1998 NISSAN PICK-UP Repair Manual

System Description
NATS has the following immobiliser functions:
lSince only NATS ignition keys, whose IDs. have been registered into the NATS immobiliser control unit
(NATS IMMU), allow the engine to run, operation of a stolen vehicle without a NATS registered key is
prevented by NATS.
lBoth 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.
lThe 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.
lIf NATS detects trouble, the NATS security indicator comes on while engine is running or ignition switch
is in ``ON'' position.
lWhen servicing NATS (trouble diagnoses, NATS initialisation and additional registration of other NATS
ignition key IDs), CONSULT hardware and CONSULT NATS software is necessary.
lThere are two types of NATS initialisation, one is ``SYSTEM INITIALISATION'' and another is ``IMMU
INITIALISATION''.
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 V2.0 (Diesel).
lWhen servicing a malfunction of the NATS (indicated by lighting of NATS security ind.) or reg-
istering another NATS ignition key ID no., it may be necessary to re-register original key identi-
fication. Therefore, be sure to receive all keys from vehicle owner.
System Composition
The immobiliser function of the NATS consists of the following:
lNATS ignition key
lNATS antenna amp. located in the ignition key cylinder
lNATS immobiliser control unit (NATS IMMU)
lCoded solenoid unit installed in the injection pump assembly (CSOLU)
lNATS security indicator (NATS security ind.)
SEL549U
NATS (Nissan Anti-Theft System)/Diesel engine
EL-199

Wiring Diagram Ð NATS Ð/LHD Models
HEL389A
NATS (Nissan Anti-Theft System)/Diesel engine
EL-200

Wiring Diagram Ð NATS Ð/RHD Models
HEL390A
NATS (Nissan Anti-Theft System)/Diesel engine
EL-201

CONSULT
CONSULT INSPECTION PROCEDURE
1. Turn off ignition switch.
2. Connect ``CONSULT'' to Data link connector for CONSULT.
3. Insert NATS program card into CONSULT.
b
: Program card
NATS-E940
4. Turn on ignition switch.
5. Touch ``START''.
6. Touch ``V.2.0 (DIESEL)''.
7. Perform each diagnostic test mode according to each service
procedure.
For further information, see the CONSULT Operation
Manual, NATS V2.0 (Diesel).
NOTE:
Two types of initialisation (system initialisation and IMMU initiali-
sation) are available. For details, refer to ``INITIALISATION'' in
next page.
SEF056U
SEL327U
SEL662U
SEL663U
SEL718U
NATS (Nissan Anti-Theft System)/Diesel engine
EL-202

CONSULT DIAGNOSTIC TEST MODE FUNCTION
CONSULT diagnostic test mode Description
C/U INITIALISATION Two types of initialisation are available. For details, refer to ``INITIALISATION'' shown below.
SELF-FUNCTION CHECK IMMU checks its own NATS communication interface.
SELF-DIAGNOSTIC RESULTS Self-diagnostic results can be read and erased quickly.
INITIALISATION
Initialisation type Description
SYSTEM INITIALISATIONAll registered ignition key IDs in IMMU and CSOLU can be registered.
It takes around 16 minutes.
When the following component is replaced, this initialisation is required.
lIMMU
lCSOLU
IMMU INITIALISATIONAll registered ignition key IDs in IMMU can be initialised and new IDs can be registered.
When the following component is replaced or new NATS ignition key is registered, this ini-
tialisation is required.
lNATS ignition key
NOTE:
When any of initialisation is performed, all of ID codes previously registered will be erased. So all of NATS
ignition keys must be registered again.
If unregistered key is used to try to start the engine, the system may show ``KEY ID [DIFFERENCE]'' as a
self-diagnostic result on CONSULT screen.
HOW TO READ SELF-DIAGNOSTIC RESULTS
SEL664U
NATS (Nissan Anti-Theft System)/Diesel engine
CONSULT (Cont'd)
EL-203

