2011 INFINITI QX56 air conditioning

PRECAUTIONSGI-31
< PRECAUTION >
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Dispose of used oil and used oil filters through authorized waste disposal contractors to licensed waste dis-
posal sites, or to the waste oil reclamation trade. If in doubt, contact the local authority for advice on disposal
facilities.
It is illegal to pour used oil on to the ground, dow n sewers or drains, or into water sources.
The regulations concerning po llution vary between regions.
Air ConditioningINFOID:0000000006280875
Use an approved refrigerant recovery unit any time t he air conditioning system must be discharged. Refer to
HA section “REFRIGERANT” fo r specific instructions.
FuelINFOID:0000000006280876
INFINITI recommends the use of unleaded premium gasoli ne with an octane rating of at least 91 AKI (Anti-
Knock Index) number (Research octane number 96).
If unleaded premium gasoline is not available, unleaded r egular gasoline with an octane rating of at least 87
AKI number (Research octane number 91), can be used. In such case, engine performance may be decrease.
CAUTION:
 Using a fuel other than that specified could ad versely affect the emission control system, and may
also affect warranty coverage.
 Under no circumstances should a leaded gasoline be used, because this will damage the three-way
catalyst.
 Do not use E-85 fuel in the vehicle . The vehicle is not designed to run on E-85 fuel. Using E-85 fuel
can damage the fuel system components and is not covered by the INFINITI vehicle limited warranty.
Revision: 2010 May2011 QX56

INSPECTION AND ADJUSTMENTGI-65
< BASIC INSPECTION >
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O PINSPECTION AND ADJUSTMENT
ADDITIONAL SERVICE WHEN REMOVING BATTERY NEGATIVE TERMINAL
ADDITIONAL SERVICE WHEN REMOVING BATTERY NEGATIVE TERMINAL : Re-
quired Procedure After Battery Disconnection
INFOID:0000000006344676
*: Not equipped. SYSTEM ITEM REFERENCE
Front automatic air
conditioning system Temperature setting trimmer (Front)
HAC-68, "
FRONT AUTOMATIC
AIR CONDITIONING SYSTEM :
Temperature Setting Trimmer
(Front)"
Foot position setting trimmer
HAC-68, "
FRONT AUTOMATIC
AIR CONDITIONING SYSTEM :
Foot Position Setting Trimmer"
Inlet port memory function* —
Inlet port memory function (FRE)
HAC-69, "
FRONT AUTOMATIC
AIR CONDITIONING SYSTEM :
Inlet Port Memory
Function (FRE)"
Inlet port memory function (REC) HAC-69, "
FRONT AUTOMATIC
AIR CONDITIONING SYSTEM :
Inlet Port Memory Function (REC)"
ACCS (Advanced Cli-
mate Control System)Exhaust gas / outside odor detecting sensor sensitivity adjustment func-
tion
HAC-70, "
ACCS (ADVANCED
CLIMATE CONTROL SYSTEM) :
Exhaust Gas / Outside Odor De-
tecting Sensor Sensitivity Adjust-
ment Function"
Auto intake switch interlocking movement change function
HAC-70, "
ACCS (ADVANCED
CLIMATE CONTROL SYSTEM) :
Auto Intake Switch Interlocking
Movement Change Function"
Clean switch interlocking movement change function* —
Rear automatic air
conditioning system Temperature setting trimmer (Rear) HAC-69, "
REAR AUTOMATIC AIR
CONDITIONING SYSTEM : Tem-
perature Setting
Trimmer (Rear)"
Automatic drive posi-
tioner Automatic drive positioner system ADP-51, "
ADDITIONAL SERVICE
WHEN REMOVING BATTERY
NEGATIVE TERMINAL : Descrip-
tion"
Power window control Power window control system
PWC-31, "Description"
Sunroof system* Sunroof system —
Sunshade system* Sunshade system —
Rear view monitor* Rear view monitor predictive course line center position adjustment —
Around view monitor Predictive course line center position adjustment AV- 111 , "
Description"
Automatic back door
systemAutomatic back door system DLK-80, "
ADDITIONAL SERVICE
WHEN REMOVING BATTERY
NEGATIVE TERMINAL : Descrip-
tion"
Engine oil level read* Engine oil level read —
Revision: 2010 May2011 QX56

