AV-8
AUDIO
NATS AUDIO LINK
Description
The link with the NATS IMMU implies that the audio unit can basically only be operated if connected to the
matching NATS IMMU to which the audio unit was initially fitted on the production line.
Since radio operation is impossible after the link with the NATS is disrupted theft of the audio unit is basically
useless since special equipment is required to reset the audio unit.
Initialization process for audio units that are linked to the NATS IMMU
New audio units will be delivered to the factories in the “NEW” state, i.e. ready to be linked with the vehicle's
NATS. When the audio unit in “NEW” state is first switched on at the factory, it will start up communication with
the vehicle's immobilizer control unit (IMMU) and send a code (the “audio unit Code”) to the IMMU. The IMMU
will then store this code, which is unique to each audio unit, in its (permanent) memory.
Upon receipt of the code by the IMMU, the NATS will confirm correct receipt of the audio unit code to the audio
unit. Hereafter, the audio unit will operate as normal.
During the initialization process, “NEW” is displayed on the audio unit display. Normally though, communica-
tion between audio unit and IMMU takes such a short time (300 ms) that the audio unit seems to switch on
directly without showing “NEW” on its display.
Normal operation
Each time the audio unit is switched on afterwards, the audio unit code will be verified between the audio unit
and the NATS before the audio unit becomes operational. During the code verification process, “WAIT” is
shown on the audio unit display. Again, the communication takes such a short time (300 ms) that the audio
unit seems to switch on directly without showing “WAIT” on its display.
When the radio is locked
In case of a audio unit being linked with the vehicle's NATS (immobilizer system), disconnection of the link
between the audio unit and the IMMU will cause the audio unit to switch into the lock (“SECURE”) mode in
which the audio unit is fully inoperative. Hence, repair of the audio unit is basically impossible, unless the
audio unit is reset to the “NEW” state for which special decoding equipment is required.
Clarion has provided their authorized service representatives with so called “decoder boxes” which can bring
the audio unit back to the “NEW” state, enabling the audio unit to be switched on after which repair can be car-
ried out. Subsequently, when the repaired audio unit is delivered to the final user again, it will be in the “NEW”
state to enable re-linking the audio unit to the vehicle's immobilizer system. As a result of the above, repair of
the audio unit can only be done by an authorized Clarion representative (when the owner of the vehicle
requests repair and can show personal identification).
AUDIO
AV-9
C
D
E
F
G
H
I
J
L
MA
B
AV
Service Procedure
PERSONAL AUDIO SETTILNG
Description
The radio is designed to store several settings (volume, bass, treble, preset stations ) with every NATS
ignition key used. Up to a maximum of 4 NATS keys can be registered. During the communication men-
tioned under “Anti-Theft System”, the radio will recognize the used ignition key and select the accompany-
ing settings.
Item Service procedure Description
Battery disconnection No additional action required. —
Radio needs repair Repair needs to be done by authorized
representative of radio manufacturer since
radio cannot be operated unless it is reset
to NEW state, using special decoding
equipment.—
Replacement of radio by new part No 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
authorized representative of radio manu-
facturer.—
Replacement of IMMU Radio needs to be reset to NEW state by
authorized representative of Clarion.After switching on the radio, it will display
“SECURE” after 1 minute.
No communication from IMMU to radio 1. If NATS is malfunctioning, check NATS
system.
2. After NATS is repaired, reset radio to
NEW state by authorized representative
of Clarion.After switching on the radio, the radio will
display “SECURE” after 1 minute. Further
use of radio is impossible until communica-
tion is established again, or after radio is
reset by authorized representative of Clar-
ion.
When initialized between ECM and IMMU. Radio needs to be reset to NEW status by
authorized representative of Clarion.After switching on the radio, it will display
“SECURE” after 1 minute.
