1998 NISSAN PICK-UP ECU

NATS Audio Link/For Europe LHD (KA24E)
DESCRIPTION
The Europe LHD model with KA24E engine has a NATS-linked anti-theft function with radio as optional
equipment.
The link with the NATS IMMU implies that the radio can basically only be operated if connected to the
matching NATS IMMU to which the radio was initially fitted on the production line.
Since radio operation is impossible after the link with the NATS is disrupted theft of the radio unit is basi-
cally useless since special equipment is required to reset the radio.
Initialisation process for radios that are linked to the NATS IMMU
New radios will be delivered to the factories in the ``NEW'' state, i.e. ready to be linked with the vehicle's
NATS.
When the radio in ``NEW'' state is first switched on at the factory, it will start up communication with the
vehicle's immobiliser control unit (IMMU) and send a code (the ``Radio Code'') to the IMMU. The IMMU will
then store this code, which is unique to each radio, in its (permanent) memory.
Upon receipt of the code by the IMMU, the NATS will confirm correct receipt of the radio code to the radio.
Hereafter, the radio will operate as normal.
During the initialisation process, ``NEW'' is displayed on the radio display. Normally though, communication
between Radio and IMMU takes such a short time (300 ms) that the radio seems to switch on directly with-
out showing ``NEW'' on its display.
Normal operation
Each time the radio is switched on afterwards, the radio code will be verified between the radio unit and the
NATS before the radio becomes operational. During the code verification process, ``WAIT'' is shown on the
radio display. Again, the communication takes such a short time (300 ms) that the radio seems to switch on
directly without showing ``WAIT'' on its display.
When the radio is locked
In case of a radio being linked with the vehicle's NATS (immobiliser system), disconnection of the link
between the radio and the IMMU will cause the radio to switch into the lock (``SECURE'') mode in which the
radio unit is fully inoperative. Hence, repair of the radio is basically impossible, unless the radio is reset to
the ``NEW'' state for which special decoding equipment is required.
Both Blaupunkt and Clarion have provided their authorized service representatives with so called ``decoder
boxes'' which can bring the radio unit back to the ``NEW'' state, enabling the radio to be switched on after
which repair can be carried out. Subsequently, when the repaired radio is delivered to the final user again,
it will be in the ``NEW'' state as to enable re-linking the radio to the vehicle's immobiliser system. As a result
of the above, repair of the radio can only be done by an authorized Blaupunkt or Clarion representative.
Note:
Radio manufacturer of Nissan D22 models for Europe is ``Clarion''.
SERVICE PROCEDURE
Item Service procedure Description
Battery disconnection No additional action required. Ð
Radio needs repair Repair needs to be done by authorized represen-
tative of radio manufacturer since radio cannot
be operated unless it is reset to NEW state,
using special decoding equipment.Ð
Replacement of radio by new
partNo additional action required. Radio is delivered in NEW state.
Transferring radio to another
vehicle/replacement of radio
by an ``old'' partRadio needs to be reset to NEW state by autho-
rized representative of radio manufacturer.Ð
AUDIO
EL-144

Item Service procedure Description
Replacement of IMMU by
new partNo additional action required. The new IMMU will be recognized by the radio
since a ``blank'' code is stored in the memory of
the IMMU. In case the radio recognizes this
`blank'' code, it will request for input of the cor-
rect CATS code after which the radio will switch
back to the initialisation process.
Replacement of IMMU by old
partRadio needs to be reset to NEW state by autho-
rized representative of radio manufacturer.If a radio code has already been stored in
memory of the IMMU, the radio cannot be linked
to it. After switching on the radio, it will display
``SECURE'' after 1 minute.
No communication from
IMMU to radio1. If NATS is malfunctioning, check NATS sys-
tem.
2. After NATS is repaired, reset radio to NEW
state by authorized representative of radio
manufacture.After switching on the radio, the radio will display
``SECURE'' after 1 minute. Further use of radios
impossible until communication is established
again, or after radio is reset by authorized repre-
sentative of (radio) manufacturer.
NOTE: Authorized radio manufacturer representatives in Europe are listed in the technical bulletin
TB-EL 96-001 issued by Nissan Europe N.V.
AUDIO
NATS Audio Link/For Europe LHD (KA24E)
(Cont'd)
EL-145

Component Parts and Harness Connector
Location
System Description
NATS has the following immobiliser functions:
lSince only NATS ignition keys, whose IDs. 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.
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.
lWhen NATS detects trouble, the malfunction indicator lamp (MIL) blinks.
lNATS 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.
lWhen servicing a malfunction of the NATS (indicated by flashing of Malfunction Indicator Lamp)
or registering another NATS ignition key ID no., it may be necessary to re-register original key
identification. Therefore, be sure to receive all keys from vehicle owner.
SEL649V
NATS (Nissan Anti-Theft System)/Gasoline engine for LHD models
EL-183

