Check Mcu And Osd For No Video Output - Mitsubishi Electric Diamond View 1995SL Service Manual

1995SL CRT Monitor Service Guide

7. Check MCU and OSD for no video output

Check F12M=12MHz CLOCK,ok?
(1)On the Main Board
(a) IC801 pin7
(2)IC1901 pin11 ~ pin18 output PWM ?
Check IC801 (BLANK)= "L",ok?
Check IC802 (EEPROM ),ok?
Check DCLK, DATA, ok?
(1) On the Main Board
(2) On the VIDEO Board
Check MCU and OSD
for no video output
Start
Use a preset timing
YES
Check +5V, ok ?
(1) On the Main Board,
(a) IC801 pin5
(b) IC802 pin8
(2) On the video Board,
IC1901 pin6,19
YES
YES
Check MCU (IC801)
Reset (pin4) = "H" to "L",ok?
YES
YES
YES
(a) SCL (IC801 pin 13)
(b) SDA (IC801 pin 14)
(a) SCL ( IC1901 pin 10)
(b) SDA ( IC1901 pin 9)
Chapter 4 Trouble Shooting
NO
Check +5V power
Check F12M CKT
on the Main Board .
NO
on video Board,
check OSD IC pin4 oscillation ?
NO Check
Reset circuit
NO Check
IC801 pin 1,12
NO
Check
(1) pin9 (ESDA)
(2) pin10 (ESCL)
(3) IC802 data
( EEPROM)
(Brightness, Contrast)
9