Factory Cat MINI-MAG SERIES Service Manual page 105

"BRUSH PRESSURE"
switch does not work.
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?
Replace the
controller
NO
Is there
between 0.8 and
2.8 volts?
YES
YES
Repair open circuit between
the controller and the switch.
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?
Mini-Mag Service Manual V1.0
MiniMAG – TRACTION DRIVE w/CCII
BRUSH PRESSURE SWITCH DIAGNOSIS
1 of 2
Operate machine
and verify the
customers
complaint.
Repair open circuit
YES
to switch
At the 20 pin Molex
connector at the
controller, back
probe pin # 2 with
the positive probe
of the meter.
NO
NO
FROM
PAGE 2
"B"
CENTRAL COMMAND CONTROLLER
Does the switch
work properly?
NO
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
the voltage at the center tab of the
brush pressure switch. (yellow wire)
Was there
between 0.8 and
2.8 volts?
NO
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?
YES
GO TO
PAGE 2
"A"
Instruct owner on
YES proper machine
operation
13-27
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