Cpu Fan Does Not Work; Indicator Does Not Light. ("Welcome" Does Not Light At Startup.) - Toshiba HD-XA2KN Service Manual

3-3.

CPU FAN does not work.

START (3)
Pin 1 of CN803 develope
12V±5%?
Power circuit
troubleshooting
3-4.

Indicator does not light. ("WELCOME" does not light at startup.)

START (4)
Pin 1~4 of IC705 VFD
driver IF bus working
at startup?
1: CLK
2: DIN
3: STB
4: DOUT
Failure of main unit
Yes
No
Yes
No
Replace FAN unit.
PIN 20 of CN601
develope 5V±5%?
No
Power circuit troubleshooting
Yes
Replace front FIP
unit or main unit.