air condition INFINITI QX56 2011 Factory Service Manual

MA-28
< PERIODIC MAINTENANCE >
CHASSIS MAINTENANCE
BRAKE FLUID LEVEL AND LEAKS : Inspection
INFOID:0000000006220939
 Check that the fluid level in the sub tank is within the specified range (MAX – MIN lines).
CAUTION:
Turn OFF the ignition switch an d depress the brake pedal 20 times or more to check brake fluid level.
NOTE:
Since brake fluid is in the accumulator in pressurized condition, the reservoir tank brake fluid level should be
lower than the MAX line.
 Visually check for any brake fluid leakage around the reservoir tank.
 Check the brake system for any leakage if the fl uid level is extremely low (lower than MIN).
 Check the brake system for fluid leakage if the warn ing lamp remains illuminated even after the parking
brake is released.
 Check the sub tank for the mixing of foreign ma tter (e.g. dust) and oils other than brake fluid.
BRAKE LINES AND CABLES
BRAKE LINES AND CABLES : InspectionINFOID:0000000006220940
1. Check brake line (tubes and hoses) for cracks, deterioration or other damage. Replace any damaged
parts.
2. Depress the brake pedal with a force of 490 N (50 kg, 110lb) and hold down the pedal for approx. 5 seconds with the engine run-
ning. Check for any fluid leakage.
CAUTION:
Retighten the applicable conn ection to the specified torque
and repair any abnormal (damag ed, worn or deformed) part
if any brake fluid leakage is present).
BRAKE FLUID
BRAKE FLUID : Bleeding Brake SystemINFOID:0000000006220941
CAUTION:
 Bleed air in the following order: motor/accumulator assembly → front right brake → front left brake
→ rear left brake → and rear right brake.
 The VDC warning lamp, ABS warning lamp and br ake warning lamp turn ON and DTC “C118E” may
be detected in self-diagnosis r esult for “ABS” with CONSULT-II I when the brake pedal is excessively
operated, such as air bleeding. Thi s is not a system malfunction becau se this occurs due to the tem-
porary decrease in accumulator fl uid pressure. The system returns to normal condition when the
accumulator fluid pressure reaches the specified pressu re with the ignition switch ON and the VDC
warning lamp, ABS warning lamp, and brake warnin g lamp turn OFF. After these steps, erase self-
diagnosis results for “ABS” with CONSULT-III.
- DTC other than “C118E” is detected: Refer to BRC-51, "
DTC Index".
NOTE:
When the ignition switch is ON, the brake warning la mp may turns ON even when the parking brake pedal is
released with the brake fluid within the specified level. This indicates the decrease in accumulator fluid pres-
sure.
MOTOR/ACCUMULATOR ASSEMBLY
CAUTION:
 If the brake fluid adheres to the brake caliper assembly and disc rotor, quickly wipe it off.
 Never spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never operate the brake pedal with the reservoir cap removed. Failure to do this may cause the scat-
tering of brake fluid.
 Never operate the brake pedal excessively during the work procedure.
 Monitor the fluid level in the reservoir tank while performing the air bleeding.
SBR389C
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MA-30
< PERIODIC MAINTENANCE >
CHASSIS MAINTENANCE
 Never operate the brake pedal excessively during the work procedure.
 Monitor the fluid level in the reservoir tank while performing the air bleeding.
 Bleed air in the following order: motor/accumulator assembly → front right brake → front left brake
→ rear left brake → and rear right brake.
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more. NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Check that there is no foreign material in the reservoir tank, and refill with new brake fluid. CAUTION:
 Never reuse drained brake fluid.
 Never allow oils other than brake fluid to enter the reservoir tank.
4. Turn the ignition switch ON.
5. Connect a vinyl tube to the bleed valve.
6. Depress the brake pedal and loosen the bleeder valve.
7. Depress and hold the brake pedal depression to dischar ge 100 cc of brake fluid before tightening the air
bleeder to the specified torque. Refer to BR-42, "
BRAKE CALIPER ASSEMBLY : Exploded View".
NOTE:
Since brake fluid is conveyed by the motor, the brake pedal is not necessarily depressed.
