MM-007024-001
38
below.
The Control Head’s DC Power Cable and associated fuse and wire terminal devices are shown in
Figure 9-4.
NOTE
Only the Control Head’s white wire and the Time-Delay Relay’s white wire must be
connected to the ignition or switched power sense. When this vehicle line is asserted (i.e.,
power switched on), the Control Head automatically powers-up the radio via the CAN
connection.
Figure 9-4: Connection of White Ignition Sense Wire
9.5.3.1
Control Head and Radio Turn on with Vehicle’s Ignition Switch/Key
With this wiring configuration, the Control Head and radio automatically turn on and off with the
vehicle’s ignition switch/key. The white wire of the Control Head’s DC Power Cable is typically
identified as the “white ignition switch wire” or the “ignition sense wire.” In this configuration, the white
wire connects to a switched power source, typically identified as “Accessory” power, that switches on and
off with the vehicle’s ignition switch/key.
NOTE
The white ignition sense wire must be connected to a fused power source that switches
from approximately zero volts to approxi13.6 volts when the vehicle’s ignition
switch/key is turned from the OFF position to the ACCESSORY and RUN positions.
Use of a switched power source that is subject to voltage changes as a result of other
actions, such as opening a vehicle door, may result in undesirable radio operation and/or
a degradation of radio performance.
1.
Locate the switched ignition or “Accessory” power wire (typically at or near the vehicle’s fuse block
or in a vehicle wiring harness) that will be used for the switched ignition power source. It may be
necessary to consult the vehicle manufacturer’s wiring diagram.