2009 INFINITI QX56 relay

SCS-34
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
Compressor relay [C1802]• Driving transistor for compre
ssor relay is OFF and monitor
voltage continues at a high level for more than 10 seconds.
• Driving transistor for compre ssor relay is ON and monitor
voltage continues at a low level for more than 5 seconds. SCS-10, "DiagnosisProcedure".
Exhaust solenoid [C1803] • Driving transistor for exhaust valve solenoid is OFF and
monitor voltage continues at a high level for more than 10
seconds.
• Driving transistor for exhaust valve solenoid is ON and mon- itor voltage continues at a low level for more than 5 seconds. SCS-11,
"DiagnosisProcedure".
Vehicle height adjusting malfunc-
tion (compressor)[C1804] Continuous compressor relay ON time is more than 120 sec-
onds. SCS-12,
"DiagnosisProcedure".
Vehicle height adjusting malfunc-
tion (exhaust solenoid)[C1805] Continuous exhaust valve solenoid ON time is more than 120
seconds. SCS-13,
"DiagnosisProcedure".
Vehicle height sensor locking mal-
function [C1806] Output sensor voltage variation
±0.02V is more than 100 sec-
onds when vehicle height range is normal. SCS-14, "
Diagnosis Proce-
dure".
Sensor 5V malfunction [C1807] Sensor reference voltage is less than 0.8V or more than 6V for
20 seconds. SCS-15,
"DiagnosisProcedure"
Integral time malfunction by sup-
plying air [C1808]A suspension air compressor ON request has been in effect
for 180 seconds and the suspension air compressor has not
activated during that time. SCS-16,
"DiagnosisProcedure".
Revision: December 20092009 QX56

SUSPENSION CONTROL SYSTEMSCS-35
< SYMPTOM DIAGNOSIS >
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SYMPTOM DIAGNOSIS
SUSPENSION CONTROL SYSTEM
Symptom TableINFOID:0000000003772354
AIR LEVELIZER
Symptom Possible causeReference page
Inoperative • Suspension control unit
• Compressor motor relay
• Suspension air compressorSCS-36, "
Diagnosis Proce-
dure"
System does not raise • Suspension control unit
• Height sensor
• Compressor motor relay
• Suspension air compressor
• Leak in system
• Restriction in systemSCS-37, "Diagnosis Proce-
dure"
System does not lower
• Suspension control unit
• Height sensor
• Compressor motor relay
• Suspension air compressor
• Restriction in systemSCS-38, "Diagnosis Proce-
dure"
CK SUSP indicator lamp always ON with key ON
• CK SUSP indicator lamp control circuit
• Suspension control unitSCS-25, "Description"
Revision: December 20092009 QX56

INTELLIGENT KEY SYSTEM/ENGINE START FUNCTIONSEC-7
< FUNCTION DIAGNOSIS > [WITH INTELLIGENT KEY SYSTEM]
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FUNCTION DIAGNOSIS
INTELLIGENT KEY SYSTEM /ENGINE START FUNCTION
System DiagramINFOID:0000000003775868
System DescriptionINFOID:0000000003775869
INPUT/OUTPUT SIGNAL CHART
Intelligent Key Unit
IPDM E/R
BCM
SYSTEM DESCRIPTION
• The engine start function of Intelligent Key system is a system that makes it possible to start and stop the
engine without using the key. It verifies the electr onic ID using two-way communications when pressing the
ignition knob switch while carrying the Intelligent Key, which operates based on the results of electronic ID
verification for Intelligent Key using two-way communications between the Intelligent Key and the vehicle.
NOTE:
The driver should carry the Intelligent Key at all times.
Switch/Input signal Input signal to
Intelligent Key unit Intelligent Key unit
function Actuator/Output signal
Key switch Mechanical key
(insert/remove)
Engine start function• KEY warning lamp/buzzer
• Steering lock solenoid
• Starter relay requ
est (to IPDM E/R)
• Inside key antenna
(Front and rear center console, over-
head console, luggage compartment)
• Key interlock solenoid
Ignition knob switch
Ignition knob
(push/release)
Steering lock solenoid Steering lock
(lock/unlock)
Inside key antenna
(Front and rear center console, over-
head console, luggage compartment) Intelligent key
(inside antenna detection
area or not.)
Switch/Input signal Input signal to
IPDM E/R IPDM E/R function
Actuator/Output signal
Park/neutral position switch P, N range Engine start function• Starter relay
• Starter motor
Switch/Input signal Input signal to
BCM BCM function
Actuator/Output signal
Key switch Brake
(press/release)
Engine start function• Inside key antenna
(Front and rear center console, over-
head console, luggage compartment)
ALKIA0925GB
Revision: December 20092009 QX56

