Airstream 2001 Bamby, Owner'S Manual

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AIRSTREAM SAFARI –BAMBI TRAILER OWNERS MANUAL 2001
D-14
SHOES AND LININGS
A simple visual inspection of your brake linings will tell if they are usable. Replacement is necessary if the lining is
worn thin (1/16" or less), contaminated with grease or oil, or abnormally scored or gouged. It is important to replace
both shoes on each brake and both brakes of the same axle. This is necessary to retain the "balance" of your brakes.
Noted below are the Dexter replacement shoe and lining kits, which will contain the specific instructions necessary
for proper replacement.
TROUBLE SHOOTING
Most brake malfunctions that cannot be corrected by either brake adjustment or synchronization adjustments can
generally be traced to electrical system failures. Mechanical causes are ordinarily obvious, i.e. bent or broken parts,
worn out linings or magnets, seized lever arms or shoes, scored drums, loose parts, etc. Electrically, a voltmeter and
ammeter are essential for proper troubleshooting
HOW TO MEASURE VOLTAGE
System voltage is measured at the magnets by connecting the voltmeter to the two magnet lead wires at any brake.
This may be accomplished by using a pin probe inserted through the insulation of the wires dropping down from the
chassis or by cutting the wires. The engine of the towing vehicle should be running when checking the voltage so
that low batteries will not affect the readings.
Voltage in the system should begin at 0 volts and, as the controller bar is slowly actuated, should gradually increase
to about 12 volts. This is referred to as modulation. No modulation means that when the controller begins to apply
voltage to the brakes it applies an immediate high voltage, which causes the brakes to apply instantaneous maximum
power.
The threshold voltage of a controller is the
voltage applied to the brakes when the
controller first turns on. The lower the
threshold voltage the smoother the brakes
will operate. Too high of a threshold
voltage (in excess of 2 volts as quite often
found in heavy duty controllers) can cause
grabby harsh brakes.
HOW TO MEASURE AMPERAGE
System amperage is the amperage being
drawn by all brakes on the trailer. The
engine of the towing vehicle should be
running when checking amperage. One
place to measure system amperage is at the
BLUE wire of the controller, which is the output to the brakes. The BLUE wire must be disconnected and the
ammeter put into the line. System amperage draw should be as noted in the table following. Make sure your
ammeter has sufficient capacity and note polarity to prevent damaging your ammeter. If a resistor is used in the
brake system it must be set at zero or by-passed completely to obtain the maximum amperage reading.