Brother PE-180D Service Manual page 37

ELECTRICAL SYSTEMS TROUBLESHOOTING
* When measuring resistance, always turn the power off and disconnect the connector to be measured
from the circuit board before taking the measurement.
* Refer to the figures for where to check.
CONDITION
1. Power is ON 1) When the power switch is ON, is the
but the buzzer
does not sound
and nothing is
2) Disconnect the output connector (CN1)
displayed in the
LCD.
3) Is the fuse blown?
4) Other
2. Pulse motors 1) Is there the normal resistance between
do not correctly
detect the
home position
after the power
is turned on
and the needle
2) The pulse motor only detects the home
is in the up
position.
3) Is the fuse blown?
4) Disconnect the output connector (CN1)
5) X or Y pulse motor will not stop seeking
6) Other
PROBLEM SYMPTOMS
resistance between both ends less than
1 Ω?
from the power supply PC board; is the
voltage between terminals 1-2, and 3-4
normal?
Between 1-2 ......................24 to 31 V DC
Between 3-4 ......................13 to 18 V DC
the following pins of the connector of the
pulse motor that does not detect the
home position?
X (CN16)....Between 1-2, 3-4 → Approx.Ω
Y (CN17)....Between 1-2, 3-4 → Approx.Ω
position regardless of the needle position.
from the power supply PC board; is the
voltage between 1-2 normal?
Between 1-2 ......................24 to 31 V DC
the home position.
1) Replace the power supply unit assembly.
2) Replace the power supply unit assembly.
3) Replace the fuse (after correcting the
cause of the blown fuse).
4) Replace the main PC board assembly.
1) Replace the defective pulse motor.
2) Replace the NP PC board assembly.
3) Replace the fuse (after correcting the
cause of the blown fuse).
4) Replace the power supply unit assembly.
5) Replace the X sensor PC board
assembly or the Y sensor PC board
assembly.
6) Replace the main PC board assembly.
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COUNTERMEASURES