Page 249 of 326

SYMPTOM CHART
SYMPTOMDisplayed ``SELF-DIAG RESULTS''
on CONSULT screen.DIAGNOSTIC PROCEDURE
(Reference page)SYSTEM
(Malfunctioning part or mode)
+MIL blinking
+Engine will startIMMUPROCEDURE 1
(EL-246)IMMU
ECMPROCEDURE 2
(EL-246)ECM
+MIL blinking
+Engine does not startCHAIN OF ECM-IMMUPROCEDURE 3
(EL-247)Open circuit in battery voltage line
of IMMU circuit
Open circuit in ignition line of IMMU
circuit
Open circuit in ground line of IMMU
circuit
Open or short circuit in communica-
tion line between IMMU and ECM
ECM
IMMU
DIFFERENCE OF KEYPROCEDURE 4
(EL-249)Unregistered key
IMMU
CHAIN OF IMMU-KEYPROCEDURE 5
(EL-250)Malfunction of key ID chip
IMMU
ID DISCORD, IMM-ECMPROCEDURE 6
(EL-250)System initialisation has not yet
been completed.
ECM
IMMU
MINGLE NOISEPROCEDURE 7
(EL-251)Noise interference in communica-
tion line
LOCK MODEPROCEDURE 8
(EL-252)LOCK MODE
+MIL staying ONDON'T ERASE BEFORE CHECK-
ING ENG DIAGWORK FLOW
(EL-244)Engine trouble data and NATS
trouble data have been detected in
ECM.
+Security indicator does not oper-
ate properly.
+Engine starts properly.ÐPROCEDURE 9
(EL-253)Security indicator circuit
Security indicator
Continuation of initialisation mode
*Lighting-up mode of MIL (Malfunction Indicator Lamp)
For single malfunction of NATS: Blinking
For dual malfunctions of NATS and an engine-related part: Stays ON
For single malfunction of an engine-related part: Stays ON
NATS (Nissan Anti-Theft System)/LHD MODELS
Trouble Diagnoses (Cont'd)
EL-245
Page 251 of 326

DIAGNOSTIC PROCEDURE 3
Self-diagnostic results:
``CHAIN OF ECM-IMMU'' displayed on CONSULT screen
Con®rm SELF-DIAGNOSTIC
RESULTS ``CHAIN OF ECM-
IMMU'' displayed on CONSULT
screen.
OK
CHECK POWER SUPPLY CIRCUIT FOR
IMMU.
Check voltage between IMMU terminalj
8
and ground.
Battery voltage should exist.
OK
cNG
Check the following.
+7.5A fuse (No.
50:RD
engine,
49: TB engine,
located in the fuse and
fusible link box)
+Harness for open or
short between fuse and
IMMU connector
CHECK IGN SW. ON SIGNAL.
Check voltage between IMMU terminalj
7
and ground while ignition switch is ``ON''
position.
Battery voltage should exist.
OK
cNG
Check the following.
+10A fuse [No.
25,
located in the fuse block
(J/B)]
+Harness for open or
short between fuse and
IMMU connector
CHECK GROUND CIRCUIT FOR IMMU.
Check continuity between IMMU terminal
j
4and ground.
Continuity should exist.
OK
cNG
Repair harness.
CHECK COMMUNICATION OPEN CIR-
CUIT.
Check continuity between IMMU terminal
j
1and ECM terminalj55(RD engine),j11
(TB engine).
Continuity should exist.
OK
cNG
Repair harness.
jA
SEL333U
SEL395VA
SEL396VA
SEL397VA
SEL497V
.
.
.
.
.
NATS (Nissan Anti-Theft System)/LHD MODELS
Trouble Diagnoses (Cont'd)
EL-247
Page 252 of 326