8. Release the brake pedal.
9. Repeat steps 1 to 8 until all of the air is out of the brake line and tighten the air bleeder to the specified
torque with the brake pedal depressed. Refer to BR-42, "
BRAKE CALIPER ASSEMBLY : Exploded View".
10. Check that no drag feel is present for the rear disc brake. Refer to BR-45, "
BRAKE CALIPER ASSEMBLY
: Inspection".
11. Check each item of brake pedal. Adjust it if t he measurement value is not the standard. Refer to BR-7,
"Inspection and Adjustment".
BRAKE FLUID LEVEL ADJUSTMENT AFTER AIR BLEEDING
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more.
NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Adjust brake fluid level to the reservoir tank MAX line. CAUTION:
Never adjust with the ignition switch ON.
4. Turn the ignition switch ON.
5. Check that the reservoir tank brake fluid level is 4 − 12 mm (0.16
− 0.47 in) lower than the MAX line.
NOTE:
Since brake fluid is in the accumulator in pressurized condition,
the reservoir tank brake fluid level should be lower than the MAX
line.
DISC BRAKE
DISC BRAKE : InspectionINFOID:0000000006220942
DISC ROTOR
Check condition, wear, and damage.
CALIPER
 Check for leakage.
JPFIA0769ZZ
Revision: 2010 May2011 QX56

DIAGNOSIS AND REPAIR WORKFLOWMIR-21
< BASIC INSPECTION >
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BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Work FlowINFOID:0000000006257228
DETAILED FLOW
1.OBTAIN INFORMATION ABOUT SYMPTOM
Interview the customer to obtain the malfunction information (conditions and environment when the malfunc-
tion occurred) as much as possible when the customer brings the vehicle in.
>> GO TO 2.
2.CHECK DTC
Perform self-diagnosis for automatic dr ive positioner (ADP) with CONSULT-III.
Is any DTC detected?
YES >> Refer to ADP-31, "DTCIndex"
NO >> GO TO 3.
3.REPRODUCE THE MALFUNCTION INFORMATION
Check the malfunction on the vehicl e that the customer describes.
Inspect the relation of the symptoms and the condition when the symptoms occur.
>> GO TO 4.
4.IDENTIFY THE MALFUNCTIONING SYST EM WITH “SYMPTOM DIAGNOSIS”
Use “Symptom diagnosis” from the sympt om inspection result in step 3. Then identify where to start perform-
ing the diagnosis based on possible causes and symptoms.
>> GO TO 5.
5.IDENTIFY MALFUNCTIONING PART S WITH “COMPONENT DIAGNOSIS”
Perform the diagnosis with “Component di agnosis” of the applicable system.
>> GO TO 6.
6.REPAIR OR REPLACE THE MALFUNCTIONING PARTS
Repair or replace the specified malfunctioning parts.
>> GO TO 7.
7.FINAL CHECK
Check that malfunctions are not reproduced when obtai ning the malfunction information from the customer,
referring to the symptom inspection result in step 3.
Are all malfunctions corrected?
YES >> INSPECTION END
NO >> GO TO 4.
Revision: 2010 May2011 QX56

MIR-24
< SYMPTOM DIAGNOSIS >
SQUEAK AND RATTLE TROUBLE DIAGNOSES
SQUEAK AND RATTLE TROUBLE DIAGNOSES
Work FlowINFOID:0000000006257247
CUSTOMER INTERVIEW
Interview the customer if possible, to determine the c onditions that exist when the noise occurs. Use the Diag-
nostic Worksheet during the interview to document t he facts and conditions when the noise occurs and any of
customer's comments; refer to MIR-28, "
Diagnostic Worksheet". This information is necessary to duplicate the
conditions that exist when the noise occurs.
 The customer may not be able to provide a detailed description or the location of the noise. Attempt to obtain all the facts and conditions that exist w hen the noise occurs (or does not occur).
 If there is more than one noise in the vehicle, perform a diagnosis and repair the noise that the customer is
concerned about. This can be accomplished by performing a cruise test on the vehicle with the customer.
