Toshiba 1997 G Series Troubleshooting Manual page 11

Check: Sub Power supply, Microprocessor
and Relay drive circuits
Open pin 3&4
Open fuse F470
Main B+ is below
150V. Freq. at pin 14
if IC801 is above 60Hz.
Open pin 3
of Q862
Problem is in primary side of power supply.
Recommended circuit checks: IC 801,
Over Current protect and Oscillator
Power Supply Troubleshooting Guide.
No
Does the relay engage?
B+ to low
of Q862
If 165V and Start up
are present.
Problem is in primary side of power supply.
Recommended circuit checks: IC 801,
Over Current protect, Oscillator, Latch Delay,
LC Resonance, DriveCircuit, and Pre amp.
Main B+ goes to 155+ then
to 0v Relay stays on. Frquency at
pin 14 of IC801 is 60Hz
Problem in the feedback loop.
Recommended checks: Z801,
and Q862
Push power button
Yes
0V
Is the B+ at F470
Low or at 0v?
Check start up voltage and 165V on IC 801.
If missing Check F860, D801 SR81 and
surrounding compnonets.
Main B+ is 140V
150V. Freq. at pin 14
if IC801 is 136KHz.
Problem is in the load.
Main B+ is 140V
150V. Freq. at pin 14
if IC801 is 138KHz.
9
No
Does the TV go into
shutdown?
Main B+ reaches 155+ the
to 0v Relay stays on.
Frquency at pin 14 of IC80
is 60Hz
Open F470
Main B+ goes to 155+ then
to 0v Relay stays on. Frquency at
pin 14 of IC801 is 60Hz
Short pins 3&4
of Q862
Problem is in primary side of power supply.
Recommended circuit checks: IC 801, and
Oscillator
Yes