User's Manual

14221-1200-4010, Rev. B
52
The radios must have a solid and stable ground connection to vehicle ground. If there
is no well-grounded metal surface within approximately three (3) feet of the radios, a
metal grounding strap or a heavy-gauge wire (with proper wire terminals) must be
added between the metal surface and a solid and stable vehicle grounding point,
preferably near the battery. Some vehicles are equipped with a high-current DC
power access point (a vehicle option) that provides high-current power and ground
studs, typically in the vehicle’s trunk area. In this case, the ground stud of the power
access point can be considered a good vehicle ground, and used as such. Metal surfaces
should be stripped of all paint and dirt to expose bare metal before attaching a
grounding strap or wire terminal. To make all ground connections, the use of
stainless-steel hardware with machine-screw threads, shelf-locking nuts, and washers
is recommended.
4. Strip the area of any paint or dirt to expose a bare metal surface, approximately ¾-inch square.
5. Drill a hole in the approximate center of the bare metal surface, and deburr it.
A ⅜-inch non-insulated ring terminal is supplied with each cable to make the ground connection.
Therefore, hole diameter should be appropriate for the utilized grounding screw/bolt size and type
used to connect the ring terminals to the bare metal surface. This hardware is not supplied.
6. Cut the two (2) black wires to the required length plus some additional length for service loops in
each wire, then strip insulation back approximately ¼-inch.
7. Crimp a ⅜-inch non-insulated ring terminal (supplied with the cable) to the end of each black wire.
8. Attach the two (2) ring terminals with black wires to the bare metal surface using stainless-steel self-
locking hardware (i.e., machine screws with washers and locking nuts) or other appropriate hardware
to ensure a reliable terminal-to-metal contact. Tighten securely.
9. Apply an approved paint or rust-inhibitor over the remaining exposed bare metal surface and around
the ring terminal. Do not use an acid-based sealant.
9.2.1.2 Red Wires, Main Fuse Holder Connections (Radios’ Main Power Wires) and
CAN Cable
In a typical vehicle installation, the majority of the CAN cable between the remote-mount MRU radio and
the control head can be routed through the vehicle along with the two red wires of the radios’ DC power
cables. This is a time-saving measure. Also, any necessary option/accessory cables from the back of the
radio can also be routed with these wires and cable within the vehicle’s interior (i.e., up to but not through
the vehicle’s firewall).
The following installation procedure is recommended:
1. From the installation kit, get the CAN cable, part number CA-009562-030.
2. Remove interior panels, door kick panels, etc., as necessary to route the two red wires and the CAN
cable from the area of the remote-mount MRU radio (typically near the rear of the vehicle) to an area
near the vehicle’s firewall.