2009 INFINITI QX56 engine

INTELLIGENT KEY SYSTEM/ENGINE START FUNCTIONSEC-9
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Component Parts LocationINFOID:0000000003775870
ALKIA0958ZZ
1. BCM M18, M20 (view with instrument panel LH removed) 2. Intelligent Key unit M70
(view with instrument panel LH removed) 3. IPDM E/R
E119, E120, E122, E124
4. ECM E16 5. Key switch and ignition knob switch M12
(view with st eering column removed) 6. Steering lock solenoid M15
7. Remote keyless entry receiver M25 (view with instrume nt panel RH removed) 8. A/T shift selector (park position switch)
M203
(view with center console removed) 9. Inside key antenna 3 (front of cen-
ter console) M210
(view with center console removed)
Revision: December 20092009 QX56

SEC-10
< FUNCTION DIAGNOSIS >[WITH INTELLIGENT KEY SYSTEM]
INTELLIGENT KEY SYSTEM/ENGINE START FUNCTION
Component Description
INFOID:0000000003775871
10. Inside key antenna 1 (rear of center con- sole) M209 11. Inside key antenna 4 (overhead console
area) R210
(view with overhead console removed) 12. Inside key antenna 2 (luggage
compartment) B76
(view with rear carpet removed)
13. Intelligent Key warning buzzer E25 14. Combination meter M23, M24 15. Vehicle security indicator lamp
Item Function
Intelligent Key unit Receives lock/unlock signal from remote keyless entry receiver, and then transmits to BCM.
BCM Verifies the received signal from Intelligent Key, then informs ECM whether to allow engine start.
Remote keyless entry receiver Receives lock/unlock signal from th e Intelligent Key, and then transmits to Intelligent Key unit.
Intelligent Key Transmits button operation to remote keyless entry receiver.
Steering lock solenoid Locks the steering wheel when the ignition key is off and the Intelligent Key is outside the vehicle.
Inside key antenna Detects if Intelligent Key is inside the vehicle.
Intelligent Key warning buzzer Warns the user of the lock/unlock condition and inappropriate operations with the buzzer sound.
A/T shift selector (park position
switch) Detects whether the shift lever is in park.
Revision: December 20092009 QX56

INFINITI VEHICLE IMMOBILIZER SYSTEM-NATSSEC-11
< FUNCTION DIAGNOSIS > [WITH INTELLIGENT KEY SYSTEM]
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INFINITI VEHICLE IMMOBILIZER SYSTEM-NATS
System DiagramINFOID:0000000003775872
System DescriptionINFOID:0000000003775873
INPUT/OUTPUT SIGNAL CHART
Intelligent Key Unit
BCM
SYSTEM DESCRIPTION
NATS (Nissan Anti-Theft System) has the following immobilizer functions:
• Engine immobilizer shows high anti-theft performance to prevent engine from starting by other than the owner.
• Only a key with key ID registered in BCM and ECM can start engine, and shows high anti-theft performance to prevent key from being copied or stolen.
• Security indicator always flashes with mechanical key removed condition (key switch: OFF) and ignition
knob released condition on LOCK posit ion (ignition knob switch: OFF).
• Therefore, NATS warns outsiders that the vehicl e is equipped with the anti-theft system. Refer to SEC-15,
"System Description".
• If system detects malfunction, security indicator illuminates when ignition switch is turned to ON position.
• If the owner requires, ignition key ID or mechanical key ID can be registered for up to 4 keys.
• During trouble diagnosis or when the following parts have been replaced, and if mechanical key is added, registration* is required.
*1: All keys kept by the owner of the vehi cle should be registered with mechanical key.
-ECM
-BCM
LIIA2537E
Switch/Input signal Input signal to BCM BCM function Actuator/Output signal
Ignition knob switch Ignition knob
(push/release)
NATS• Steering lock solenoid
Key switch
Mechanical key
(Insert/remove)
Steering lock solenoid Ste eri ng
(lock/unlock)
ECM Engine status signal
Switch/Input signalInput signal to BCM BCM function Actuator/Output signal
NATS antenna amp. Key ID
NATS• Security indicator lamp
• Starter request
ECM Engine status signal
Revision: December 20092009 QX56