 After identifying the type of noise, isolate the noise in terms of its characteristics. The noise characteristics
are provided so the customer, service adviser and technician are all speaking the same language when
defining the noise.
 Squeak – (Like tennis shoes on a clean floor)
Squeak characteristics include the light contact/fast movement/brought on by road conditions/hard surfaces
= higher pitch noise/softer surfaces = lower pitch noises/edge to surface = chirping
 Creak – (Like walking on an old wooden floor)
Creak characteristics include firm contact/slow mo vement/twisting with a rotational movement/pitch depen-
dent on materials/often brought on by activity.
 Rattle – (Like shaking a baby rattle)
Rattle characteristics include the fast repeated contac t/vibration or similar movement/loose parts/missing
clip or fastener/incorrect clearance.
 Knock – (Like a knock on a door)
Knock characteristics include hollow sounding/someti mes repeating/often brought on by driver action.
 Tick – (Like a clock second hand) Tick characteristics include gentle contacting of light materials/loose components/can be caused by driver
action or road conditions.
 Thump – (Heavy, muffled knock noise) Thump characteristics include softer k nock/dead sound often brought on by activity.
 Buzz – (Like a bumblebee)
Buzz characteristics include hi gh frequency rattle/firm contact.
 Often the degree of acceptable noise level will vary depending up on the person. A noise that you may judge as acceptable may be very irritating to the customer.
 Weather conditions, especially humidity and temperat ure, may have a great effect on noise level.
DUPLICATE THE NOISE AND TEST DRIVE
If possible, drive the vehicle with the customer until the noise is duplicated. Note any additional information on
the Diagnostic Worksheet regarding the conditions or lo cation of the noise. This information can be used to
duplicate the same conditions when you confirm the repair.
SBT842
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SQUEAK AND RATTLE TROUBLE DIAGNOSESMIR-25
< SYMPTOM DIAGNOSIS >
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If the noise can be duplicated easily during the test drive, to help identify the source of the noise, try to dupli-
cate the noise with the vehicle stopped by doing one or all of the following:
1) Close a door.
2) Tap or push/pull around the area where the noise appears to be coming from.
3) Rev the engine.
4) Use a floor jack to recreate vehicle “twist”.
5) At idle, apply engine load (electrical load, half-cl utch on M/T models, drive position on A/T models).
6) Raise the vehicle on a hoist and hit a tire with a rubber hammer.
 Drive the vehicle and attempt to duplicate the conditions the customer states exist when the noise occurs.
 If it is difficult to duplicate the noise, drive the vehicle slowly on an undulating or rough road to stress the vehicle body.
CHECK RELATED SERVICE BULLETINS
After verifying the customer concern or symptom, che ck ASIST for Technical Service Bulletins (TSBs) related
to that concern or symptom.
If a TSB relates to the symptom, follow the procedure to repair the noise.
LOCATE THE NOISE AND IDENTIFY THE ROOT CAUSE
1. Narrow down the noise to a general area. To help pinpoint the source of the noise, use a listening tool
(Chassis Ear: J-39570, Engine Ear and mechanics stethoscope).
2. Narrow down the noise to a more specific area and identify the cause of the noise by:
 Removing the components in the area that you suspect the noise is coming from.
Do not use too much force when removing clips and fasteners, otherwise clips and fastener can be broken
or lost during the repair, resulting in the creation of new noise.
 Tapping or pushing/pulling the component that you suspect is causing the noise.
Do not tap or push/pull the component with excessive force, otherwise the noise will be eliminated only tem-
porarily.
 Feeling for a vibration with your hand by touching t he component(s) that you suspect is (are) causing the
noise.
 Placing a piece of paper between components that you suspect are causing the noise.
 Looking for loose components and contact marks. Refer to MIR-26, "
Inspection Procedure".
REPAIR THE CAUSE
 If the cause is a loose component, tighten the component securely.
 If the cause is insufficient clearance between components:
- Separate components by repositioning or loosening and retightening the component, if possible.
