Brother KE-430B Service Manual page 185

Error status #1 The power indicator does not light when the power is turned on.
Probable causes
5. Power supply circuit board
defective
6. Main circuit board defective
7. Panel circuit board defective
Error status #2 Error code appears on the display window when the power is turned on.
Probable causes
1. Cooling fan defective when
the error code E-70 appears
on the display window.
([E.c1] KE-436B, 436C)
Check/ repair/ adjust
• Separate P4 (ACIN) connectors on the
power supply circuit board, and then
measure the resistance between the
following pairs of pins, pins 1 and 4 and
pins 2 and 4, in the connector on the
cable.
If the resistance is   in both cases, the
power supply circuit board is not defective.
• Measure the resistance between pins 1
and 2.
If there is no short, the power supply
circuit board is not defective.
• Rejoin P4 (ACIN) connectors on the
power supply circuit board.
Separate P9 (POWER) connectors on the
main circuit board, turn on the power, and
measure the voltage across pins 1 and 3
in the connector on the cable.
If it is + 5V, the power circuit board is not
defective.
After measurement, turn off the power,
wait at least 5 minutes, and then rejoin P9
connectors.
3634Q
• With P9 (POWER) connectors plugged in
on the main circuit board, turn on the
power, and measure the voltage across
pins 1 and 3 in the connector on the cable.
If it is + 5V, the power circuit board is not
defective.
After measurement, turn off the power.
3635Q
• Check that P8 (PANEL) connectors of the
main circuit board and P1 (PANEL)
connectors of the panel circuit board are
plugged in.
<KE-436B, 436C>
• Check that P20 (RSPORT) connectors of
the main circuit board and P5 (DRV)
connectors of the panel circuit board are
plugged in.
Check/ repair/ adjust
a. Check threads are not tangled in the
cooling fan.
b. Check P10
securely plugged in on the main circuit
board.
KE-430B, 430C series
(FAN) connectors are
8. ELECTRIC MECHANISM
Parts to be replaced
Power supply circuit
board
Main circuit board
Panel circuit board
Panel cord
Panel circuit board
Parts to be replaced
DC fan motor assembly
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