2008 INFINITI QX56 Stop light

EXL-20
< FUNCTION DIAGNOSIS >
TRAILER TOW
TRAILER TOW
System DiagramINFOID:0000000006095108
System DescriptionINFOID:0000000006095109
TRAILER TAIL LAMP OPERATION
The trailer tail lamps are controlled by the trailer tow relay 1 located behind the left side of the instrument panel
(IP). With the combination switch in the 1st position, the BCM detects the LIGHTING SWITCH 1ST POSITION
ON. The BCM sends a parking light ON request via the CAN communication lines to the IPDM E/R. The IPDM
E/R then activates the tail lamp relay which activates the trailer tow relay 1 and sends power to the trailer con-
nector.
TRAILER TURN SIGNAL LAMP OPERATION
The trailer turn signal lamps are controlled by the BCM. When the turn signal switch is in the LH or RH position
with the ignition switch ON, the combination switch sends a signal to the BCM. The BCM detects the TURN
RH or TURN LH ON request. The BCM sends a control signal to the respective trailer turn relay which sends
power to the trailer connector.
TRAILER HAZARD LAMP OPERATION
The trailer hazard lamps are controlled by the BCM. W hen the hazard switch is pressed, the BCM detects the
the hazard ON request. The BCM then sends a control si gnal to both trailer turn relays which sends power to
the trailer connector.
TRAILER BRAKE LAMP OPERATION
The trailer brake lamps are controlled by the BCM. When the brake pedal is depressed, the combination meter
receives a stop lamp switch signal from the stop lamp switch. The combination meter then sends the brake
signal to the BCM via the CAN communication lines. The BCM then sends a control signal to both trailer turn
relays which sends power to the trailer connector.
AWLIA1764GB
Revision: March 2010 2008 QX56

TRAILER TOWEXL-21
< FUNCTION DIAGNOSIS >
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Component Parts LocationINFOID:0000000006095110
Component DescriptionINFOID:0000000006095111
1. BCM M18, M19, M20 (view with instru- ment panel removed) 2. IPDM E/R E119, E122, E123, E124 3. Combination meter M23, M24
4. Combination switch M28 5. Trailer tow relay 1 M51 (view with
steering member removed) 6. Battery
7. Trailer turn relay LH E156 8. Trailer turn relay RH E157 9. Trailer tow relay 2 E140
10. Stop lamp switch E38
AWLIA1772ZZ
Part name Description
BCM • Receives lighting and turn signal requests from combination
switch.
• Receives stop lamp signal requests from combination meter via CAN communication.
• Sends lighting signal request to the IPDM E/R to control the tail
lamp relay via CAN communication.
• Sends turn/hazard/brake control signal to the trailer turn relays.
IPDM E/R Activates the tail lamp relay upon request from the BCM via CAN
communication.
Revision: March 2010
2008 QX56

EXL-22
< FUNCTION DIAGNOSIS >
TRAILER TOW
Combination meter• Receives stop lamp switch signal from stop lamp switch.
• Sends stop lamp signal request to the BCM via CAN communi-
cation.
Combination switch Outputs lighting and turn signal requests to the BCM.
Revision: March 2010 2008 QX56

EXL-24
< FUNCTION DIAGNOSIS >
DIAGNOSIS SYSTEM (BCM)
1: The item is indicated, not monitored
ACTIVE TEST
Monitor item[Unit] Description
IGN ON SW
[ON/OFF] The switch status input from ignition switch
ACC ON SW
[ON/OFF] The switch status input from ignition switch
TURN SIGNAL R
[ON/OFF]
Each switch status that BCM judges from the combination switch reading function
TURN SIGNAL L
[ON/OFF]
HI BEAM SW
[ON/OFF]
HEAD LAMP SW1
[ON/OFF]
HEAD LAMP SW2
[ON/OFF]
LIGHT SW 1ST
[ON/OFF]
AUTO LIGHT SW
[ON/OFF]
PASSING SW
[ON/OFF]
FR FOG SW
[ON/OFF]
CARGO LAMP SW
[ON/OFF]
RR FOG SW
1
[ON/OFF]
—
DOOR SW-DR
[ON/OFF] The switch status input from front door switch LH
DOOR SW-AS
[ON/OFF] The switch status input from front door switch RH
DOOR SW-RR
[ON/OFF] The switch status input from rear door switch RH
DOOR SW- RL
[ON/OFF] The switch status input from rear door switch LH
DOOR SW-BK
[ON/OFF] The switch status input from the back door switch
OPTICAL SENSOR
[V] The value of exterior brightness voltage input from the optical sensor
Test item
Operation Description
TA I L L A M P ON
Transmits the position light request signal to IPDM E/R via CAN commu-
nication to turn the tail lamp ON.
OFF Stops the tail lamp request signal transmission.
HEAD LAMP HI
Transmits the high beam request signal via CAN communication to turn
the headlamp (HI)
LO Transmits the low beam request signal via CAN communication to turn
the headlamp (LO).
OFF Stops the high & low beam request signal transmission.
Revision: March 2010 2008 QX56