- Insulate components with a suitable insulator such as urethane pads, foam blocks, felt cloth tape or ure-
thane tape. A Nissan Squeak and Rattle Kit (J-43980) is available through your authorized Nissan Parts
Department.
CAUTION:
Do not use excessive force as many components are constructed of plastic and may be damaged.
NOTE:
Always check with the Parts Department for the latest parts information.
The following materials are contained in the Niss an Squeak and Rattle Kit (J-43980). Each item can be
ordered separately as needed.
URETHANE PADS [1.5 mm (0.059 in) thick]
Insulates connectors, harness, etc.
76268-9E005: 100 ×135 mm (3.94 ×5.31 in)/76884-71L01: 60 ×85 mm (2.36 ×3.35 in)/76884-
71L02:15 ×25 mm (0.59 ×0.98 in)
INSULATOR (Foam blocks)
Insulates components from contact. Can be used to fill space behind a panel.
73982-9E000: 45 mm (1.77 in) thick, 50 ×50 mm (1.97 ×1.97 in)/73982-
50Y00: 10 mm (0.39 in) thick, 50 ×50 mm (1.97 ×1.97 in)
INSULATOR (Light foam block)
80845-71L00: 30 mm (1.18 in) thick, 30 ×50 mm (1.18 ×1.97in)
FELT CLOTHTAPE
Used to insulate where movement does not occur. Ideal for instrument panel applications.
68370-4B000: 15 ×25 mm (0.59 ×0.98 in) pad/68239-13E00: 5 mm (0.20 in) wide tape roll
The following materials, not found in the kit, can also be used to repair squeaks and rattles.
UHMW (TEFLON) TAPE
Revision: 2010 May2011 QX56

MIR-26
< SYMPTOM DIAGNOSIS >
SQUEAK AND RATTLE TROUBLE DIAGNOSES
Insulates where slight movement is present. Ideal for instrument panel applications.
SILICONE GREASE
Used in place of UHMW tape that will be visible or not fit. Will only last a few months.
SILICONE SPRAY
Use when grease cannot be applied.
DUCT TAPE
Use to eliminate movement.
CONFIRM THE REPAIR
Confirm that the cause of a noise is repaired by test driving the vehicle. Operate the vehicle under the same
conditions as when the noise originally occurred. Refer to the notes on the Diagnostic Worksheet.
Inspection ProcedureINFOID:0000000006257248
Refer to Table of Contents for specific component removal and installationinformation.
INSTRUMENT PANEL
Most incidents are caused by contact and movement between:
1. The cluster lid A and instrument panel
2. Acrylic lens and combination meter housing
3. Instrument panel to front pillar garnish
4. Instrument panel to windshield
5. Instrument panel mounting pins
6. Wiring harnesses behind the combination meter
7. A/C defroster duct and duct joint
These incidents can usually be located by tapping or moving the components to duplicate the noise or by
pressing on the components while driving to stop the noise. Most of these incidents can be repaired by
applying felt cloth tape or silicon spray (in hard to reach areas). Urethane pads can be used to insulate
wiring harness.
CAUTION:
Do not use silicone spray to is olate a squeak or rattle. If you saturatethe area with silicone, you
will not be able to recheck the repair.
CENTER CONSOLE
Components to pay attention to include:
1. Shifter assembly cover to finisher
2. A/C control unit and cluster lid C
3. Wiring harnesses behind audio and A/C control unit
The instrument panel repair and isolation pr ocedures also apply to thecenter console.
DOORS
Pay attention to the:
1. Finisher and inner panel making a slapping noise
2. Inside handle escutcheon to door finisher
3. Wiring harnesses tapping
4. Door striker out of alignment causing a popping noise on startsand stops
Tapping or moving the components or pressing on them wh ile driving to duplicate the conditions can isolate
many of these incidents. You can usually insulate the areas with felt cloth tape or insulator foam blocks from
the Nissan Squeak and Rattle Kit (J-43980) to repair the noise.
TRUNK
Trunk noises are often caused by a loose jack or loose items put intothe trunk by the owner.