SEC-12
< FUNCTION DIAGNOSIS >[WITH INTELLIGENT KEY SYSTEM]
INFINITI VEHICLE IMMOBILIZER SYSTEM-NATS
- Mechanical key
- Intelligent Key unit
- Remote keyless entry receiver
- Steering lock solenoid
• NATS trouble diagnosis, system initialization and additional
registration of other mechanical key IDs must be
carried out using CONSULT-III.
When NATS initialization has been completed, the ID of the inserted mechanical key or mechanical key IDs
can be carried out.
• Possible symptom of NATS malfunction is “Engine cannot start”. Identify the possible causes according to
“Work Flow”, Refer to SEC-3, "
Work Flow".
• If ECM other than Genuine NISSAN is installed, t he engine cannot be started. For ECM replacement proce-
dure, refer to SEC-6, "
ECM RE-COMMUNICATING FUNCTION : Description".
PRECAUTIONS FOR KEY REGISTRATION
• The key registration is a procedure that erases the current NATS ID once, and then re-registers a new ID.
Therefore the registered Intelligent Key is necessary fo r this procedure. Before starting the registration oper-
ation collect all registered Intelligent Keys from the customer.
• The NATS ID registration is the procedure that regi sters the ID stored into the transponder (integrated in
mechanical key) to BCM.
The Intelligent Key ID registration is the procedur e that registers the ID to Intelligent Key unit.
• When performing the Intelligent Key system registration only, the engine cannot be started by inserting the key into the key cylinder. When performing the NATS registration only, the engine cannot be started by using
the mechanical key.
SECURITY INDICATOR
• Always flashes with ignition knob released (ignition knob switch: LOCK) condition on ignition knob LOCKposition.
• Always flashes with ignition knob released (ignition knob switch: LOCK) condition on mechanical key removed position.
MAINTENANCE INFORMATION
CAUTION:
It is necessary to perform NATS ID registration when replacing any of the following part.
If it's not (or fail to do so), the electrical system may not operate properly.
• Intelligent Key unit
• BCM
•ECM
• Mechanical key
• Steering lock solenoid
• NATS antenna amp.
Revision: December 20092009 QX56

B2190, P1614 NATS ANTENNA AMP.SEC-27
< COMPONENT DIAGNOSIS > [WITH INTELLIGENT KEY SYSTEM]
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B2190, P1614 NATS ANTENNA AMP.
DescriptionINFOID:0000000003775894
Performs ID verification through BCM and NATS antenna amplifier when ignition knob switch is pressed.
Prohibits the release of steering lock or start of engine when an unregistered ID of mechanical key is used.
DTC LogicINFOID:0000000003775895
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
1. Insert mechanical key into the key cylinder.
2. Press the ignition knob switch.
3. Check “Self diagnostic result” with CONSULT-III.
Is DTC detected?
YES >> Refer to SEC-27, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000003775896
1.CHECK NATS ANTENNA AMP. INSTALLATION
Check NATS antenna amp. installation. Refer to S E C - 111 , "
Removal and Installation".
Is the inspection result normal?
YES >> GO TO 2
NO >> Reinstall NATS antenna amp. correctly.
2.CHECK NVIS (NATS) IGNITION KEY ID CHIP
Start engine with another registered NATS ignition key.
Does the engine start?
YES >> • Ignition key ID chip is malfunctioning. • Replace the ignition key.
• Perform initialization with CONSULT-III.For initialization, refer to “CONSULT-III Operation Manual”.
NO >> GO TO 3
3.CHECK POWER SUPPLY FOR NATS ANTENNA AMP.
1. Turn ignition switch ON.
2. Check voltage between NATS antenna amp. connector M21 terminal 1 and ground.
DTC No. Trouble diagnosis
name DTC detecting condition
Possible cause
B2190
NATS ANTENNA
AMP • Inactive communication between NATS antenna
amp. and BCM.
• Mechanical key is malfunctioning. • Harness or connectors
(The NATS antenna amp. circuit is
open or shorted)
• Mechanical key
• NATS antenna amp.
•BCM
P1614
Revision: December 20092009 QX56

SEC-30
< COMPONENT DIAGNOSIS >[WITH INTELLIGENT KEY SYSTEM]
B2191, P1615 DIFFERENCE OF KEY
B2191, P1615 DIFFERENCE OF KEY
DescriptionINFOID:0000000003775897
Performs ID verification through BCM when ignition knob switch is pressed.
Prohibits the release of steering lock or start of engine when an unregistered ID of mechanical key is used.
DTC LogicINFOID:0000000003775898
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
1. Insert mechanical key into the key cylinder.
2. Press the ignition knob switch.
3. Check “Self diagnostic result” with CONSULT-III.
Is DTC detected?
YES >> Refer to SEC-30, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000003775899
1.PERFORM INITIALIZATION
Perform initialization with CONSULT-III. Re-register all mechanical keys.
For initialization and registration of mechanical key. Refer to “CONSULT-III Operation Manual”.
Can the system be initialized and can the engine be started with re-registered mechanical key?
YES >> Mechanical key was unregistered.
NO >> BCM is malfunctioning. • Replace BCM. Refer to BCS-56, "
Removal and Installation".
• Perform initialization again
DTC No. Trouble diagnosis
name DTC detecting condition
Possible cause
B2191 DIFFERENCE OF
KEY The ID verification results between BCM and me-
chanical key are NG. The registration is necessary.
Mechanical key
P1615
Revision: December 20092009 QX56

