R.P.S. Corporation MAGNUM series, Service Manual

Page: 88 / 134

Magnum Service Manual V1.0
13
13-10
COMPUTER CONTROL SYSTEM
“BRUSH PRESSURE”
switch does not work.
Operate machine
and verify the
customers
complaint.
Does the switch
work properly?
Instruct owner on
proper machine
operation
YES
Using voltmeter set the meter to DC
volts. Connect the ( -) probe of the
meter to the ( - ) buss bar with a clip on
your meter probe. Measure at the
center tab of the brush pressure switch.
(yellow wire)
Was there
between 0.8 and
2.8 volts?
NO
At the 20 pin Molex
connector at the
controller, back
probe pin # 2 with
the positive probe
of the meter.
Is there
between 0.8 and
2.8 volts?
Replace the
controller
NO
NO
YES
YES
Place the ( + ) probe
back on the center
terminal of the switch.
yellow wire) Move the
switch up and measure
the voltage.
Did the voltage of the
terminal raise to between 4.8
and 5.2 volts when the switch
was moved up?
Place your meters ( + )
probe on the lower
terminal of the switch.
(red wires) Measure the
voltage
Was the voltage
between 4.8 and 5.2
volts?
YES
NO
Repair open circuit between
the controller and the switch.
YES
At the 20 pin Molex connector
at the controller, back probe
pin #16 with the positive probe
of the meter.
Is there
between 4.8 and
5.2 volts?
Repair open circuit
to switch
YES
MAGNUM BRUSH PRESSURE SWITCH DIAGNOSTIC FLOW CHART
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