In addition look for:
1. Trunk lid dumpers out of adjustment
2. Trunk lid striker out of adjustment
3. The trunk lid torsion bars knocking together
4. A loose license plate or bracket
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SQUEAK AND RATTLE TROUBLE DIAGNOSESMIR-27
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Most of these incidents can be repaired by adjusting, securing or insulatingthe item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINING
Noises in the sunroof/headlining area can often be traced to one of the following:
1. Sunroof lid, rail, linkage or seals making a rattle or light knockingnoise
2. Sunvisor shaft shaking in the holder
3. Front or rear windshield touching headlining and squeaking
Again, pressing on the components to stop the noise whil e duplicatingthe conditions can isolate most of these
incidents. Repairs usually consistof insulating with felt cloth tape.
SEATS
When isolating seat noise it's important to note the pos ition the seatis in and the load placed on the seat when
the noise is present. These conditionsshould be duplic ated when verifying and isolating the cause of the
noise.
Cause of seat noise include:
1. Headrest rods and holder
2. A squeak between the seat pad cushion and frame
3. The rear seatback lock and bracket
These noises can be isolated by moving or pressing on the suspectedcomponents while duplicating the condi-
tions under which the noise occurs. Most of these incidents can be repaired by repositioning the component
orapplying urethane tape to the contact area.
UNDERHOOD
Some interior noise may be caused by components under the hood or onthe engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noise include:
1. Any component mounted to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator mounting pins
5. Hood bumpers out of adjustment
6. Hood striker out of adjustment
These noises can be difficult to isolate since they cannot be reached from the interior of the vehicle. The best
method is to secure, move or insulate one component at a time and test drive the vehicle. Also, engine RPM
or load can be changed to isolate the noise. Repairs c an usually be made by moving, adjusting, securing, or
insulating the component causing the noise.
Revision: 2010 May2011 QX56

MWI-6
< SYSTEM DESCRIPTION >
COMPONENT PARTS
SYSTEM DESCRIPTION
COMPONENT PARTS
METER SYSTEM
METER SYSTEM : Component Parts LocationINFOID:0000000006221690
1.IPDM E/R
Refer to
PCS-4, "Component Parts
Location". 2.
ECM
Refer to
EC-16, "
Component Parts
Location". 3. Washer level switch
4. Oil pressure switch
Refer to
EM-57, "
Exploded View".5. Ambient sensor 6. A/C auto amp.
Refer to
HAC-6, "
FRONT AUTO-
MATIC AIR CONDITIONING SYS-
TEM : Component Parts Location".
7. TCM
Refer to
TM-10, "
A/T CONTROL
SYSTEM : Componen t Parts Loca-
tion". 8.ABS actuator and electric unit (con-
trol unit)
Refer to
BRC-10, "
Component Parts
Location". 9.BCM
Refer to
BCS-4, "
BODY CONTROL
SYSTEM : Component Parts Loca-
tion".
10. Fuel level sensor unit 11. Trip computer switch 12. Combination meter
13. Trip reset and illumination control
switch 14. Parking brake switch
A. Under of left side second seat
JSNIA3157ZZ
Revision: 2010 May2011 QX56

MWI-22
< SYSTEM DESCRIPTION >
SYSTEM
The combination meter measures and displays travel time (ignition switch ON time).
Travel Distance
The combination meter calculates mileage, based on the following signals and displays the mileage on the
information display.
Ambient Temperature
 The combination meter corrects an indicated temperature, based on various signals.
 The combination meter calculates ambient air temperature based on the following signals, and the calcu-
lated value is displayed on the information display.
Correction Process (Temperature indicated soon after the ignition switch ON) A temperature indicated soon after the ignition switch is turned ON depends on the time from the ignition switch OFF to ON and a temperatur e detected by the ambient sensor.
When any condition described below is met, an ambient sensor-detected temperature is indicated.- Time from the ignition switch OFF to ON ≥ Predetermined time
- Sensor-detected temperature < Temperat ure at the last ignition switch OFF
Correction Process (Temperature at the Ignition switch ON) A temperature indicated when the ignition switch is ON depends on a vehicle speed, an ambient sensor-
detected temperature, and traveling time.