jA
CHECK COMMUNICATION LINE SHORT
CIRCUIT.
1. Disconnect ECM connector and IMMU
connector.
2. Check continuity between IMMU termi-
nalj
1and ground.
Continuity should not exist.
3. Turn ignition switch to ON.
4. Check voltage between IMMU terminal
j
1and ground.
No voltage should exist.
OK
cNG
Repair harness.
SELF-FUNCTION CHECK
1. Connect ECM connector and
disconnect IMMU connector.
2. Turn ignition switch ``ON''.
3. Touch ``SELF-FUNCTION
CHECK'' on CONSULT
``SELECT DIAG MODE''
screen.
Touch ``START''. ECM will then
check its communication interface
by itself.
OK
cNG
+ECM is malfunctioning.
1. Replace ECM.
2. Perform initialisation
with CONSULT.
For the initialisation
procedure, refer to
``CONSULT operation
manual NATS V2.0
(GASOLINE)''.
+IMMU is malfunctioning.
1. Replace IMMU.
2. Perform initialisation with CONSULT.
For the initialisation procedure, refer to
``CONSULT operation manual NATS
V2.0''.
SEL399VA
SEL340U
SEL341U
SEL342U
.
.
.
.
NATS (Nissan Anti-Theft System)/LHD MODELS
Trouble Diagnoses (Cont'd)
EL-248
Page 253 of 326
DIAGNOSTIC PROCEDURE 4
Self-diagnostic results:
``DIFFERENCE OF KEY'' displayed on CONSULT screen
Con®rm SELF-DIAGNOSTIC
RESULTS ``DIFFERENCE OF
KEY'' displayed on CONSULT
screen.
OK
PERFORM INITIALISATION.
Perform initialisation with CONSULT.
Re-register all NATS ignition key IDs.
For the initialisation procedure, refer to
``CONSULT operation manual NATS
V2.0''.
Can the system be initialized?
Note: If the initialisation is not completed
or fails, CONSULT shows
mes-
sage on the screen.
Ye s
cNo
+IMMU is malfunctioning.
1. Replace IMMU.
2. Perform initialisation
with CONSULT.
For the initialisation
procedure, refer to
``CONSULT operation
manual NATS V2.0
(GASOLINE)''.
END.
(The ignition key was unregistered.)
SEL343U
SEL344U
SEL372U
.
.
NATS (Nissan Anti-Theft System)/LHD MODELS
Trouble Diagnoses (Cont'd)
EL-249
Page 254 of 326

DIAGNOSTIC PROCEDURE 5
Self-diagnostic results:
``CHAIN OF IMMU-KEY'' displayed on CONSULT screen
Con®rm SELF-DIAGNOSTIC
RESULTS ``CHAIN OF IMMU-
KEY'' displayed on CONSULT
screen.
OK
CHECK NATS IGNITION KEY ID CHIP.
Can the engine start with another regis-
tered NATS ignition key?
No
cYe s
+Ignition key ID chip is
malfunctioning.
1. Replace the ignition
key.
2. Perform initialisation
with CONSULT.
For the initialisation
procedure, refer to
``CONSULT operation
manual NATS V2.0
(GASOLINE)''.
+IMMU is malfunctioning.
1. Replace IMMU.
2. Perform initialisation with CONSULT.
For the initialisation procedure, refer to
``CONSULT operation manual NATS
V2.0''.
DIAGNOSTIC PROCEDURE 6
Self-diagnostic results:
``ID DISCORD, IMM-ECM'' displayed on CONSULT screen
Con®rm SELF-DIAGNOSTIC
RESULTS ``ID DISCORD, IMM-
ECM*'' displayed on CONSULT
screen.* ``ID DISCORD, IMM-ECM'':
Registered ID of IMMU is in
discord with that of ECM.
PERFORM INITIALISATION.
Perform initialisation with CONSULT.
Re-register all NATS ignition key IDs.
For the initialisation procedure, refer to
``CONSULT operation manual NATS
V2.0''.
Can the system be initialized?
Note: If the initialisation is not completed
or fails, CONSULT shows
mes-
sage on the screen.
Ye s
cNo
+ECM is malfunctioning.
1. Replace ECM.
2. Perform initialisation
with CONSULT.
For the initialisation
procedure, refer to
``CONSULT operation
manual NATS V2.0
(GASOLINE)''.
END.
(System initialisation was not completed.)
SEL373U
SEL383U
SEL372U
.
.
.
.
NATS (Nissan Anti-Theft System)/LHD MODELS
Trouble Diagnoses (Cont'd)
EL-250
Page 256 of 326

