Service manual

R910E Service Manual
30
2. PANEL POWER CIRCUIT
3. INVERTER CONTROL RELATIVE CIRCUIT
Check R201 should have response
from 3.3V to 0V when we switch the
power switch from on to off
1.Measure U902/U905 PIN2=2.5V
U903/U904 PIN2=3.3V
2.
X600 oscillate waveform is normal
3. HS/VS input signals are normal
OK
Measure U203 Gate is low level?
Check U203 is broken or CN201
solder well?
OK
OK
NG
Replace U600
Check Correspondent
component.
NG
NG
Check Q201 is broken?
Replace Q201
OK
Replace Panel
Replace U203 or
re-solder CN201
NG
OK
NG
Check the BkLT_ON relative circuit, Q503
In normal operation, when LED =green,
Base of Q503 should be 0V,
If BkLT_ON no-response when the power
switch turn on-off, Replace U502 MCU
OK
Measured the inverter connector CN502
Pin5 on/off control=5V (on)
Pin7 PWM si
g
nal control dim 0V-5V
Replace Inverter board