TERION UM20-100111B, Installation Manual, Page: 26 / 78

Note: When applying Loctite, only a small amount is required.
12. Apply a small amount of Loctite 242, or similar locking compound, to the threads that
will be covered by the stud mount nut when it is fully tightened.
13. Tighten the stud mount nut finger tight, and then use a wrench to tighten it another
3/4 turn to 1 turn . This should result in a torque of approximately 10 foot-pounds.
14. Verify the resistance from the antenna mount to the frame rail is less than 1 ohm.
Note: For this measurement, make sure the power is not plugged
into the ITU, and the coax cable is not connected to the antenna.
The truck must be off, and everything using the truck's batteries
must be off (e.g., turn off lights, keep the doors closed so the cab
light does not come on, turn off any appliances like refrigerators,
etc.).
15. Place a bead of dielectric silicone grease (clear grease) around the base of the antenna
stud mount where the upper portion of the coaxial cable connector will be connected.
Leave the last three to four threads clean. This will prevent moisture from getting
into the assembly and still maintain good metal-to-metal contact with at least three
threads.
Note: The easiest way to determine where the upper part of the
connector will be connected is to connect it and examine how high
on the stud mount the connector sits. Don't use too much silicone
grease.
16. Attach the FM-DHF coaxial cable to the antenna stud mount and tighten the
connection.
17. Determine the best place for the coax cable to enter the truck cab. The cables should
enter through the fender near the antenna base mount. Drill the cable entry hole,
starting the hole with a center punch, drilling a 1/8" pilot hole, and then drilling a 3/4"
hole. Use a de-burring tool to smooth the edges of the hole.
18. Pass the coaxial cable through the hole. Place a 3/4" grommet around the cable and
into the entry hole.
Note: If the GPS antenna cable can share the entry hole, then place the GPS
antenna cable through the hole along with the FM/DHF antenna cable.
Note: Use the grommet most appropriate for the wall thickness; the
installation kit comes with two grommet sizes for either a 1/16" or a 1/8" wall
thickness.
19. Guide the top end of the antenna through the antenna upper support bracket. Install a
split lock washer onto the stud, and then fasten the antenna to the stud mount
assembly. Use wrenches to tighten the connection.
20. Now that the antenna is aligned between the mount and the upper support, complete
tightening the bolts on the antenna base mount bracket.
4-10
Mobile Messaging System Installation Manual June 15, 2001
UM20-100111B Terion, Inc.