Motorola iDEN i500plus Owner's Manual page 7

Junction Box Installation Instruction
In most vehicles, the best location for mounting the junction box is just
under the dash, or under the front seat. It must be protected from dirt and
moisture, and must be afforded adequate space for cooling. There must
also be sufficient space to allow for the connection of accessories. Mount
the junction box using the provided screws.
Visor Mic
PTT
External Speaker
Figure 3. Junction Box - Accessories Connection Diagram
CAR KIT OWNER'S MANUAL
Phone Cradle
Palm Mic
Power Cable
DB9, RS-232
Data Cable
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