HA-1
VENTILATION, HEATER & AIR CONDITIONER
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SECTION HA
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CONTENTS
HEATER & AIR CONDITIONING SYSTEM
PRECAUTION ................ ...............................3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect .....................................
3
Precaution for Procedure without Cowl Top Cover ......4
Precautions For Refrigerant System Service ............4
Service Equipment ....................................................6
PREPARATION ............................................9
PREPARATION .............................................. .....9
Special Service Tool ........................................... ......9
Commercial Service Tool ........................................12
Sealant or/and Lubricant .........................................12
SYSTEM DESCRIPTION .............................13
COMPONENT PARTS ................................... ....13
Component Parts Location .................................. ....13
Component Description ...........................................13
SYSTEM .............................................................14
System Diagram .................................................. ....14
System Description .................................................14
BASIC INSPECTION ...................................16
DIAGNOSIS AND REPAIR WORKFLOW ..... ....16
Work Flow ........................................................... ....16
REFRIGERANT ..................................................18
Description .......................................................... ....18
Leak Test ................................................................18
Recycle Refrigerant .................................................20
Charge Refrigerant ..................................................20
LUBRICANT ................................................... ....22
Description .......................................................... ....22
Inspection ............................................................ ....22
Perform Lubricant Return Operation .......................22
Lubricant Adjusting Procedure for Components
Replacement Except Compressor ...........................
22
Lubricant Adjusting Procedure for Compressor
Replacement ...........................................................
23
PERFORMANCE TEST ....................................25
Inspection ................................................................25
SYMPTOM DIAGNOSIS ..............................27
REFRIGERATION SYSTEM SYMPTOMS ........27
Trouble Diagnosis For Unusual Pressure ............ ....27
Symptom Table .......................................................27
NOISE ................................................................29
Symptom Table .......................................................29
REMOVAL AND INSTALLATION ...............30
COMPRESSOR .................................................30
Exploded View ..................................................... ....30
COMPRESSOR ..........................................................30
COMPRESSOR : Removal and Installation ............30
MAGNET CLUTCH ................................................ ....31
MAGNET CLUTCH : Removal and Installation of
Compressor Clutch ..................................................
31
Inspection ................................................................32
COOLER PIPE AND HOSE ..............................33
Exploded View .........................................................33
HIGH-PRESSURE FLEXIBLE HOSE ........................34
HIGH-PRESSURE FLEXIBLE HOSE : Removal
and Installation .................................................... ....
34
LOW-PRESSURE FLEXIBLE HOSE ..................... ....35
LOW-PRESSURE FLEXIBLE HOSE : Removal
and Installation ........................................................
35
HIGH-PRESSURE PIPE ............................................35
Revision: 2010 May2011 QX56

HA-4
< PRECAUTION >
PRECAUTIONS
5. When the repair work is completed, re-connect both battery cables. With the brake pedal released, turn
the push-button ignition switch from ACC position to ON position, then to LOCK position. (The steering
wheel will lock when the push-button igniti on switch is turned to LOCK position.)
6. Perform self-diagnosis check of all control units using CONSULT-III.
Precaution for Procedure without Cowl Top CoverINFOID:0000000006276138
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.
Precautions For Refrigerant System ServiceINFOID:0000000006276139
GENERAL REFRIGERANT PRECAUTION
WARNING:
 Never breathe A/C refrigerant an d lubricant vapor or mist. Exposure may irritate eyes, nose and
throat. Use only approved reco very/recycling equipment to discharge HFC-134a (R-134a) refrigerant.
Ventilate work area before resuming service if acci dental system discharge occurs. Additional health
and safety information may be obtained from refrigerant and lubricant manufacturers.
 Never release refrigerant into the air. Use appro ved recovery/recycling recharging equipment to cap-
ture the refrigerant each time an ai r conditioning system is discharged.
 Wear always eye and hand protection (goggles and gloves) when working with any refrigerant or air
conditioning system.
 Never store or heat refrigerant containers above 52 °C (126 °F).
 Never heat a refrigerant container with an open flame; Place the bottom of the container in a warm
pail of water if container warming is required.
 Never intentionally drop, puncture, or incinerate refrigerant containers.
 Keep refrigerant away from open flames: pois onous gas is produced if refrigerant burns.
 Refrigerant displaces oxygen, therefore be certain to work in well ventilated areas to prevent suffo-
cation.
 Never pressure test or leakage test HFC-134a (R- 134a) service equipment and/or vehicle air condi-
tioning systems with compressed air during repair. Some mixtures of air and HFC-134a (R-134a)
have been shown to be combusti ble at elevated pressures. These mixtures, if ignited, may cause
injury or property damage. Additional health and safety information may be obtained from refriger-
ant manufacturers.
WORKING WITH HFC-134a (R-134a)
CAUTION:
 CFC-12 (R-12) refrigerant and HFC-134a (R-134a) re frigerant are not compatible. These regrigerants
must never be mixed, even in the smallest amount s. Compressor malfunction is likely occur if the
refrigerants are mixed.
 Use only specified lubricant for the HFC-134a (R-134a) A/C system and HFC-134a (R-134a) compo-
nents. Compressor malfunction is likely to occur if lubricant other than that specified is used.
 The specified HFC-134a (R-134a) lu bricant rapidly absorbs moisture from the atmosphere. The fol-
lowing handling precauti ons must be observed:
- Cap (seal) immediately the compon ent to minimize the entry of moisture from the atmosphere when
removing refrigerant components from a vehicle.
- Never remove the caps (unseal) until just before co nnecting the components when installing refrig-
erant components to a vehicle. Connect all refr igerant loop components as quickly as possible to
minimize the entry of moisture into system.
- Use only the specified lubricant from a sealed contai ner. Reseal immediately containers of lubricant.
Lubricant becomes moisture saturated and should not be used without proper sealing.
PIIB3706J
Revision: 2010 May2011 QX56

