2010 INFINITI QX56 engine control module

BCS
BCM (BODY CONTROL MODULE)BCS-41
< ECU DIAGNOSIS > [BCM]
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LIGHT SW 1ST
Lighting switch OFF OFF
Lighting switch 1st
ON
HEAD LAMP SW1 Headlamp switch OFF
OFF
Headlamp switch 1st ON
HEAD LAMP SW2 Headlamp switch OFF
OFF
Headlamp switch 1st ON
HI BEAM SW High beam switch OFF
OFF
High beam switch HI ON
IGN ON SW Ignition switch OFF or ACC
OFF
Ignition switch ON ON
IGN SW CAN Ignition switch OFF or ACC
OFF
Ignition switch ON ON
INT VOLUME Wiper intermittent dial is in a dial position 1 - 7 1 - 7
I-KEY LOCK LOCK button of Intelligent Key is not pressed
OFF
LOCK button of Intelligent Key is pressed ON
I-KEY UNLOCK UNLOCK button of Intelligent Key is not pressed
OFF
UNLOCK button of Intelligent Key is pressed ON
KEY CYL LK-SW Door key cylinder LOCK position
ON
Door key cylinder other than LOCK position OF
KEY CYL UN-SW Door key cylinder UNLOCK position
ON
Door key cylinder other than UNLOCK position ON
KEY ON SW Mechanical key is removed from key cylinder
OFF
Mechanical key is inserted to key cylinder ON
OIL PRESS SW • Ignition switch OFF or ACC
• Engine running
OFF
Ignition switch ON ON
OPTICAL SENSOR Bright outside of the vehicle
Close to 5V
Dark outside of the vehicle Close to 0V
PASSING SW Other than lighting switch PASS
OFF
Lighting switch PASS ON
PUSH SW Return to ignition switch to LOCK position
OFF
Press ignition switch ON
REAR DEF SW Rear window defogger switch OFF
OFF
Rear window defogger switch ON ON
RR WASHER SW Rear washer switch OFF
OFF
Rear washer switch ON ON
RR WIPER INT Rear wiper switch OFF
OFF
Rear wiper switch INT ON
RR WIPER ON Rear wiper switch OFF
OFF
Rear wiper switch ON ON
RR WIPER STOP Rear wiper stop position
OFF
Other than rear wiper stop position ON
RR WIPER STP2 Rear wiper stop position
OFF
Other than rear wiper stop position ON
Monitor Item
Condition Value/Status
Revision: April 20092010 QX56

BCS-54
< ECU DIAGNOSIS >[BCM]
BCM (BODY CONTROL MODULE)
DTC Inspection Priority Chart
INFOID:0000000005146433
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
DTC IndexINFOID:0000000005146434
NOTE: Details of time display
• CRNT: Displays when there is a malfunction now or after returning to the normal condition until turning igni- tion switch OFF → ON again.
• 1 - 39: Displayed if any previous malfunction is present when current condition is normal. It increases like 1
→ 2 → 3...38 → 39 after returning to the normal condition whenever ignition switch OFF → ON. The counter
remains at 39 even if the number of cycles exceeds it. It is counted from 1 again when turning ignition switch
OFF → ON after returning to the normal condition if the malfunction is detected again.
Display contents of CONS ULTFail-safe Cancellation
U1000: CAN COMM CIRCUIT I nhibit engine crankingWhen the BCM re-establishes communication with the other mod-
ules.
Priority
DTC
1 • U1000: CAN COMM CIRCUIT
2 • B2190: NATS ANTENNA AMP
• B2191: DIFFERENCE OF KEY
• B2192: ID DISCORD BCM-ECM
• B2193: CHAIN OF BCM-ECM
• B2013: STRG COMM 1
• B2552: INTELLIGENT KEY
• B2590: NATS MALFUNCTION
3 • C1729: VHCL SPEED SIG ERR
• C1735: IGNITION SIGNAL
4 • C1708: [NO DATA] FL
• C1709: [NO DATA] FR
• C1710: [NO DATA] RR
• C1711: [NO DATA] RL
• C1712: [CHECKSUM ERR] FL
• C1713: [CHECKSUM ERR] FR
• C1714: [CHECKSUM ERR] RR
• C1715: [CHECKSUM ERR] RL
• C1716: [PRESSDATA ERR] FL
• C1717: [PRESSDATA ERR] FR
• C1718: [PRESSDATA ERR] RR
• C1719: [PRESSDATA ERR] RL
• C1720: [CODE ERR] FL
• C1721: [CODE ERR] FR
• C1722: [CODE ERR] RR
• C1723: [CODE ERR] RL
• C1724: [BATT VOLT LOW] FL
• C1725: [BATT VOLT LOW] FR
• C1726: [BATT VOLT LOW] RR
• C1727: [BATT VOLT LOW] RL
CONSULT display
Fail-safeIntelligent Key
warning lamp ON Tire pressure
monitor warning lamp ON Reference page
No DTC is detected.
further testing
may be required. ————
U1000: CAN COMM CIRCUIT ———BCS-32
B2190: NATS ANTENNA AMP ———SEC-31
Revision: April 20092010 QX56