SEC-8
< FUNCTION DIAGNOSIS >[WITH INTELLIGENT KEY SYSTEM]
INTELLIGENT KEY SYSTEM/ENGINE START FUNCTION
• Intelligent Key has 2 IDs (for Intelligent Key and for
NATS). It can perform the door lock/unlock operation and
the engine start operation when the registered Intelligent Key is carried.
• When the Intelligent Key battery is discharged, it can be used as emergency back-up by inserting the
mechanical key set in the Intelligent Key to the ignition key cylinder. At that time, perform the NATS ID verifi-
cation. If it is used when the Intelligent Key is carried, perform the Intelligent Key ID verification.
• If the ID is successfully verified, and when the igniti on knob switch is pressed, steering lock will be released
and initiating the engine will be possible.
• The door lock/unlock operation can be performed when the Intelligent Key battery is discharged, by operat-
ing the driver door key cylinder using the mechanical key set in the Intelligent Key.
• Up to 4 Intelligent Keys can be registered (including the standard Intelligent Key) on request from the owner. NOTE:
• Refer to DLK-21, "
INTELLIGENT KEY : System Description" for any functions other than engine start func-
tion of Intelligent Key system.
PRECAUTIONS FOR INTELLIGENT KEY SYSTEM
• For vehicles equipped with the Intelligent Key system , the transponder [the chip for NATS ID verifi-
cation] is integrated into the Inte lligent Key. Therefore, the Intellig ent Key alone is capable of provid-
ing security clearance for the engine to start. Also, when the mechanical key alone is inserted into
the key cylinder, performs the NATS ID verification to allow the engine to start. For vehicles without
Intelligent Key system, the transponder is integrated into the mechanical key which must be inserted
into the key cylinder to perform the NATS ID verification to allow the engine to start.
OPERATION WHEN INTELLIGENT KEY IS CARRIED
1. When the ignition knob switch is ON, the Intelligent Key unit transmits the request signal to the Intelligent
Key.
2. The Intelligent Key receives the request signal and transmits the Intelligent Key ID signal to the Intelligent Key unit.
3. The Intelligent Key unit receives the Intelligent Key ID signal and verifies it with the registered ID.
4. Intelligent Key unit transmits the steering lock/unlock signal to steering lock solenoid if the verification results are OK. For detail of key warning message operation, refer to DLK-38, "
System Description".
5. Release of the steering lock.
6. BCM transmits the starter request signal via CAN communication to IPDM E/R and turns the starter relay in IPDM E/R ON if BCM judges that the engine start condition is satisfied.
7. IPDM E/R turns the starter control relay ON when receiving the starter request signal.
8. When shift position is in P or N position, battery power is supplied through the starter relay and operate the starter motor and to start the cranking.
CAUTION:
If a malfunction is detected in the Intelligent Key system, the “KEY” warning message will be dis-
played in the combination meter. At th at time, the engine cannot be started.
OPERATION RANGE
Engine can be started when Intelligent Key is inside the vehicle. However, sometimes engine might not start
when Intelligent Key is on instrument panel or in glove box.
OPERATION WHEN MECHANICAL KEY IS USED
When the Intelligent Key battery is discharged, performs the NATS ID verification between the integrated tran-
sponder and BCM by inserting the mechanical key into the key cylinder, and then the engine can be started.
For details relating to starting the engine using mechanical key, refer to SEC-11, "
System Description".
STEERING LOCK OPERATION
Steering is locked by steering lock solenoid when ignition switch is in the LOCK position (the ignition knob is
released) and key switch is OFF (key is removed from ignition key cylinder).
Revision: December 20092009 QX56

SEC-16
< FUNCTION DIAGNOSIS >[WITH INTELLIGENT KEY SYSTEM]
VEHICLE SECURITY SYSTEM
Condition of Deacti
vating The System
When one of the following operations is performed, the armed phase is canceled.
• Unlock the doors with Intelligent Key or door request switch.
• Use the mechanical key to unlock the driver door using the door key cylinder.
Component Parts LocationINFOID:0000000003775878
ALKIA0961ZZ
1. BCM M18, M19, M20
(view with instrument panel LH removed) 2. IPDM E/R E122, E124
(view with co ver removed) 3. Horn relay H-1
4. Main power window and door lock/unlock switch D7, D8 5. Power window and door lock/unlock
switch RH D105 6. Front door lock assembly LH (key cylin-
der switch) D14
Revision: December 20092009 QX56

