AUDIO
AV-3
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AV
AUDIOPFP:28111
System DescriptionEKS002F2
Refer to Owner's Manual for audio system operating instructions.
Power is supplied at all times
●to audio unit terminal 3 and
●to CD auto changer terminal 32
●through 15A fuse (No. 32, located in the fuse and fusible link box).
With the ignition switch in the ACC or ON position, power is supplied
●to audio unit terminal 6 and
●to CD auto changer terminal 36
●through 10A fuse [No. 4, located in the fuse block (J/B)]
Ground is supplied through the case of the audio unit.
Audio signals are supplied
●through audio unit terminals 5, 7, 9, 10, 11, 13, 15, 16
●to terminals 1 and 2 of front door speaker LH and RH,
●to terminals 1 and 2 of rear door speaker LH and RH and
●to terminals 1 and 2 of tweeter LH and RH (with 6-speakers)
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 NAT S I M M U
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).