DIAGNOSIS SYSTEM (BCM)EXL-25
< FUNCTION DIAGNOSIS >
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1: The item is indicated, not monitored.
FLASHER
FLASHER : CONSULT-III Function (BCM - FLASHER)INFOID:0000000001547121
DATA MONITOR
ACTIVE TEST
FR FOG LAMP ON
Transmits the front fog lamp light request signal to IPDM E/R via CAN
communication to turn the front fog lamp ON.
OFF Stops the front fog lamp request signal transmission.
CORNERING LAMP
1
RH —
LH
OFF
CARGO LAMP ON
Tramsmits the cargo lamp request signal to the IPDM E/R via CAN com-
munication to turn on the cargo lamp.
OFF Stops the cargo lamp request signal transmission.
Test item
Operation Description
Monitor item
[Unit] Description
IGN ON SW
[ON/OFF] The switch status input from the ignition switch
HAZARD SW
[ON/OFF] The switch status input from the hazard warning switch
TURN SIGNAL R
[ON/OFF] Each switch condition that BCM judges from the combination switch reading function
TURN SIGNAL L
[ON/OFF]
BRAKE SW
[ON/OFF] The switch status input from the brake switch
Test item
Operation Description
FLASHER RH Blinks right turn signal lamp.
LH Blinks left turn signal lamp.
OFF Turns turn signal lamps (right and left) OFF.
Revision: March 2010 2008 QX56

EXT-6
< SERVICE INFORMATION >
SQUEAK AND RATTLE TROUBLE DIAGNOSES
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-clutch on M/T model, drive position on A/T model).
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 v ehicle slowly on an undulating or rough road to stress the
vehicle body.
CHECK RELATED SERVICE BULLETINS
After verifying the customer concern or symptom, chec k ASIST for Technical Service Bulletins (TSBs) related
to that concern or symptom.
If a TSB relates to the symptom, follo w 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: J-39565 and mechanic's 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 fasteners 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 the 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 EXT-7, "
Generic Squeak and Rattle Troubleshooting".
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 loos ening and retightening the component, if possible.
- insulate components with a suitable insulator such as urethane pads, foam blocks, felt cloth tape or urethane tape. A NISSAN Squeak and Rattle Kit (J-43980) is av ailable through your authorized NISSAN Parts Depart-
ment.
CAUTION:
Do not use excessive force as many components are constructed of plastic and may be damaged.
Always check with the Parts Department for the latest parts information.
The following materials are contained in the NISSAN 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 ×1.97 in)
FELT CLOTH TAPE
Used to insulate where movemen t 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
Insulates where slight movement is present. Ideal for inst rument panel applications.
Revision: March 2010 2008 QX56

EXT-8
< SERVICE INFORMATION >
SQUEAK AND RATTLE TROUBLE DIAGNOSES
Most of these incidents can be repaired by adjusting, securing or insulating the item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINING
Noises in the sunroof/headlining area c an often be traced to one of the following:
1. Sunroof lid, rail, linkage or seals making a rattle or light knocking noise
2. Sun visor shaft shaking in the holder
3. Front or rear windshield touching headliner and squeaking
Again, pressing on the components to stop the noise while duplicating the conditions can isolate most of these
incidents. Repairs usually consist of insulating with felt cloth tape.
OVERHEAD CONSOLE (FRONT AND REAR)
Overhead console noises are often caused by the c onsole panel clips not being engaged correctly. Most of
these incidents are repaired by pushing up on the c onsole at the clip locations until the clips engage.
In addition look for:
1. Loose harness or harness connectors.
2. Front console map/reading lamp lens loose.
3. Loose screws at console attachment points.
SEATS
When isolating seat noise it's important to note the pos ition the seat is in and the load placed on the seat when
the noise is present. These conditions should be duplicated 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 suspected components while duplicating the con-
ditions under which the noise occurs. Most of thes e incidents can be repaired by repositioning the component
or applying urethane tape to the contact area.
UNDERHOOD
Some interior noise may be caused by components under the hood or on the engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noise include:
1. Any component installed to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator installation 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 can usually be made by moving, adjusting, securing, or
insulating the component causing the noise.
Revision: March 2010 2008 QX56