HAC-1
VENTILATION, HEATER & AIR CONDITIONER
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SECTION HAC
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CONTENTS
HEATER & AIR CONDITIONING CONTROL SYSTEM
AUTOMATIC AIR CONDITIONING
PRECAUTION ................ ...............................
5
PRECAUTIONS .............................................. .....5
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
5
SYSTEM DESCRIPTION ..............................6
COMPONENT PARTS ................................... .....6
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ......
6
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Component Parts Location .............................
6
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Component Description ..................................
7
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ......
8
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Component Parts Location .............................
9
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Component Description ................................
10
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ...................................................................... ....
10
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Component Parts Location ..........................
11
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Component Description ...............................
11
Aspirator ..................................................................12
Front Blower Motor ..................................................12
Rear Blower Motor ..................................................13
Refrigerant Pressure Sensor ...................................13
SYSTEM .............................................................14
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ....
14
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : System Diagram ...........................................
14
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : System Description .......................................
14
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Flow Control ............................................
15
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Inlet Control .............................................
16
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Outlet Control ..........................................
17
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Compressor Control ......................................
17
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Door Control ..................................................
18
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Temperature Control .....................................
21
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Fail-safe ........................................................
21
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ....
22
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : System Diagram ...........................................
23
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : System Description .......................................
23
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Flow Control ............................................
24
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Air Outlet Control ..........................................
25
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Door Control ..................................................
26
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Temperature Control .....................................
27
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ....................................................................... ....
27
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : System Diagram ..........................................
28
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : System Description ......................................
28
Revision: 2010 May2011 QX56

HAC-2
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Automatic Intake Control (Exhaust Gas /
Outside Odor Detecting Mechanism) .....................
28
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Plasmacluster Control .................................
29
OPERATION ......................................................30
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
30
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Switch Name and Function ....................... ...
30
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
35
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Switch Name and Function ....................... ...
35
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ....................................................................... ...
37
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Switch Name and Function .........................
37
DIAGNOSIS SYSTEM (HVAC) ..........................39
Description ........................................................... ...39
CONSULT-III Function ...........................................39
ECU DIAGNOSIS INFORMATION ..............42
A/C AUTO AMP. ............................................. ...42
Reference Value .................................................. ...42
Fail-safe ..................................................................45
DTC Index ..............................................................45
ECM, IPDM E/R .................................................47
List of ECU Reference ......................................... ...47
WIRING DIAGRAM .....................................48
AUTOMATIC AIR CONDITIONING SYSTEM ...48
Wiring Diagram .................................................... ...48
BASIC INSPECTION ...................................60
DIAGNOSIS AND REPAIR WORK FLOW ..... ...60
Work Flow ............................................................ ...60
OPERATION INSPECTION ............................ ...62
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
62
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Work Procedure ........................................ ...
62
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
64
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Work Procedure ........................................ ...
64
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ....................................................................... ...
66
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Work Procedure ..........................................
66
SYSTEM SETTING ............................................68
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
68
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Temperature Setting Trimmer (Front) ..........
68
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Foot Position Setting Trimmer ......................
68
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Inlet Port Memory Function (FRE) ................
69
FRONT AUTOMATIC AIR CONDITIONING SYS-
TEM : Inlet Port Memory Function (REC) ...............
69
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM ........................................................................ ...
69
REAR AUTOMATIC AIR CONDITIONING SYS-
TEM : Temperature Setting Trimmer (Rear) ...........
69
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) ....................................................................... ...
70
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Exhaust Gas / Outside Odor Detecting
Sensor Sensitivity Adjustment Function ..................
70
ACCS (ADVANCED CLIMATE CONTROL SYS-
TEM) : Auto Intake Switch Interlocking Movement
Change Function .....................................................
70
DTC/CIRCUIT DIAGNOSIS ........................72
U1000 CAN COMM CIRCUIT ......................... ...72
Description ........................................................... ...72
DTC Logic ...............................................................72
Diagnosis Procedure ...............................................72
U1010 CONTROL UNIT (CAN) .........................73
Description ........................................................... ...73
DTC Logic ...............................................................73
Diagnosis Procedure ...............................................73
B2578, B2579 FRONT IN-VEHICLE SENSOR ...74
DTC Logic ............................................................ ...74
Diagnosis Procedure ...............................................74
Component Inspection ............................................75
B257B, B257C AMBIENT SENSOR .................77
DTC Logic ............................................................ ...77
Diagnosis Procedure ...............................................77
Component Inspection ............................................78
B2581, B2582 INTAKE SENSOR .....................80
DTC Logic ............................................................ ...80
Diagnosis Procedure ...............................................80
Component Inspection ............................................81
B262A, B262B, B2657, B2658 EXHAUST
GAS/OUTSIDE ODOR DETECTING SENSOR
...
83
DTC Logic ............................................................ ...83
Diagnosis Procedure ...............................................83
Revision: 2010 May2011 QX56