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
SEC-99
< ECU DIAGNOSIS > [WITH INTELLIGENT KEY SYSTEM]
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Te r m i n a l Wire
color Signal name Signal
input/
output Measuring condition
Reference value(Approx.)
Igni-
tion
switch Operation or condition
1 B/Y Battery power supply Input OFF —Battery voltage
2 R Battery power supply Input OFF —Battery voltage
3BRECM relay Output— Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
4W/LECM relay Output— Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
6L Throttle control motor
relay Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
7 W/B ECM relay control Input — Ignition switch ON or START
0V
Ignition switch OFF or ACC Battery voltage
8 R/B Fuse 54 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
10 G Fuse 45 Output ONDaytime light system active
0V
Daytime light system inactive Battery voltage
11 Y/B A/C compressor Output ON or
START A/C switch ON or defrost A/C
switch
Battery voltage
A/C switch OFF or defrost A/C
switch 0V
12 L/W Ignition switch sup-
plied power Input —OFF or ACC
0V
ON or START Battery voltage
13 B/Y Fuel pump relay Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
14 Y/R Fuse 49 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
15 LG/B Fuse 50 (VDC) Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
15 GR Fuse 50 (ABS) Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
16 G Fuse 51 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
17 W Fuse 55 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
19 W/R Starter motor Output START—Battery voltage
21 BR Ignition switch sup-
plied power
Input —OFF or ACC
0V
START Battery voltage
22 G Battery power supply Output OFF —Battery voltage
23 GR/W Door mirror defogger
output signal Output —When rear defogger switch is
ON
Battery voltage
When raker defogger switch is
OFF 0V
Revision: December 20092009 QX56

SEC-100
< ECU DIAGNOSIS >[WITH INTELLIGENT KEY SYSTEM]
IPDM E/R (INTELLIGENT POWER DI
STRIBUTION MODULE ENGINE ROOM)
24 L Cooling fan relay Output — Conditions correct for cooling
fan operation
Battery voltage
Conditions not correct for
cooling fan operation 0V
26 P/L Headlamp aiming mo-
tors Output —Lighting
switch 2nd
position or
AUTO, head-
lamp aiming
switch in po-
sition OFF
0V
ON Battery voltage
27 W/B Fuse 38 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
30 W Fuse 53 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
32 L Wiper low speed sig-
nal OutputON or
START Wiper switch OFF
Battery voltage
LO or INT 0V
35 L/B Wiper high speed sig-
nal OutputON or
START Wiper switch OFF, LO, INT Battery voltage
HI 0V
37 Y Power generation
command signal
Output —Ignition switch ON
6.3 V
40% is set on "Active test,"
"ALTERNATOR DUTY" of
"ENGINE" 3.8 V
40% is set on "Active test,"
"ALTERNATOR DUTY" of
"ENGINE" 1.4 V
38 B Ground Input ——0V
39 L CAN-H — ON— —
40 P CAN-L — ON— —
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value(Approx.)
Igni-
tion
switch Operation or condition
JPMIA0001GB
JPMIA0002GB
JPMIA0003GB
Revision: December 20092009 QX56

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
SEC-101
< ECU DIAGNOSIS > [WITH INTELLIGENT KEY SYSTEM]
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41 Y/B Hood switch Input —Hood closed OFF
0V
Hood open ON Battery voltage
42 GR Oil pressure switch Input — Engine running
Battery voltage
Engine stopped 0V
43 L/Y Wiper auto stop signal Input ON or
START Wiper switch OFF, LO, INT Battery voltage
44 BR Daytime light relay
control Input ONDaytime light system active
0V
Daytime light system inactive Battery voltage
45 G/W Horn relay control Input ON When door locks are operated
using keyfob or Intelligent Key
(OFF
→ ON)* Battery voltage
→ 0V
46 GR Fuel pump relay con-
trol
Input —Ignition switch ON or START
0V
Ignition switch OFF or ACC Battery voltage
47 O Throttle control motor
relay control
Input —Ignition switch ON or START
0V
Ignition switch OFF or ACC Battery voltage
48 B/R Starter relay (inhibit
switch) InputON or
START Selector lever in "P" or "N"
0V
Selector lever any other posi-
tion Battery voltage
49 R/L Trailer tow relay Output ON Lighting
switch must
be in the 1st
positionOFF
0V
ON Battery voltage
50 W/R Front fog lamp (LH) Output ON or
START Lighting
switch must
be in the 2nd
position
(LOW beam
is ON) and
the front fog
lamp switch OFF
0V
ON Battery voltage
51 W/R Front fog lamp (RH) Output ON or
START Lighting
switch must
be in the 2nd
position
(LOW beam
is ON) and
the front fog
lamp switch OFF
0V
ON Battery voltage
52 L LH low beam head-
lamp Output — Lighting switch in 2nd position Battery voltage
54 R/Y RH low beam head-
lamp Output — Lighting switch in 2nd position Battery voltage
55 G LH high beam head-
lamp Output —Lighting switch in 2nd position
and placed in HIGH or PASS
position Battery voltage
56 L/W RH high beam head-
lamp Output —Lighting switch in 2nd position
and placed in HIGH or PASS
position Battery voltage
57 R/L Parking, license, and
tail lamp
Output ONLighting
swi
t

ch 1st po-
sition OFF
0V
ON Battery voltage
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value(Approx.)
Igni-
tion
switch Operation or condition
Revision: December 20092009 QX56