The temperature on the information display is corrected to an am bient sensor-detected temperature when the following condition
is met.
- Ambient sensor-detected temperature < Temperature on the information display
A temperature on the information display is no t updated when the following condition is met.
- Ambient sensor-detected temperature ≥ Temperature on the information display
- Vehicle speed ≤ 20 km/h (12 MPH)
A temperature on the information display slowly rises to an ambient sensor-detected temperature when the following condition is
met.
- Ambient sensor-detected temperature ≥ Temperature on the information display
- Vehicle speed ≥ 20 km/h (12 MPH)
A temperature on the information display rapidly rises to an ambient sensor-detected temperature when the following condition
is met.
- Ambient sensor-detected temperature ≥ Temperature on the information display
- Vehicle speed ≥ 20 km/h (12 MPH)
- When driving more than set time
A/C auto amp. connection recognition
 The combination meter judges the A/C auto amp. connection/disconnection, based on an A/C auto amp.
connection recognition signal to judge the presence/ absence of the ambient sensor power output.
NOTE:
 After an ignition switch is turned ON, “–––” is displayed until after a 2.5 seconds.
Signal name Signal path
Ignition signal —
Vehicle speed signal ABS actuator and electric unit (control unit) Combination meter
Signal name Signal path
Ignition signal —
Ambient sensor signal Ambient sensor Combination meter
A/C auto amp. connection recognition signal A/C auto amp. Combination meter
Vehicle speed signal ABS actuator and electric unit (control unit) Combination meter
Revision: 2010 May2011 QX56

MWI-36
< ECU DIAGNOSIS INFORMATION >
COMBINATION METER
LIGHT INDIgnition switch
ONTail lamp indicator lamp ON On
Tail lamp indicator lamp OFF Off
OIL W/L Ignition switch
ONOil pressure warning lamp ON On
Oil pressure warning lamp OFF Off
MIL Ignition switch
ONMalfunction indicator lamp ON On
Malfunction indicator lamp OFF Off
GLOW IND Ignition switch
ONNOTE:
This item is displayed, but cannot be moni-
tored.
Off
CRUISE IND Ignition switch
ONCRUISE indicator ON On
CRUISE indicator OFF Off
SET IND Ignition switch
ONSET indicator ON On
SET indicator OFF Off
CRUISE W/L Ignition switch
ONCRUISE warning lamp ON On
CRUISE warning lamp OFF Off
BA W/L Ignition switch
ONIBA OFF indicator lamp ON On
IBA OFF indicator lamp OFF Off
ATC/T-AMT W/L Ignition switch
ONA/T check warning lamp ON On
A/T check warning lamp OFF Off
ATF TEMP W/L Ignition switch
ONNOTE:
This item is displayed, but cannot be moni-
tored.
Off
4WD W/L Ignition switch
ON4WD warning lamp ON On
4WD warning lamp OFF Off
FUEL W/L Ignition switch
ONDuring low fuel warning indication On
Other than the above Off
WASHER W/L Ignition switch
ONDuring low washer flui
d warning indication On
Other than the above Off
AIR PRES W/L Ignition switch
ONLow tire pressure
warning lamp ON On
Low tire pressure warning lamp OFF Off
KEY G/Y W/L Ignition switch
ONKEY warning lamp (Green/Yellow) ON On
KEY warning lamp (Green/Yellow) OFF Off
KEY KNOB W/L Ignition switch
ONNOTE:
This item is displayed, but cannot be moni-
tored.
Off
AFS OFF IND Ignition switch
ONAFS OFF indicator lamp ON On
AFS OFF indicator lamp OFF Off
DDS W/L Ignition switch
ONNOTE:
This item is displayed, but cannot be moni-
tored.
Off
LANE W/L
Ignition switch
ONLane departure warning lamp ON On
Lane departure warning lamp OFF Off
LDP IND Ignition switch
ONLDP ON indicator lamp ON On
LDP ON indicator lamp OFF Off
AT P W / L Ignition switch
ONATP warning lamp ON On
ATP warning lamp OFF Off
Monitor Item Condition Value/Status
Revision: 2010 May2011 QX56