HA-24
< ON-VEHICLE MAINTENANCE >
FLUORESCENT LEAK DETECTOR
FLUORESCENT LEAK DETECTOR
Checking of Refrigerant LeaksINFOID:0000000001516646
PRELIMINARY CHECK
Perform a visual inspection of all refrigeration parts, fittings, hoses and components for signs of A/C oil leak-
age, damage, and corrosion. Any A/C oil leakage may indicate an area of refrigerant leakage. Allow extra
inspection time in these areas when using either an el ectronic refrigerant leak detector (J-41995) or fluores-
cent dye leak detector (J-42220).
If any dye is observed using a fluorescent dye leak detector (J-42220), confirm the leak using a electronic
refrigerant leak detector (J-41995). It is possible that the dye is from a prior leak that was repaired and not
properly cleaned.
When searching for leaks, do not stop when one leak is found but continue to check for additional leaks at all
system components and connections.
When searching for refrigerant leaks using an electronic refrigerant leak detector (J-41995), move the probe
along the suspected leak area at 25 - 50 mm (1 - 2 in) per second and no further than 6 mm (1/4 in) from the
component.
CAUTION:
Moving the electronic refrigerant l eak detector probe slower and closer to the suspected leak area will
improve the chances of finding a leak.
Checking System for L eaks Using the Fluorescent Dye Leak DetectorINFOID:0000000001516647
1. Check the A/C system for leaks using the fluorescent dye leak detector and safety goggles (J-42220) in a
low sunlight area (area without windows preferable). Il luminate all components, fittings and lines. The dye
will appear as a bright green/yellow area at the point of leakage. Fluorescent dye observed at the evapo-
rator drain opening indicates an evaporator core asse mbly leak (tubes, core or expansion valve).
2. If the suspected area is difficult to see, use an adjustable mirror or wipe the area with a clean shop rag or cloth, then inspect the shop rag or cloth with the fl uorescent dye leak detector (J-42220) for dye residue.
3. After the leak is repaired, remove any residual dye using refrigerant dye cleaner (J-43872) to prevent
future misdiagnosis.
4. Perform a system performance check and then verify t he leak repair using a electronic refrigerant leak
detector (J-41995).
NOTE:
• Other gases in the work area or substances on the A/C components, for example, anti-freeze, wind-
shield washer fluid, solvents and oils, may falsely tri gger the leak detector. Make sure the surfaces to be
checked are clean.
• Clean with a dry cloth or blow off with shop air.
• Do not allow the sensor tip of the electronic refri gerant leak detector (J-41995) to contact with any sub-
stance. This can also cause false readings and may damage the detector.
Dye InjectionINFOID:0000000001516648
NOTE:
This procedure is only necessary when recharging the system or when the compressor has seized and must
be replaced.
1. Check the A/C system static (at rest) pressure . Pressure must be at least 345 kPa (3.52 kg/cm
2 , 50 psi).
2. Pour one bottle 7.4 cc (1/4 ounce) of the HFC-134a (R -134a) fluorescent leak detection dye (J-41447) into
the HFC-134a (R-134a) dye injector (J-41459).
CAUTION:
If repairing the A/C system or replacing a co mponent, pour the HFC-134a (R-134a) fluorescent leak
detection dye (J-41447) directly into the open system connection and proceed with the service
procedures.
3. Connect the refrigerant dye injector (J-41459) to the low-pressure service valve.
4. Start the engine and switch the A/C system ON.
5. When the A/C system is operating (compressor running), inject one bottle 7.4 cc (1/4 ounce) of HFC-134a (R-134a) fluorescent leak detection dye (J-41447) through the low-pressure service valve using HFC-
134a (R-134a) dye injector (J-41459). Refer to the manufacturer's operating instructions.
Revision: March 2010 2008 QX56