SELF-DIAGNOSTIC RESULTS ITEM CHART
Detected items (Screen terms) Description Reference page
IMMU IMMU is malfunctioning. EL-207
CSOLUIMMU received the signal from CSOLU that CSOLU is malfunc-
tioning.EL-207
CHAIN OF CSOLU-IMM Communication impossible between CSOLU and IMMU. EL-208
KEY ID [DIFFERENCE]IMMU can receive the key ID signal but the result of ID verifica-
tion between key ID and IMMU is NG.EL-210
KEY ID [NO INPUT]IMMU cannot receive the key ID signal. In the case of multiple
malfunctions, just this item can be displayed prior to the other
malfunctioning items.EL-211
ID DSCORD, IMM-CSLUThe result of ID verification between IMMU and CSOLU is NG.
System initialisation is required.EL-213
NOTE:
When CONSULT shows ``IMPOSSIBLE TO PROCEED'' displayed on its screen, it means that CONSULT
fails to access to the NATS. In this case, perform diagnostic procedure 7, EL-214.
NATS (Nissan Anti-Theft System)/Diesel engine
CONSULT (Cont'd)
EL-204

Trouble Diagnoses
WORK FLOW
CHECK IN
Listen to customer complaints or request. (Get symptoms.)
TROUBLEKEY SERVICE REQUEST (Additional key ID registration)
.Verify the lighting of security ind. with ignition switch in ``ON''
position.IMMU INITIALISATION
[Refer to CONSULT operation
manual NATS V2.0 (Diesel).]
cUsing the CONSULT program card for NATS check the ``SELF-
DIAG RESULTS'' with CONSULT.
Information about self-diagnostic results referring to NATS is
displayed on CONSULT.
Turn ignition switch ``OFF''.
Repair NATS.
(If necessary, carry out ``SELF-FUNCTION CHECK'' or ``INI-
TIALISATION'' with CONSULT.)
Turn ignition switch ``ON''.
Erase the NATS ``SELF-DIAG RESULTS'' by using CONSULT.
(Touch ``ERASE''.)
Turn ignition switch ``OFF''.
Wait approx. 5 seconds and turn ignition switch ``ON''.
NGVerify no lighting of security ind.
OK
CHECK OUT
.
.
.
.
.
.
.
.
.
.
.
.
NATS (Nissan Anti-Theft System)/Diesel engine
EL-205

SYMPTOM CHART
SymptomDisplayed ``SELF-DIAG
RESULTS'' on CONSULT
screenDiagnostic Procedure
(Reference page)System
(Malfunctioning part or mode)
lNo lighting/lighting of secu-
rity indicator with ignition
switch in ``ON'' position
lHard to start engineIMMU PROCEDURE 1
(EL-207)IMMU
lLighting of security indica-
tor with ignition switch in
``ON'' position
lHard to start engineCSOLU PROCEDURE 2
(EL-207)CSOLU
CHAIN OF CSOLU-IMM PROCEDURE 3
(EL-208)Open circuit in ignition line of CSOLU
Open circuit in ground line of CSOLU
Open or short circuit in communication line
between IMMU and CSOLU
IMMU
CSOLU
KEY ID
[NO INPUT]PROCEDURE 5
(EL-211)Open or short circuit in communication line
between ANT/AMP and IMMU
Open circuit in power source line of ANT/
AMP circuit
Open circuit in ground of ANT/AMP circuit
Malfunction of key ID chip
IMMU
Antenna amp.
ID DISCORD, IMM-CSLU PROCEDURE 6
(EL-213)System initialisation has not yet been com-
pleted.
CSOLU
IMMU
lHard to start engine
lLighting of security indica-
tor with ignition switch in
``ON'' position (See note)KEY ID
[DIFFERENCE]PROCEDURE 4
(EL-210)Unregistered key
lHard to start engine
lNo lighting of security indi-
cator.
lImpossible to proceed with
the CONSULT diagnosesAfter touch ``START'',
CONSULT screen dis-
plays ``IMPOSSIBLE TO
PROCEED''.PROCEDURE 7
(EL-214)Open or short circuit in communication line
between IMMU and CONSULT data link
connector
Open or short circuit in antenna amp. power
source circuit between IMMU and antenna
amp.
Open circuit in power source line of IMMU
circuit
Open circuit in ignition line of IMMU circuit
Open circuit in ground line of IMMU circuit
IMMU
lNATS security ind. does
not blink with ignition
switch in ``OFF'' or ``ACC''.
lEngine starts properly.Ð PROCEDURE 8
(EL-216)NATS security ind.
Open circuit between fuse and NATS IMMU
Continuation of initialisation mode
NOTE: NATS security ind. may light off for 1 minute after ignition switch is turned to ``OFF'' position.
NATS (Nissan Anti-Theft System)/Diesel engine
Trouble Diagnoses (Cont'd)
EL-206