EXTERIOR LIGHTING SYSTEM SYMPTOMSEXL-137
< SYMPTOM DIAGNOSIS >
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Daytime light system does not activate. • Either high beam bulb
• Parking brake switch
• Combination switch (lighting
and turn signal switch)
•BCM
• IPDM E/R
• Daytime light relay
• Harness between IPDM E/R
and daytime light relay. Daytime light system description.
Refer to
EXL-9, "System Descrip-
tion".
Front fog lamp is not
turned ON. One side
• Front fog lamp bulb
• Harness between IPDM E/R
and the front combination lamp
• Front combination lamp
• IPDM E/R Front fog lamp circuit
Refer to
EXL-36
.
Both sides Symptom diagnosis
"BOTH SIDE FRONT FOG LAMPS ARE NOT TURNED ON"
Refer to EXL-142
.
Parking lamp is not turned
ON. One side•Fuse
• Parking lamp bulb
• Harness between IPDM E/R
and the front/rear combination
lamp
• Front/rear combination lamp
• IPDM E/R Parking lamp circuit
Refer to
EXL-38
.
Both sides Symptom diagnosis
"PARKING, LICENSE PLATE AND TAIL LAMPS ARE NOT TURNED
ON"
Refer to EXL-141
.
Turn signal lamp does not
blink. Indicator lamp is nor-
mal.
(The applicable side
performs the high flash-
er activation).• Harness between BCM and
each turn signal lamp
• Turn signal lamp bulb
• Door mirror Turn signal lamp circuit
Refer to
EXL-44
.
Turn signal indicator lamp
does not blink. One side
Combination meter —
Both sides
(Always) • Turn signal indicator lamp sig-
nal
• Combination meter
•BCM • Combination meter.
Data monitor "TURN IND".
• BCM (FLASHER) Active test "FLASHER".
Both sides
(Does blink when acti-
vating the hazard warn-
ing lamp with the
ignition switch OFF) • The combination meter power
supply and the ground circuit
• Combination meter Combination meter
Power supply and the ground circuit
Refer to
MWI-28
.
Symptom
Possible causeInspection item
Revision: April 20092010 QX56
PARKING, LICENSE PLATE AND TAIL LAMPS ARE NOT TURNED ON
EXL-141
< SYMPTOM DIAGNOSIS >
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PARKING, LICENSE PLATE AND TA IL LAMPS ARE NOT TURNED ON
DescriptionINFOID:0000000005146692
The parking, license plate and tail lamps do not turn ON in with any combination switch (lighting and turn sig-
nal switch) setting.
Diagnosis ProcedureINFOID:0000000005146693
1.COMBINATION SWITCH (LIGHTING AND TURN SIGNAL SWITCH) INSPECTION
Check the combination switch (lighting and turn signal switch). Refer to BCS-38, "
Diagnosis Procedure".
Is the combination switch (lighting and turn signal switch) normal?
YES >> GO TO 2.
NO >> Repair or replace the malfunctioning part.
2.CHECK TAIL LAMP RELAY REQUEST SIGNAL INPUT
CONSULT-III DATA MONITOR
1. Select "TAIL & CLR REQ" of IPDM E/R DATA MONITOR item.
2. With operating the combination switch (lighting and turn signal switch), check the monitor status.
Is the item status normal?
YES >> GO TO 3.
NO >> Replace BCM. Refer to BCS-59, "
Removal and Installation".
3.PARK LAMP CIRCUIT INSPECTION
Check the parking lamp circuit. Refer to EXL-38, "
Description".
Is the tail lamp circuit normal?
YES >> Replace IPDM E/R. Refer to PCS-35, "Removal and Installation of IPDM E/R".
NO >> Repair or replace the malfunctioning part.
Monitor item ConditionMonitor status
TAIL & CLR
REQ combination switch (lighting
and turn signal switch) 1ST
ON
OFF OFF
Revision: April 20092010 QX56
HOW TO READ WIRING DIAGRAMSGI-11
< HOW TO USE THIS MANUAL >
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DescriptionINFOID:0000000005149578
SWITCH POSITIONS
Switches are shown in wiring diagrams as if the vehicle is in the “normal” condition.
