2007 INFINITI QX56 check engine

TROUBLE DIAGNOSIS
RSU-11
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POWER SYSTEM TERMINAL LOOSENESS AND BATTERY INSPECTION
Make sure the battery positive cable, negative cable and ground connection are not loose. In addition, make
sure the battery is sufficiently charged.
CK SUSP INDICATOR LAMP INSPECTION
1. Make sure the CK SUSP indicator lamp turns on for approximately 2 seconds when the ignition switch is
turned ON. If it does not, check the combination meter. Refer to DI-5
.
2. Make sure the lamp turns off approximately 2 seconds after the ignition switch is turned ON. If the lamp
does not turn off, conduct self-diagnosis of the suspension control unit.
3. After conducting the self-diagnosis, be sure to erase the error memory. Refer to RSU-11, "
CONSULT-II
Function (AIR LEVELIZER)" .
Chek Suspension Indicator Lamp TimingINFOID:0000000003532661
X: ON
—: OFF
Control Unit Input/Output Signal StandardINFOID:0000000003532662
CONSULT-II Function (AIR LEVELIZER)INFOID:0000000003532663
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
CONSULT-II START PROCEDURE
Refer to GI-36, "CONSULT-II Start Procedure".
ConditionCK SUSP
indicator lampRemarks
Ignition switch OFF – –
Ignition switch ON X Turns off after approximately 2 seconds.
Te r m i n a l
No.Wire color Item ConditionVoltage (V)
(Approx.)
1 V Compressor relay output
Ignition switch ON or STARTBattery voltage
3 W Height sensor signal input 0.2V - 4.8V
5 R Reference voltage 5V
6 G/R Ignition power
Battery voltage
7W/LBattery power —
8 G/W Diagnostic K-line — —
9 SB Exhaust valve output Ignition switch ON or START Battery voltage
10 BR Warning lamp output — —
14 L Height sensor ground — —
15 BR/W Generator L signal input Engine running —
16 B Suspension control unit ground — 0V
AIR LEVELIZER
diagnostic modeDescription
WORK SUPPORTSupports inspections and adjustments. Commands are transmitted to the BCM for setting the status
suitable for required operation, input/output signals are received from the BCM and received data is
displayed.
SELF-DIAG RESULTS Displays suspension control unit self-diagnosis results.
DATA MONITOR Displays suspension control unit input/output data in real time.
ACTIVE TEST Operation of electrical loads can be checked by sending drive signal to them.
ECU PART NUMBER Suspension control unit part number can be read.

TROUBLE DIAGNOSES FOR SYMPTOMS
RSU-19
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TROUBLE DIAGNOSES FOR SYMPTOMS
Load Leveling Rear Air Suspension System Does Not OperateINFOID:0000000003532667
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-11, "
CONSULT-II Function (AIR LEVELIZER)" .
2.CHECK FUSES AND FUSIBLE LINK
Check that the following fuses and fusible link are not blown.
OK or NG
OK >> GO TO 3.
NG >> If fuse or fusible link is blown, be sure to eliminate cause of malfunction before installing new fuse
or fusible link.
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 and ground and between suspension control unit con-
nector B3 terminal 7 and ground.
3. Turn the ignition switch OFF.
4. Check continuity between suspension control unit connector B3
terminal 16 and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4.CHECK GENERATOR SIGNAL INPUT
1. Start the engine.
Unit Terminals Signal name Fuse and fusible link No.
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
WEIA0069E
16 - Ground Continuity should exist.
WEIA0070E

REAR SUSPENSION MEMBER
RSU-29
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• 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
(unladen condition means that the fuel tank, engine coolant and lubricants are at the full specification, and
the spare tire, jack, hand tools, and mats are in their designated positions) with the tires on level ground.
• Check the wheel alignment. Refer to FSU-19, "
Wheel Alignment (Unladen*1) *6" .
LEIA0076E
LEIA0078E

