Prism TM450 Installation Guide for JBus 1708 and 1939
Teletrac Inc.
1634-0300 00
Page 4
Main Power Connections
The system is designed to receive power and ground via the JBUS connector. Only the
Ignition wire is to be connected to a source of power. The ignition connection should be
made to a source of power other than the Accessory.
Alternate Power Input
In situations where the JBUS does not have power an alternate power input is supplied.
Disconnect the 3 PIN connector, located behind the DB15 JBUS Input, and connect the
External Power Harness (331-2022). While it is not very common, there will be trucks pre
2002 that only have Ignition power or simply no voltage at all.