System Composition
The immobiliser function of the NATS consists of the following:
lNATS ignition key
lNATS immobiliser control unit (NATS IMMU) located in the ignition key cylinder
lEngine control module (ECM)
lNATS security indicator
lMalfunction indicator lamp (MIL)
SEL402V
NATS (Nissan Anti-Theft System)/Gasoline engine for LHD models
EL-184

CONSULT DIAGNOSTIC TEST MODE FUNCTION
CONSULT DIAGNOSTIC TEST
MODEDescription
C/U INITIALIZATION When replacing any of the following three components, C/U initialization is necessary.
[NATS ignition key/IMMU/ECM]
SELF-FUNCTION CHECK ECM checks its own NATS communication interface by itself.
SELF-DIAGNOSTIC RESULTS Detected items (screen terms) are as shown in the chart below.
NOTE:
When any initialisation is performed, all ID previously registered will be erased. So all NATS ignition
keys must be registered again.
The engine cannot be started with an unregistered key. In this case, the system may show ``DIFFER-
ENCE OF KEY'' or ``LOCK MODE'' as a self-diagnostic result on the CONSULT screen.
HOW TO READ SELF-DIAGNOSTIC RESULTS
NOTE:
lIf trip number is more than 1, MIL does not blink.
lTime data is not indicated for this model.
SELF-DIAGNOSTIC RESULTS ITEM CHART
Detected items (Screen terms) Description Reference page
IMMU ECM received the signal from IMMU that IMMU is malfunctioning. EL-190
ECM ECM is malfunctioning. EL-190
CHAIN OF ECM-IMMU Communication impossible between ECM and IMMU. EL-191
DIFFERENCE OF KEYIMMU can receive the key ID signal but the result of ID verification between key ID
and IMMU is NG.EL-193
CHAIN OF IMMU-KEY IMMU cannot receive the key ID signal. EL-194
ID DISCORD, IMM-ECMThe result of ID verification between IMMU and ECM is NG. System initialisation is
required.EL-194
MINGLE NOISENoise (interference) mingled into NATS communication lines during communicat-
ing.EL-195
DON'T ERASE BEFORE CHECKING
ENG DIAGEngine trouble data and NATS trouble data have been detected in ECM. EL-188
LOCK MODEWhen an unregistered ignition key is used, or if the starting operation is carried out
two or more times consecutively with the ignition key, IMMU or ECM
malfunctioning, NATS will shift the mode to one which prevents the engine from
being started.EL-196
SEL332UE
.Result display screen (When no malfunction is detected).Result display screen (When no malfunction is detected)
NATS (Nissan Anti-Theft System)/Gasoline engine for LHD models
CONSULT (Cont'd)
EL-187

SYMPTOM CHART
SYMPTOMDisplayed ``SELF-DIAG RESULTS''
on CONSULT screen.DIAGNOSTIC PROCEDURE
(Reference page)SYSTEM
(Malfunctioning part or mode)
lMIL blinkinglEngine will startIMMUPROCEDURE 1
(EL-190)IMMU
ECMPROCEDURE 2
(EL-190)ECM
lMIL blinkinglEngine does not startCHAIN OF ECM-IMMUPROCEDURE 3
(EL-191)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-193)Unregistered key
IMMU
CHAIN OF IMMU-KEYPROCEDURE 5
(EL-194)Malfunction of key ID chip
IMMU
ID DISCORD, IMM-ECMPROCEDURE 6
(EL-194)System initialisation has not yet
been completed.
ECM
IMMU
MINGLE NOISEPROCEDURE 7
(EL-195)Noise interference in communica-
tion line
LOCK MODEPROCEDURE 8
(EL-196)LOCK MODE
lMIL staying ONDON'T ERASE BEFORE CHECK-
ING ENG DIAGWORK FLOW
(EL-188)Engine trouble data and NATS
trouble data have been detected in
ECM.
lSecurity indicator does not oper-
ate properly.
lEngine starts properly.ÐPROCEDURE 9
(EL-197)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)/Gasoline engine for LHD models
Trouble Diagnoses (Cont'd)
EL-189

DIAGNOSTIC PROCEDURE 9
Security indicator check
CHECK INDICATOR CIRCUIT.
1. Disconnect NATS IMMU connector.
2. Check voltage between NATS IMMU
terminal
V6and ground.
Battery voltage should exist.
OK
cNG
Check the following.
l7.5A fuse (No.6,
located in the fuse block)
lSecurity indicator
lHarness for open or
short between fuse and
security indicator
lHarness for open or
short between NATS
IMMU and security indi-
cator
PERFORM INITIALISATION.
Perform initialisation with CONSULT.
For the initialisation procedure, refer to
``CONSULT operation manual NATS V2.0
(GASOLINE)''.
How to Replace NATS IMMU
NOTE:
lIf NATS IMMU is not installed correctly, NATS system
will not operate properly and SELF-DIAG RESULTS on
CONSULT screen will show ``LOCK MODE'' or ``CHAIN
OF IMMU-KEY''.
SEL400VC
SEL498V
.
NATS (Nissan Anti-Theft System)/Gasoline engine for LHD models
Trouble Diagnoses (Cont'd)
EL-197

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