BCS
PRECAUTIONSBCS-57
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental
Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005384312
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers, always switch the Ignition OFF, disconnect the battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wheel Rotation After Battery Disconnect
INFOID:0000000005282709
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecti ng both battery cables with the ignition knob in the
″ LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS , an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery power is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
Revision: April 20092010 QX56

PRECAUTIONSBR-3
< PRECAUTION >
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005403123
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers, always switch the Ignition OFF, disconnect the battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wheel Rotation After Battery Disconnect
INFOID:0000000005403124
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecti ng both battery cables with the ignition knob in the
″ LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS , an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery power is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
Revision: April 20092010 QX56

BRC-110
< PRECAUTION >[VDC/TCS/ABS]
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint Syst
em (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005403136
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000005403137
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: April 20092010 QX56

PRECAUTIONSBRC-111
< PRECAUTION > [VDC/TCS/ABS]
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5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of al l control units using CONSULT-III.
Precaution for Brake SystemINFOID:0000000005148094
CAUTION:
• Always use recommended brake fluid. Refer to MA-13, "
Fluids and Lubricants".
• Never reuse drained brake fluid.
• Be careful not to splash brake fluid on painted areas; it may cause paint damage. If brake fluid is
splashed on painted areas, wash it away with water immediately.
• To clean or wash all parts of master cylin der and disc brake caliper, use clean brake fluid.
• Never use mineral oils such as gasoline or kerosen e. They will ruin rubber parts of the hydraulic sys-
tem.
• Use flare nut wrench when removing and installing brake
tube.
• If a brake fluid leak is found, the part must be disassembled
without fail. Then it has to be replaced with a new one if a
defect exists.
• Turn the ignition switch OFF and remove the connector of the ABS actuator and electric unit (con trol unit) or the battery ter-
minal before performing the work.
• Always torque brake lines when installing.
• Burnish the brake contact surf aces after refinishing or replac-
ing rotors, after replacing pads, or if a soft pedal occurs at
very low mileage.
Refer to BR-30, "
Brake Burnishing Procedure" (front disc brake) or BR-35, "Brake Burnishing Proce-
dure" (rear disc brake).
WARNING:
• Clean brake pads and shoes with a waste cl oth, then wipe with a dust collector.
Precaution for Brake ControlINFOID:0000000005148095
• During ABS operation, the brake pedal may vibrate lightly and a mechanical noise may be heard. This is
normal.
• Just after starting vehicle, the brake pedal may vibrate or a motor operating noise may be heard from engine
compartment. This is a normal status of operation check.
• Stopping distance may be longer than that of vehicles without ABS when vehicle drives on rough, gravel, or snow-covered (fresh, deep snow) roads.
• When an error is indicated by ABS or another warning lamp, collect all necessary information from customer (what symptoms are present under what conditions) and check for simple causes before starting diagnosis.
Besides electrical system inspection, check boos ter operation, brake fluid level, and fluid leaks.
• If incorrect tire sizes or types are installed on the vehicle or brake pads are not Genuine NISSAN parts, stop-
ping distance or steering stability may deteriorate.
• If there is a radio, antenna or related wiring near control module, ABS function may have a malfunction or
error.
• If aftermarket parts (car stereo, CD player, etc.) have been installed, check for incidents such as harness pinches, open circuits or improper wiring.
• If the following components are replaced with non-genuine components or modified, the VDC OFF indicator lamp and SLIP indicator lamp may turn on or the VDC system may not operate properly. Components
related to suspension (shock absorbers, struts, springs , bushings, etc.), tires, wheels (exclude specified
size), components related to brake system (pads, roto rs, calipers, etc.), components related to engine (muf-
fler, ECM, etc.), components related to body reinforcement (roll bar, tower bar, etc.).
• Driving with broken or excessively worn suspensi on components, tires or brake system components may
cause the VDC OFF indicator lamp and the SLIP indicator lamp to turn on, and the VDC system may not
operate properly.
• When the TCS or VDC is activated by sudden acceleration or sudden turn, some noise may occur. The noise is a result of the normal operation of the TCS and VDC.
• When driving on roads which have extreme slopes (such as mountainous roads) or high banks (such as sharp curves on a freeway), the VDC may not operate no rmally, or the VDC warning lamp and the SLIP indi-
cator lamp may turn on. This is not a problem if normal operation can be resumed after restarting the engine.
SBR686C
Revision: April 20092010 QX56

BRM-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005370276
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000005370277
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: April 20092010 QX56

CHG-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005260140
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000005260141
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: April 20092010 QX56