Roadmaster 98300 Installation Instructions Manual - Wire The Proportioning Valve
Wire the proportioning valve
The solenoid valve (Figure 9) on the proportioning
valve allows air to pass into the BrakeMaster system
each time the motorhome’s brake pedal is depressed.
The solenoid valve will allow air to pass only when it
receives an electrical signal from the motorhome brake
light system.
Where you connect the solenoid valve to the motor-
home depends upon the type of brake light system in
the motorhome. Compare the motorhome’s brake and
turn lights to Figures 12 and 13.
1. If the motorhome has a separate brake and turn
signal system (Figure 12), connect the remaining
black wire extending from the solenoid valve to the
motorhome’s brake light wire. The brake light wire can
usually be located in the wiring harness that runs along
the frame; the connection can be made at any conve-
nient point.
Refer to the inside front cover for a wiring schematic.
2. If the motorhome has a combined brake and turn
signal system (Figure 13), attach the included butt con-
nector to the end of the remaining wire extending from
the solenoid valve, and attach the length of included
wire to the other end of the butt connector.
Route the wire from the solenoid valve to the brake
light wire, under the dashboard of the motorhome. With
a test light, find the “cold” side of the brake light switch
— the “cold” side of the switch does not register voltage
unless the brakes are applied. With a 12-volt meter,
verify that you have found 12 VDC+.
Cut the brake light wire, a few inches downstream
from the “cold” side of the brake light switch. Cut the
wire from the solenoid valve to length, then attach it to
the brake light wire with another butt connector.
Refer to the inside front cover for a wiring schematic.
Ensure that the wire will not present an obstacle
or hazard to the motorhome driver, or interfere with
the operation of the vehicle. Use one or more of the
included wire ties, if necessary, to secure the wire out
of the way.
Note: connect the wire from the solenoid valve to the
brake light wire before the turn signal switch (located
in the steering column). If the wire is connected after
the turn signal switch, BrakeMaster will not function
properly.
Figure 12
Figure 13
12