RSU-32
< SERVICE INFORMATION >
SUSPENSION ARM
• 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.
INSTALLATION
Installation is in the reverse order of removal.
• Tighten the nuts and bolts to specification. Refer to RSU-21, "
Component" .
• Perform the final tightening of the nuts and bolts for the links (rubber bushing) under unladen condition
(unladen condition means that the fuel tank, engine coolant and lubricants are at the full specification, and
the spare tire, jack, hand tools, and mats are in their designated positions) with the tires on level ground.
• Check the wheel alignment. Refer to RSU-23, "
Wheel AlignmentInspection" . Swinging force “A” : Refer to RSU-43, "
Ball Joint" .
Turning force “B” : Refer to RSU-43, "
Ball Joint" .
Vertical end play “C” : Refer to RSU-43, "
Ball Joint" .
SFA858A

RSU-34
< SERVICE INFORMATION >
FRONT LOWER LINK
• Check the ball joint. Replace the front lower link if any of the follow-
ing conditions exist:
- Ball stud is worn.
- Joint is hard to swing.
- Play in axial direction is excessive.
INSTALLATION
Installation is in the reverse order of removal.
• Tighten the nuts and bolts to specification. Refer to RSU-21, "
Component" .
• Perform the final tightening of the nuts and bolts for the links (rubber bushing) under unladen condition
(unladen condition means that the fuel tank, engine coolant and lubricants are at the full specification, and
the spare tire, jack, hand tools, and mats are in their designated positions) with the tires on level ground.
• Check the wheel alignment. Refer to RSU-23, "
Wheel AlignmentInspection"
Swinging force “A” : Refer to RSU-43, "Ball Joint" .
Turning force “B” : Refer to RSU-43, "
Ball Joint".
Vertical end play “C” : Refer to RSU-43, "
Ball Joint" .
SFA858A

HEIGHT SENSOR
RSU-41
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1. Start the engine.
2. Use CONSULT-II to perform "STANDARD HEIGHT LEVEL" work support function.
3. Using data monitor of CONSULT-II, verify "HEIGT CALC" is at 0 mm.
4. Check the vehicle height. Refer to RSU-44, "
Wheelarch Height (Unladen*1)" . If vehicle height is not within
± 10 mm (0 ± 0.39 in) of the specification, perform the initialization procedure. Refer to RSU-42, "
Initializa-
tion Procedure".

SC-4
< SERVICE INFORMATION >
BATTERY
BATTERY
How to Handle BatteryINFOID:0000000003533316
CAUTION:
• If it becomes necessary to start the engine with a booster battery and jumper cables, use a 12-volt
booster battery.
• After connecting battery cables, ensure that they are tightly clamped to battery terminals for good
contact.
• Never add distilled water through the hole used to check specific gravity.
METHODS OF PREVENTING OVER-DISCHARGE
The following precautions must be taken to prevent over-discharging
a battery.
• The battery surface (particularly its top) should always be kept
clean and dry.
• The terminal connections should be clean and tight.
• At every routine maintenance, check the electrolyte level.
This also applies to batteries designated as “low maintenance” and
“maintenance-free”.
• When the vehicle is not going to be used over a long period of
time, disconnect the negative battery terminal.
• Check the charge condition of the battery.
Periodically check the specific gravity of the electrolyte. Keep a
close check on charge condition to prevent over-discharge.
CHECKING ELECTROLYTE LEVEL
WARNING:
Do not allow battery fluid to come in contact with skin, eyes, fabrics, or painted surfaces. After touch-
ing a battery, do not touch or rub your eyes until you have thoroughly washed your hands. If acid con-
tacts eyes, skin or clothing, immediately flush with water for 15 minutes and seek medical attention.
MEL040F
MEL041F
MEL042F

SC-12
< SERVICE INFORMATION >
STARTING SYSTEM
DIAGNOSTIC PROCEDURE 1
Check Starter Motor Circuit
1.CHECK POWER SUPPLY TO STARTER MOTOR
1. Remove the fuel pump fuse.
2. Crank or start the engine (where possible) until the fuel pressure is released.
3. Turn the ignition switch OFF.
*1SC-6, "Trouble Diagnosis with Bat-
tery/Starting/Charging System
Te s t e r"
*2 "MINIMUM SPECIFICATION OF
CRANKING VOLTAGE REFERENC-
ING COOLANT TEMPERATURE"*3 "DIAGNOSTIC PROCEDURE 1"
*4 "DIAGNOSTIC PROCEDURE 2"
WKIA4532E