TROUBLE SHOOTING
1. POWER
≧ 1.4V
1.1. The unit does not power on
YES
YES
NO
YES
NO
YES
NO
NO
Does the power indicator on the front panel
flash in green or white when the power is turned
on?
Is a fuse blown?
Does the power display on the front panel lights
green or white after approximately 8 seconds?
Check the voltage of pins 1, 5 of CN761 on the
DIGITAL PCB while the power display is flashing
in green or white.
Check the voltage of pins 7 of CN761 on the
DIGITAL PCB while the power display is flashing
in green or white.
Remove the connector (BN501) of the MAIN PCB.
Check the "
3-2. Protection History Display Mode
"
The unit does not power on
Is a fuse blown?
Does the power indicator on the front
panel flash in red when the power is turned
on?
Is DC 5.2V being supplied from the SMPS PCB
(BN601) to the DIGITAL PCB?
See "
See "
"
Check the circuits around the Microprocessor
on the DIGITAL PCB and replace any faulty
parts.
TO "
Are there any parts not fully connected into
the connectors that connect the PCBs?
Is DC 5.2V output even when the board in wire
(BN601) supplying power from the SMPS PCB
to the DIGITAL PCB is removed?
Check the circuits around the Microprocessor
on the DIGITAL PCB and replace any faulty
parts.
Check for breakages and short circuits in the
circuits and parts between CN741 on the DIGI-
TAL PCB and the microprocessor power supply
and replace any faulty parts.
Connect the connectors correctly.
"
YES
Check for leaks and short
circuits in the parts on the pri-
mary side. Replace any faulty
parts.
Blown fuse
Check the rectifier diode in the
rectifier circuit on the second-
ary side, and check for short
circuits. Replace any faulty
parts.
Replace the fuse after repair.
Check for short circuits between
the regulator output terminal and
GND in the power supply stabiliza-
tion circuit. Replace faulty parts if
there is a short circuit.
1.2. Fuse is blown
NO
NO
NO
YES
YES
0V
3.3V
0V
NO
YES
61
Caution in
servicing
Electrical
Mechanical
Repair Information
Updating