DIAGNOSTIC PROCEDURE 8
Self-diagnostic results:
``LOCK MODE'' displayed on CONSULT screen
Con®rm SELF-DIAGNOSTIC
RESULTS ``LOCK MODE'' is dis-
played on CONSULT screen.
1. Turn the ignition switch to OFF posi-
tion.
2. Turn the ignition key switch to ON posi-
tion with a registered key.
(Do not start engine.) Wait for 5 sec-
onds.
3. Return the key to the OFF position.
4. Repeat steps 2 and 3 twice (total of
three cycles).
5. Start the engine.
Can the engine start?
No
cYe s
System is OK.
(Now the system is
escaped from ``LOCK
MODE''.)
CHECK NATS IMMU INSTALLATION.
Refer to ``How to Replace NATS IMMU'' in
EL-253.
OK
cNG
Reinstall NATS IMMU cor-
rectly.
PERFORM INITIALISATION.
Perform initialisation with CONSULT.
For the initialisation procedure, refer to
``CONSULT operation manual NATS V2.0
(GASOLINE)''.
Can the system be initialized?
Note: If the initialisation is incompleted or
failed, CONSULT shows
mes-
sage on the screen.
No
cYe s
System is OK.
Go to DIAGNOSTIC PROCEDURE 5,
EL-250 to check ``CHAIN OF IMMU-KEY''.
SEL790U
SEL038V
.
.
.
.
NATS (Nissan Anti-Theft System)/LHD MODELS
Trouble Diagnoses (Cont'd)
EL-252
Page 259 of 326

System Description
NATS has the following immobiliser functions:
+Since only NATS ignition keys, whose ID nos. have been registered into the ECM and IMMU of NATS,
allow the engine to run, operation of a stolen vehicle without a NATS registered key is prevented by NATS.
That is to say, NATS will immobilize the engine if someone tries to start it without the registered key of
NATS.
+Both of the originally supplied ignition key IDs have been NATS registered.
If requested by the vehicle owner, a maximum of four key IDs can be registered into the NATS compo-
nents.
+The NATS security indicator (NATS security ind.) blinks when the ignition switch is in ``OFF'' or ``ACC''
position. Therefore, NATS warns outsiders that the vehicle is equipped with the anti-theft system.
+When NATS detects trouble, the malfunction indicator lamp (MIL) blinks.
+NATS trouble diagnoses, system initialisation and additional registration of other NATS ignition key IDs
must be carried out using CONSULT hardware and CONSULT NATS software.
When NATS initialisation has been completed, the ID of the inserted ignition key is automatically NATS
registered. Then, if necessary, additional registration of other NATS ignition key IDs can be carried out.
Regarding the procedures of NATS initialisation and NATS ignition key ID registration, refer to CONSULT
operation manual, NATS.
+When servicing a malfunction of the NATS (indicated by ¯ashing of Malfunction Indicator Lamp)
or registering another NATS ignition key ID no., it may be necessary to re-register original key
identi®cation. Therefore, be sure to receive all keys from vehicle owner.
System Composition
The immobiliser function of the NATS consists of the following:
+NATS ignition key
+NATS antenna amp. located in the ignition key cylinder
+NATS immobiliser control unit (NATS IMMU)
+Engine control module (ECM)
+NATS security indicator
+Malfunction indicator lamp (MIL)
SEL304U
NATS (Nissan Anti-Theft System)/RHD MODELS
EL-255
Page 261 of 326
CONSULT
CONSULT INSPECTION PROCEDURE
1. Turn off ignition switch.
2. Connect ``CONSULT'' to Data link connector for CONSULT.
(Data link connector for CONSULT is located behind the fuse
box cover.)
3. Insert NATS program card into CONSULT.
: Program card
NATS-E940
4. Turn on ignition switch.
5. Touch ``START''.
6. Touch ``V.2.0 (GASOLINE)''.
NOTE: ``V2.0 (GASOLINE)'' should be selected for electrically
controlled diesel and gasoline engines.
7. Perform each diagnostic test mode according to each service
procedure.
For further information, see the CONSULT Operation Manual,
NATS V2.0 (GASOLINE).
SEF532V
SEL327U
SEL328U
SEL329U
NATS (Nissan Anti-Theft System)/RHD MODELS
EL-257