A vehicle is in the “normal” condition when:
Number Item Description
1 Power supply • This means the power supply of fusible link or fuse.
2 Fusible link • “X” means the fusible link.
3 Number of fusible link/
fuse • This means the number of fusible link or fuse location.
4 Fuse • “/” means the fuse.
5 Current rating of fus-
ible link/fuse • This means the current rating of the fusible link or fuse.
6 Optional splice • The open circle shows that the splice is optional depending on vehicle application.
7 Connector number • The letter shows which harness the connector is located in.
• Example “M”: main harness. For detail and to locate the connector, refer to
PG-61, "
Elec-
trical Units Location", PG-41, "Harness Layout".
8Splice • The shaded circle “ ” means the splice.
9 Page crossing • This circuit continues to an adjacent page.
10 Option abbreviation • This means the vehicle specifications which layouts the circuit between “ ”.
11 Relay • This shows an internal representation of the relay.
12 Option description • This shows a description of the option abbreviation used on the page.
13 Switch • This shows that continuity exists between terminals 1 and 2 when the switch is in the A
position. Continuity exists between terminals 1 and 3 when the switch is in the B position.
14 Circuit (Wiring) • This means the wiring.
15 System branch • This shows that the circuit is branched to other systems.
16 Shielded line • The line enclosed by broken line circle shows shield wire.
17 Component name • This shows the name of a component.
18 Ground (GND) • This shows the ground connection.
19 Connector • This means the connector information.
• This unit-side is described by the connector symbols.
20 Connectors • This means that a transmission line bypasses two connectors or more.
21 Wire color • This shows a code for the color of the wire.
B = Black
W = White
R = Red
G = Green
L = Blue
Y = Yellow
LG = Light Green BR = Brown
OR or O = Orange
P = Pink
PU or V (Violet) = Purple
GY or GR = Gray
SB = Sky Blue
CH = Dark Brown
DG = Dark Green
• When the wire color is striped, the base color is given first, followed by the stripe color as shown below:
Example: L/W = Blue with White Stripe
22 Terminal number • This means the terminal number of a connector.
Revision: April 20092010 QX56
SERVICE INFORMATION FOR ELECTRICAL INCIDENTGI-39
< BASIC INSPECTION >
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lowing section illustrates ways to simulate the c onditions/environment under which the owner experiences an
electrical incident.
The section is broken into the six following topics:• Vehicle vibration
• Heat sensitive
• Freezing
• Water intrusion
• Electrical load
• Cold or hot start up
Get a thorough description of the incident from the customer . It is important for simulating the conditions of the
problem.
VEHICLE VIBRATION
The problem may occur or become worse while driving on a rough road or when engine is vibrating (idle with
A/C on). In such a case, you will want to check for a vibration related condition. Refer to the following illustra-
tion.
Connector & Harness
Determine which connectors and wiring harness would affect the electrical system you are inspecting. Gently
shake each connector and harness while monitoring the syst em for the incident you are trying to duplicate.
This test may indicate a loose or poor electrical connection.
Hint
Connectors can be exposed to moisture. It is possible to get a thin film of corrosion on the connector termi-
nals. A visual inspection may not reveal this without disconnecting the connector. If the problem occurs inter-
mittently, perhaps the problem is caused by corrosi on. It is a good idea to disconnect, inspect and clean the
terminals on related connectors in the system.
Sensor & Relay
Gently apply a slight vibration to sensors and relays in the system you are inspecting.
This test may indicate a loose or poorly mounted sensor or relay.
Engine Compartment
There are several reasons a vehicle or engine vibration could cause an electrical complaint. Some of the
things to check for are:
• Connectors not fully seated.
• Wiring harness not long enough and is being stressed due to engine vibrations or rocking.
• Wires laying across brackets or moving components.
• Loose, dirty or corroded ground wires.
• Wires routed too close to hot components.
To inspect components under the hood, start by verifyi ng the integrity of ground connections. (Refer to Ground
Inspection described later.) First check that the system is properly grounded. Then check for loose connection
by gently shaking the wiring or components as previous ly explained. Using the wiring diagrams inspect the
wiring for continuity.