HAC-4
FRONT AUTOMATIC AIR CONDITIONING
SYSTEM .......................................................... .
133
Diagnosis Chart By Symptom .............................. ..133
REAR AUTOMATIC AIR CONDITIONING
SYSTEM .......................................................... .
135
Diagnosis Chart By Symptom .............................. ..135
ACCS (ADVANCE CLIMATE CONTROL
SYSTEM) .........................................................
137
Symptom Table ................................................... ..137
INSUFFICIENT COOLING ...............................138
FRONT AIR CONDITIONER .................................. ..138
FRONT AIR CONDITIONER : Description ............138
FRONT AIR CONDITIONER : Diagnosis Proce-
dure .......................................................................
138
REAR AIR CONDITIONER .................................... ..139
REAR AIR CONDITIONER : Description ...............139
REAR AIR CONDITIONER : Diagnosis Procedure
..
139
INSUFFICIENT HEATING .............................. .140
FRONT AIR CONDITIONER .................................. ..140
FRONT AIR CONDITIONER : Description ............140
FRONT AIR CONDITIONER : Diagnosis Proce-
dure .......................................................................
140
REAR AIR CONDITIONER .................................... ..140
REAR AIR CONDITIONER : Description ...............141
REAR AIR CONDITIONER : Diagnosis Procedure
..
141
COMPRESSOR DOSE DOT OPERATE ........ .142
Description ........................................................... ..142
Diagnosis Procedure .............................................142
REMOVAL AND INSTALLATION ..............144
FRONT A/C CONTROL .................................. .144
Removal and Installation ..................................... ..144
REAR A/C CONTROL .....................................145
Removal and Installation ..................................... ..145
A/C AUTO AMP. ..............................................146
Removal and Installation ..................................... ..146
AMBIENT SENSOR ..........................................147
Removal and Installation ...................................... .147
IN-VEHICLE SENSOR ......................................148
FRONT A/C UNIT ASSEMBLY ...............................148
FRONT A/C UNIT ASSEMBLY : Removal and In-
stallation ............................................................... .
148
REAR A/C UNIT ASSEMBLY .................................148
REAR A/C UNIT ASSEMBLY : Removal and In-
stallation ............................................................... .
148
SUNLOAD SENSOR ........................................149
Removal and Installation ...................................... .149
INTAKE SENSOR .............................................150
Exploded View ..................................................... .150
Removal and Installation .......................................150
EXHAUST GAS/OUTSIDE ODOR SENSOR ...151
Removal and Installation ...................................... .151
DOOR MOTOR .................................................152
Exploded View ..................................................... .152
MODE DOOR MOTOR ........................................... .153
MODE DOOR MOTOR : Removal and Installation .153
AIR MIX DOOR MOTOR ........................................ .153
AIR MIX DOOR MOTOR : Removal and Installa-
tion ....................................................................... .
153
INTAKE DOOR MOTOR ........................................ .153
INTAKE DOOR MOTOR : Removal and Installa-
tion ........................................................................
153
UPPER VENTILATOR DOOR MOTOR ..................154
UPPER VENTILATOR DOOR MOTOR : Removal
and Installation ..................................................... .
154
REAR MODE DOOR MOTOR ................................ .154
REAR MODE DOOR MOTOR : Removal and In-
stallation ................................................................
154
REAR AIR MIX DOOR MOTOR ............................. .154
REAR AIR MIX DOOR MOTOR : Removal and In-
stallation ................................................................
154
IONIZER ............................................................155
Exploded View ..................................................... .155
Removal and Installation .......................................155
Revision: 2010 May2011 QX56

PRECAUTIONSHAC-5
< PRECAUTION > [AUTOMATIC AIR CONDITIONING]
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006275847
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 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 whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SRS AIR BAG” and “SEAT BELT” of this
Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision that would result in air ba g 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 “SRS AIR BAG”.
 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 Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the
ignition ON or engine running, DO NOT use air or electric 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.
Revision: 2010 May2011 QX56