMPORTANT: Use only the alignment specifications listed in this Service Manual. Refer to RSU-47, "Wheel
Alignment" .
1. When displaying the alignment settings, many alignment machines use “indicators”: (Green/red, plus or
minus, Go/No Go). Do NOT use these indicators.

The alignment specifications programmed into your alignment machine that operate these indicators
may not be correct.

This may result in an ERROR.
2. Some newer alignment machines are equipped with an optional “Rolling Compensation” method to “com-
pensate” the sensors (alignment targets or head units). Do NOT use this “Rolling Compensation”
method.

Use the “Jacking Compensation” method. After installing the alignment targets or head units, raise the
vehicle and rotate the wheels 1/2 turn both ways.

See Instructions in the alignment machine you are using for more information.
CAMBER
1. Measure camber of both the right and left wheels with a suitable
alignment gauge and adjust as necessary to specification.
2. If outside of the specified value, adjust the camber using the
adjusting bolt in the front lower link.
CAUTION:
After adjusting the camber then check the toe-in.
NOTE:
Camber changes about 5' minutes with each graduation of the
adjusting bolt.
3. Tighten the adjusting bolt nuts to specification.
TOE-IN
1. Bounce the rear of the vehicle up and down two to three times to stabilize the vehicle height. Refer to
RSU-48, "
Wheelarch Height (Unladen*1 )" .
2. Push the vehicle straight ahead about 5 m (16 ft).
3. Put a mark on the base line of the tread (rear side) of both of the
tires at the same height as the center of the hub. This will be the
measuring points.
4. Measure the distance “A” (rear side) across from tire to tire.Camber : Refer to RSU-47, "
Wheel Alignment" .
SRA0 96 A
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RSU-30
REAR SUSPENSION MEMBER
Revision: August 20072004 QX56
REAR SUSPENSION MEMBERPFP:55501
Removal and InstallationEES0011I
Rear Suspension
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RSU-32
REAR SUSPENSION MEMBER
Revision: August 20072004 QX56
4. Disconnect the rear load leveling air suspension hoses at the
rear load leveling air suspension compressor assembly.

To disconnect the hoses, push in on the lock ring using a suit-
able tool and pull the hose out.
5. Remove both of the rear wheel and tire assemblies using power
tool.
6. Remove the brake caliper without disconnecting the brake
hoses, using power tool. Reposition the brake caliper out of the
way using a suitable wire. Refer to BR-28, "
Removal and Instal-
lation of Brake Caliper Assembly and Disc Rotor" .
CAUTION:

Do not crimp or stretch the brake hose when repositioning the brake caliper out of the way.

Do not press brake pedal while the brake caliper is removed.
7. Remove the spare tire.
8. Disconnect the two rear ABS sensor electrical connectors.
9. Remove the two rear drive shafts. Refer to RAX-7, "
Removal and Installation" .
10. Remove the rear final drive. Refer to RFD-10, "
REAR FINAL DRIVE ASSEMBLY" .
11. Remove the EVAP canister bolt from the top of the rear suspension member.
12. Disconnect the parking brake cables from the brackets on the rear suspension member.
13. Set a suitable jack to support each of the rear lower links and the
coil spring tension.
14. Remove both of the rear lower link outer bolts and lower the jack to remove the rear coil springs.
15. Remove the two bolts to disconnect the seat belt latch anchor
from the rear suspension member.
16. Disconnect both of the connecting rods from the rear stabilizer
bar.
17. Set a suitable jack under the rear suspension member.
18. Remove the six rear suspension member bolts.
19. Slowly lower the jack to remove the rear suspension member,
suspension arm, front and rear lower links and stabilizer bar as
an assembly.
20. If necessary, remove the suspension arm, spare tire bracket,
height sensor, rear load leveling air suspension hoses, stabilizer
bar, knuckle, and front and rear lower links from the rear suspension member.
INSPECTION AFTER REMOVAL
Check the rear suspension member for deformation, cracks, and other damage and replace if necessary.
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REAR SUSPENSION MEMBER
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INSTALLATION
Installation is in the reverse order of removal.

