NPM-2NX
Car Kit
CCS Technical Documentation
Page 8
ã
Nokia Corporation
Issue 1 07/02
tion. This feature is convenient and provides for safer handsfree operation. The car radio
muting feature is based on a grounded line, so it means that in standby, the yellow wire
(XCRM) is not grounded and car radio works normally, but during a call, line is grounded
and car radio is muted. Note that an auxiliary relay or muting unit must be used when
the car radio does not have a mute feature available.
When a relay is used, connect of series with the car radio main supply. A 200 mA fuse
should be used to protect the XCRM output in event of a short circuit. Some radios have
separate supplies for amplifiers and motors, and another for memory backup purposes.
Very often these radios also have a secret code system, which activates itself if a break in
the memory supply is detected. Be careful when installing the relay not to break the
memory supply (usually marked ACC or +MEM), but to install the relay in the main sup-
ply feed.
Figure 4: Car Radio Muting CRM
Another possibility is to use a special muting unit, which mutes the radio by connecting
load resistors to the speaker lines of the car radio.
Antenna Motor Control AMC
The antenna motor control offers a feature, green wire of the system cable (AMC), that
may be used to control different devices on and off. The voltage in this output is +12 V
whenever the phone is on. If the phone is turned off, the voltage disappears. The maxi-
mum output current is 200 mA; therefore, for example, motorized antenna must be con-
trolled via a relay (see diagram below).
Figure 5: Antenna Motor Control AMC
All installations should take into account any special requirements of the customer.
However, should the customer require an installation that is illegal or unsafe, these facts
CAR
RADIO
Bosch P/N 0–332–204–150
12 V, 30 A. SPDT
12 V d.c.
12 V d.c.
Supply for
car radio
Fuse 200 mA
(not supplied)
To XCRM line
(yellow wire)
85
87
87A
30
86
GND
87
Bosch P/N 0–332–204–150 12 V, 30 A.
SPDT
12 V d.c.
Fuse 1 A
85
87A
30
86
GND
CONTROLLED
DEVICE e.g.
MOTOR ANTENNA
GND
Supply for device
From AMC line (green
wire)
