RAMHD-230/734
Installation and Operation Manual
PG 36/41
REV: B (4/8/2021)
10.
On-Vehicle Electrical Installation
10.1.
Disconnect Vehicle Battery(s)
CAUTION:
Follow all recommended safety precautions for working on vehicle
’s
electrical system; consult
vehicle owner’s manual for further instr
uction.
10.2.
Attach Relay to Vehicle
a.
The supplied relay is pre-wired so that it can be installed in line with main power wire. Before cutting
any wires, determine adequate placement of relay, and wire accordingly.
i.
Under hood near battery is always recommended, but final placement is at discretion of end
user.
ii.
Mount relay to vehicle using supplied self-tapping screws.
b.
Connect
Pin #87 to compressor’s Red power wire, using
supplied large Yellow female crimp connector.
Wire should be routed down passenger side frame rail away from all exhaust, for later connection to
compressor.
c.
Connect Pin #85 to supplied 18-gauge black wire (12-18 inches in length), and attach to adequate
vehicle, or chassis ground, using supplied small blue ring terminal and self-tapping screw.
d.
Connect Pin #86 to supplied Yellow wire and route to pressure switch wire on Air Tank (either wire can
be connected). Connect remaining yellow wire to other wire on pressure switch, route to vehicle
interior, and connect it to a fused, 12v switched power source (i.e., open accessory spot on fuse block).
10.3.
Route Wiring and Install Horn Button
a.
Locate red 10-gauge power wire, this wire will be run to battery and down to compressor bracket. Wire
should be routed down passenger side frame rail away from all exhaust, for later connection to
compressor; however, installer may route as desired.
i.
Install supplied fuse holder on end of power wire by cutting the loop in fuse holder and
connecting supplied Ring terminal to one end and butt connector on other end. Connect butt
connector to red power wire and crimp properly.
CAUTION:
Do not install 30-amp fuse provided until all electrical connections are final.
ii.
Connect ring terminal to positive terminal of battery; if multiple batteries exist on vehicle,
it’s
recommended to attach to secondary battery.
iii.
Route wire through 1/4” supplied split l
oom.
NOTE: Do not cut wires to length until you are 100% sure of length required for final connections.
b.
Route yellow and purple wires from horn and ignition switch through a grommet in cab floor; user
preference on grommet to use, based on selected route of wiring.
c.
Find a suitable location for horn pushbutton (i.e., in dash, center console, etc.)
and drill a 3/4” hole. Run
purple wire from behind and through hole along with supplied section of 18-gauge red wire. Slide