Behind the Instrument Panel
An improperly routed or improperly clamped harness can become pinched during accessory installation. Vehi-
cle vibration can aggravate a harness which is routed along a bracket or near a screw.
Under Seating Areas
SGI839
Revision: April 20092010 QX56
SERVICE INFORMATION FOR ELECTRICAL INCIDENTGI-41
< BASIC INSPECTION >
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Circuit InspectionINFOID:0000000005149608
DESCRIPTION
• In general, testing electrical circuits is an easy task if it is approached in a logical and organized method. Before beginning it is important to have all available information on the system to be tested. Also, get a thor-
ough understanding of system operation. Then you will be able to use the appropriate equipment and follow
the correct test procedure.
• You may have to simulate vehicle vibrations while te sting electrical components. Gently shake the wiring
harness or electrical component to do this.
NOTE:
Refer to GI-35, "
How to Check Terminal" to probe or check terminal.
TESTING FOR “OPENS” IN THE CIRCUIT
Before you begin to diagnose and test the system, you should rough sketch a schematic of the system. This
will help you to logically walk through the diagnosis process. Drawing the sketch will also reinforce your work-
ing knowledge of the system.
Continuity Check Method
The continuity check is used to find an open in the circui t. The digital multimeter (DMM) set on the resistance
function will indicate an open circuit as over limit (no beep tone or no ohms symbol). Make sure to always start
with the DMM at the highest resistance level.
To help in understanding the diagnosis of open circui ts, please refer to the previous schematic.
• Disconnect the battery negative cable.
• Start at one end of the circuit and work your way to the other end. (At the fuse block in this example)
• Connect one probe of the DMM to the fuse block terminal on the load side.
• Connect the other probe to the fuse block (power) side of SW1. Little or no resistance will indicate that por-
tion of the circuit has good continuity. If there were an open in the circuit, the DMM would indicate an over
limit or infinite resistance condition. (point A)
• Connect the probes between SW1 and the relay. Little or no resistance will indicate that portion of the circuit
has good continuity. If there were an open in the circuit, t he DMM would indicate an over limit or infinite resis-
tance condition. (point B)
• Connect the probes between the relay and the solenoid. Little or no resistance will indicate that portion of the
circuit has good continuity. If there were an open in the ci rcuit, the DMM would indicate an over limit or infi-
nite resistance condition. (point C)
Any circuit can be diagnosed using the approach in the previous example.
Voltage Check Method
To help in understanding the diagnosis of open circuits please refer to the previous schematic.
In any powered circuit, an open can be found by methodica lly checking the system for the presence of voltage.
This is done by switching the DMM to the voltage function.
• Connect one probe of the DMM to a known good ground.
• Begin probing at one end of the circuit and work your way to the other end.
• With SW1 open, probe at SW1 to check for voltage. voltage; open is further down the circuit than SW1.
OPEN A circuit is open when there is no continuity through a section of the circuit.
SHORT There are two types of shorts.
• SHORT CIRCUIT
When a circuit contacts another circuit and causes the normal resistance to
change.
• SHORT TO GROUND When a circuit contacts a ground source and grounds the circuit.
SGI846-A
Revision: April 20092010 QX56
GI-42
< BASIC INSPECTION >
SERVICE INFORMATION FOR ELECTRICAL INCIDENT
no voltage; open is between fuse block and SW1 (point A).
• Close SW1 and probe at relay. voltage; open is further down the circuit than the relay.
no voltage; open is between SW1 and relay (point B).
• Close the relay and probe at the solenoid. voltage; open is further down the circuit than the solenoid.
no voltage; open is between relay and solenoid (point C).
Any powered circuit can be diagnosed using the approach in the previous example.
TESTING FOR “SHORTS” IN THE CIRCUIT
To simplify the discussion of shorts in the system, please refer to the following schematic.
Resistance Check Method
• Disconnect the battery negative cable and remove the blown fuse.
• Disconnect all loads (SW1 open, relay disconnected and solenoid disconnected) powered through the fuse.
• Connect one probe of the DMM to the load side of the fuse terminal. Connect the other probe to a known good ground.