B2192, P1611 ID DISCORD, IMMU-ECMSEC-31
< COMPONENT DIAGNOSIS > [WITH INTELLIGENT KEY SYSTEM]
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B2192, P1611 ID DISCORD, IMMU-ECM
DescriptionINFOID:0000000003775900
BCM performs the ID verification with ECM that allows the engine to start. BCM starts the communication with
ECM if ignition switch is turned ON and starts the engi ne if the ID is OK. ECM prevents the engine from start-
ing if the ID is not registered.
DTC LogicINFOID:0000000003775901
DTC DETECTION LOGIC
NOTE:
• If DTC B2192 is displayed with DTC U1000, first perform the trouble diagnosis for DTC U1000. Refer to
SEC-22, "
DTC Logic".
• If DTC B2192 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer to
SEC-23, "
DTC Logic".
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Check “Self diagnostic result” with CONSULT-III.
Is DTC detected?
YES >> Refer to SEC-31, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000003775902
1.PERFORM INITIALIZATION
Perform initialization with CONSULT-III. Re-register all mechanical keys.
For initialization and registration of mechanical key. Refer to “CONSULT-III Operation Manual”.
Can the system be initialized and can the engine be started with re-registered mechanical key?
YES >> ID was unregistered.
NO >> GO TO 2
2.PEPLACE BCM
1. Replace BCM. Refer to BCS-56, "
Removal and Installation".
2. Perform initialization with CONSULT- III. Re-register all mechanical keys.
For initialization and registration of mechanical key. Refer to “CONSULT-III Operation Manual”.
Can the system be initialized and can the engine be started with re-registered mechanical key?
YES >> BCM is malfunctioning.
NO >> GO TO 3
3.PEPLACE ECM
1. Replace ECM. Refer to Removal and Installation.
2. Perform initialization with CONSULT- III. Re-register all mechanical keys.
For initialization and registration of mechanical key. Refer to “CONSULT-III Operation Manual”.
Can the system be initialized and can the engine be started with re-registered mechanical key?
YES >> ECM is malfunctioning.
NO >> GO TO 4
4.CHECK INTERMITTENT INCIDENT
Refer to GI-38, "
Intermittent Incident".
DTC No. Trouble diagnosis
name DTC detecting condition
Possible cause
B2192 ID DISCORD BCM-
ECM The ID verification results between BCM and ECM
are NG. The registration is necessary. •BCM
•ECM
P1611
Revision: December 20092009 QX56

B2193, P1612 CHAIN OF ECM-IMMUSEC-33
< COMPONENT DIAGNOSIS > [WITH INTELLIGENT KEY SYSTEM]
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B2193, P1612 CHAIN OF ECM-IMMU
DescriptionINFOID:0000000003775903
BCM performs the ID verification with ECM that allows the engine to start. BCM starts the communication with
ECM if ignition switch is turned ON and starts the engi ne if the ID is OK. ECM prevents the engine from start-
ing if the ID is not registered.
DTC LogicINFOID:0000000003775904
DTC DETECTION LOGIC
NOTE:
• If DTC B2193 is displayed with DTC U1000, first perform the trouble diagnosis for DTC U1000. Refer to
SEC-22, "
DTC Logic".
• If DTC B2193 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer to
SEC-23, "
DTC Logic".
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Check “Self diagnostic result” with CONSULT-III.
Is DTC detected?
YES >> Refer to SEC-33, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000003775905
1.REPLACE BCM
1. Replace BCM. Refer to BCS-56, "
Removal and Installation".
2. Perform initialization with CONSULT-III. For initialization, refer to “CONSULT-III Operation Manual”.
Does the engine start?
YES >> BCM was malfunctioning.
NO >> ECM is malfunctioning. • Replace ECM.
• Perform ECM re-communicating function.
DTC No. Trouble diagnosis
name DTC detecting condition
Possible cause
B2193 CHAIN OF BCM-
ECM Inactive communication between ECM and BCM • Harness or connectors
(The CAN communication line is
open or short)
•BCM
•ECM
P1612
Revision: December 20092009 QX56