Chrysler 300M 2002 Service Manual page 1728

an active code; active codes automatically erase by
themselves when the reason for the code has been
corrected.
With the exception of the warning lamp trouble
codes or malfunctions, when a malfunction is de-
tected, the airbag lamp remains lit for a minimum
of 12 seconds or as long as the malfunction is
present.
An ''Interrogate Right SIACM or Interrogate Left
SIACM'' diagnostic trouble code indicates an active
trouble code in the respective module.
3.1.7.2 STORED CODES
Airbag codes are automatically stored in the
ACM's memory as soon as the malfunction is de-
tected. A "stored" code indicates there was an active
code present at some time. However, the code cur-
rently may not be present as an active code, al-
though another active code could be.
When a trouble code occurs, the airbag warning
lamp illuminates for 12 seconds minimum (even if
the problem existed for less than 12 seconds). The
code is stored, along with the time in minutes it was
active, and the number of times the ignition has
been cycled since the problem was last detected.
The minimum time shown for any code will be one
minute, even if the code was actually present for
less than one minute. Thus, the time shown for a
code that was present for two minutes 13 seconds,
for example, would be three minutes.
If a malfunction is detected a diagnostic trouble
code is stored and will remain stored as long as the
malfunction exists. When and if the malfunction
ceases to exist, an ignition cycle count will be
initiated for that code. If the ignition cycle count
reaches 100 without a reoccurrence of the same
malfunction, the diagnostic trouble code is erased
and that ignition cycle counter is reset to zero. If the
malfunction reoccurs before the count reaches 100,
then the ignition cycle counter will be reset and the
diagnostic trouble code will continue to be a stored
code.
Maintain a safe distance from all airbags while
performing the following inspection. If a malfunc-
tion is not active while performing a diagnostic test
procedure, the active code diagnostic test will not
locate the source of the problem. In this case, the
stored code can indicate an area to inspect.
If no obvious problems are found, erase stored
codes, and with the ignition "on" wiggle the wire
harness and connectors, rotate the steering wheel
from stop to stop. Recheck for codes periodically as
you work through the system. This procedure may
uncover a malfunction that is difficult to locate.
GENERAL INFORMATION
3.2 AUDIO SYSTEM
There are radio systems available that communi-
cate on the PCI bus. They use the bus for three
reasons. First is to communicate trouble codes,
second is to control the remote radio switches lo-
cated on the back of the steering wheel, and third is
for use with the driver memory selection system.
The radio stores two sets of station presets and can
be recalled by pressing the optional memory select
button (located on the drivers door). The midline
will have 6 speakers and a 120 watt external
amplifier. The Infinity I will have 7 speakers and a
240 watt external amplifier or with a indash 4-disk
CD Player. The Infinity II will have 9 speakers and
a 360 watt external amplifier with a indash 4-disk
CD Player.
When troubleshooting output shorts or ''output''
error messages, the following applies:
On radios with out an external amplifier, the
term output refers to the path between the radio
and the speaker. This type of circuit can be moni-
tored all the way through the speaker connections
by the radio assembly. When the radio displays a
shorted output DTC with this type of system, the
speaker, radio, or wiring could be at fault.
On radios with an external amplifier, the term
''output'' refers to the circuit between the radio
connector and the amplifier. The radio is capable of
monitoring only this portion and can tell nothing
about the circuit between the amplifier and the
speakers. Consequently, a shorted output DTC on
this type of system would only refer to this circuit.
A faulty speaker could not cause this DTC.
These radios can be controlled via remote radio
switches (optional). These switches are located on
the back side of the steering wheel. They control
volume, preset bank selection, seek and scan func-
tions.
These functions are inputs to the body controller
and can be read with the DRBIII under ''body''
systems, sensor displays. The switches are a multi-
plexed signal to the BCM. The remote radio control
circuit is a five volt line that is pulled to ground
through different value resistors built into the
switches. This causes a voltage drop to be seen by
the body controller and it sends a specific message
to the radio on the PCI bus line. The radio then
responds to the message.
This circuit is fairly simple to troubleshoot. The
circuit must be complete from the switches in the
steering wheel to the BCM. The ground must be
complete so that the switches can cause the voltage
drop for the BCM to see. The circuit passes through
the clockspring so continuity throught this device
must be verified.
The new in-dash CD-changer is designed to fit
into the existing cubby bin in the center stack. This
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