• With SW1 open, check for continuity. continuity; short is between fuse terminal and SW1 (point A).
no continuity; short is further down the circuit than SW1.
• Close SW1 and disconnect the relay. Put probes at the load side of fuse terminal and a known good ground. Then, check for continuity.
continuity; short is between SW1 and the relay (point B).
no continuity; short is further down the circuit than the relay.
• Close SW1 and jump the relay contacts with jumper wire. Put probes at the load side of fuse terminal and a known good ground. Then, check for continuity.
continuity; short is between relay and solenoid (point C).
no continuity; check solenoid, retrace steps.
Voltage Check Method
• Remove the blown fuse and disconnect all loads (i.e. SW1 open, relay disconnected and solenoid discon-
nected) powered through the fuse.
• Turn the ignition key to the ON or START position. Verify battery voltage at the battery + side of the fuse ter- minal (one lead on the battery + terminal side of the fuse block and one lead on a known good ground).
• With SW1 open and the DMM leads across both fuse terminals, check for voltage. voltage; short is between fuse block and SW1 (point A).
no voltage; short is further down the circuit than SW1.
• With SW1 closed, relay and solenoid disconnected and the DMM leads across both fuse terminals, check for voltage.
voltage; short is between SW1 and the relay (point B).
no voltage; short is further down the circuit than the relay.
• With SW1 closed, relay contacts jumped with fused jumper wire check for voltage. voltage; short is down the circuit of the relay or between the relay and the disconnected solenoid (point C).
no voltage; retrace steps and check power to fuse block.
GROUND INSPECTION
• Ground connections are very important to the proper operation of electrical and electronic circuits. Ground
connections are often exposed to moisture, dirt and other corrosive elements. The corrosion (rust) can
become an unwanted resistance. This unwanted resistance can change the way a circuit works.
• Electronically controlled circuits are very sens itive to proper grounding. A loose or corroded ground can
drastically affect an electronically controlled circuit. A poor or corroded ground can easily affect the circuit.
Even when the ground connection looks clean, there c an be a thin film of rust on the surface.
SGI847-A
Revision: April 20092010 QX56
REFRIGERATION SYSTEMHA-17
< FUNCTION DIAGNOSIS >
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FUNCTION DIAGNOSIS
REFRIGERATION SYSTEM
Refrigerant CycleINFOID:0000000005147642
REFRIGERANT FLOW
The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank,
through the front and rear evaporators, and back to the compressor. The refrigerant evaporation through the
evaporator coils are controlled by front and rear externally equalized expansion valves, located inside the front
and rear evaporator cases.
Refrigerant System ProtectionINFOID:0000000005147643
REFRIGERANT PRESSURE SENSOR
The refrigerant system is protected against excessively hi gh or low pressures by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rises above or falls below the specifications, the refriger-
ant pressure sensor detects the pressure inside the refrigerant line and sends a voltage signal to the ECM.
The ECM de-energizes the A/C relay to disengage the magnetic compressor clutch when pressure on the high
WJIA1342E
Revision: April 20092010 QX56
REFRIGERATION SYSTEMHAC-11
< FUNCTION DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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REFRIGERATION SYSTEM
Refrigerant CycleINFOID:0000000005197357
REFRIGERANT FLOW
The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank,
through the front and rear evaporators, and back to the compressor. The refrigerant evaporation through the
evaporator coils are controlled by front and rear externally equalized expansion valves, located inside the front
and rear evaporator cases.
Refrigerant System ProtectionINFOID:0000000005197358
REFRIGERANT PRESSURE SENSOR
The refrigerant system is protected against excessively hi gh or low pressures by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rises above or falls below the specifications, the refriger-
ant pressure sensor detects the pressure inside the refrigerant line and sends a voltage signal to the ECM.
The ECM de-energizes the A/C relay to disengage the magnetic compressor clutch when pressure on the high
pressure side detected by refrigerant pressu re sensor is over about 2,746 kPa (28 kg/cm
2, 398 psi), or below
about 120 kPa (1.22 kg/cm
2, 17.4 psi).
WJIA1342E
Revision: April 20092010 QX56