When raising the rear suspension member assembly, use the
locating pins to align the rear suspension member to the vehicle
body.

When installing the upper and lower rubber seats for the rear
coil springs, the arrow embossed on the rubber seats must point
out toward the wheel and tire assembly.

To connect the rear load leveling air suspension hoses, the lock
ring must be fully seated in the fitting. Insert the hose “B” into the
lock ring “A” until the lock ring “A” is touching the hose “B” as
shown. Pull on the hose to check that it is securely inserted.

Perform the final tightening of the nuts and bolts for the links (rubber bushing) under unladen condition
with the tires on level ground.

Check the wheel alignment. Refer to RSU-47, "Wheel Alignment" .
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RSU-34
SHOCK ABSORBER
Revision: August 20072004 QX56
SHOCK ABSORBERPFP:56210
Removal and Installation EES0011J
REMOVAL
1. Remove the wheel and tire assembly using power tool. Refer to WT-6, "Rotation" .
2. Use CONSULT-II “EXHAUST SOLENOID” active test to release the air pressure from the rear load level-
ing air suspension system.
3. Remove the four clips and remove the rear fender protector, front.
4. Disconnect the rear load leveling air suspension hose from the
shock absorber.

To disconnect the hose, push in on the lock ring using a suit-
able tool and pull the air hose out.
5. Remove the shock absorber upper and lower end bolts using
power tool.
6. Remove the shock absorber.
CAUTION:
Do not damage the rubber boot on the shock absorber.
INSTALLATION
Installation is in the reverse order of removal.

Tighten the shock absorber bolts to specification. Refer to RSU-25, "Components" .
INSPECTION AFTER INSTALLATION

Check the shock absorber for any air leaks or damage to the rubber boot.

Check the shock absorber for smooth operation through a full stroke, both compression and extension.

Check piston rod for cracks, deformation or other damage and replace if necessary.
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SUSPENSION ARM
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Removal and Installation EES0011L
REMOVAL
1. Remove the rear suspension member assembly using power tool. Refer to RSU-30, "Removal and Instal-
lation" .
NOTE:
It is necessary to remove the rear suspension member to remove the front upper bolt from the suspension
arm.
2. Remove the shock absorber upper end bolt.
3. Remove the suspension arm upper nuts and bolts on the sus-
pension member side using power tool.
4. Remove the suspension arm pinch bolt and nut on the knuckle
side using power tool.
5. Disconnect the suspension arm from the knuckle using a soft
hammer.
CAUTION:
Do not damage the ball joint with the soft hammer.
6. Remove the suspension arm.
INSPECTION AFTER REMOVAL

Check the suspension arm for damage, cracks, deformation and replace if necessary.

Check the rubber bushing for damage, cracks and deformation. Replace suspension arm assembly if nec-
essary.

Before checking, turn the ball joint at least 10 revolutions so that the ball joint is properly broken in.
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RSU-36
SUSPENSION ARM
Revision: August 20072004 QX56

Check the ball joint. Replace the suspension arm assembly if
any of the following conditions exist:
–Ball stud is worn.
–Joint is hard to swing.
–Play in axial direction is excessive.
NOTE:
Measurement point “A” is at the bolt groove of the ball stud.
INSTALLATION
Installation is in the reverse order of removal.

Tighten the nuts and bolts to specification. Refer to RSU-25, "Components" .

Perform the final tightening of the nuts and bolts for the links (rubber bushings) under unladen condition
with the tires on level ground.

Check the wheel alignment. Refer to RSU-27, "Wheel Alignment Inspection" . Swinging force “A” : Refer to RSU-47, "
Ball Joint" .
Turning force “B” : Refer to RSU-47, "
Ball Joint" .
Vertical end play “C” : Refer to RSU-47, "
Ball Joint" .
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