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NOTE:
1.
Always warm the trailer's brakes before
setting the power. Warm trailer brakes tend
to be more responsive than cold brakes. To
warm trailer brakes, drive a short distance
(1/4 mile) at 45 MPH with manual lever
engaged enough to cause trailer braking at
a low level.
2.
WARNING The power should never be set
high enough to cause trailer brakes to lock
up. Skidding trailer wheels can cause loss of
directional stability of trailer and tow vehicle.
3.
The power may need to be adjusted for
different load weights and road conditions.
4.
Not all trailer brakes will lock up due to
various conditions. However, inability to
lock up the brakes generally indicates the
need for an inspection to determine the cause.
5.
When the power is set correctly you should
feel unified braking between the trailer and
tow vehicle.
6.
When in doubt of the proper setting
procedures review the above steps starting
at LEVELING THE SENSOR through FINE
TUNING or consult your tow card included
with your brake control.
Troubleshooting Chart
Situation
Tow vehicle connected to trailer,
NO GREEN light.
Tow vehicle connected to trailer, light is GREEN.
When Manual Slide Knob is activated:
A. No RED light.
B. Light is dim RED or flashing RED.
C. Light glows dim RED and gets brighter as
POWER Knob is decreased.
Braking with foot pedal is too aggressive.
Braking is delayed for extended period.
Tow vehicle connected to trailer, brake
pedal depressed:
A. No RED light.
Appendix A: Trailer Brake Adjustment**
Brakes should be adjusted after the first 200 miles of
operation when the brake shoes and drums have "seated"
and at 3000 mile intervals, or as use and performance requires.
The brakes should be adjusted in the following manner:
1.
Jack up trailer and secure on adequate capacity jack
stands. Follow trailer manufacturers recommendations for
lifting and supporting the unit. Check that the wheel and
drum rotate freely.
WARNING Do not lift or support trailer on any part of
the axle or the suspension system.
2.
Remove the adjusting hole cover from the adjusting slot
on the bottom of the brake backing plate.
3.
With a screwdriver or standard adjusting tool, rotate the
starwheel of the adjuster assembly to expand the brake
shoes. Adjust the brake shoes out until the pressure of
the linings against the drum makes the wheel very
difficult to turn.
Probable Cause
1. Corrosion on trailer plug contact.
2. Loose POWER or GROUND connection.
1. POWER set at or near minimum.
2. Short on BRAKE line (BLUE wire).
3. BLACK & WHITE wires reversed, control
destroyed.
4. 12 volts from external source on BRAKE
line (BLUE wire).
1. Open on GROUND line (WHITE wire).
2. Short on BRAKE line (BLUE wire).
1. Short on BRAKE line (BLUE wire).
2. Defective brake magnets.
1. Sensor set too aggressive, see LEVELING
SENSOR.
2. Power set too high.
1. Sensor set improperly, see LEVELING
SENSOR.
2. Power set too low.
1. Vehicle not moving, need to be moving for
brakes to apply.
2. No signal from brake light, test voltage on
RED wire.
3. Sensor set improperly, see LEVELING
SENSOR.
4. Bad connection on RED wire.
5. Blown stoplight fuse.
Note: With drop spindle axles, a modified adjusting tool
with about an 80 degree angle should be used.
4.
Then rotate the starwheel in the opposite direction until
the wheel turns freely with a slight lining drag.
5.
Replace the adjusting hole cover and lower the wheel
to the ground.
6.
Repeat the above procedure on all brakes.
WARNING Never crawl under your trailer unless it is
resting on properly placed jack stands.
Follow the trailer manufacturers recommendations for lifting
and supporting the unit. Do not lift or place supports on any
part of the suspension system.
**Note: Trailer Brake Adjustment procedures courtesy Dexter Axle.
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