PW
1. Pull the 130v line fuse and see if the power supply comes up and
regulates at 130 volts.
If it is then the power supply is 99% for sure ok. Reinstall the fuse.
2. Ground the positive of c474 on the protect module, per the service
manual.
This will rule it out if the set comes up properly. Unground the
capacitor.
3. On the convergence board you will find a 3 pin plug, on of them is
protect line, pull the plug and remove the protect wire. If the set
comes up you have a failure in the convergence circuit. If it does come
up and stay up, some resistors may start to burn on the convergence board,
unplug the tv before they go up in smoke.
4. Physically pull all the yokes off the picture tubes and make sure they
are not burnt, if one of them is, that crt probably is also damaged. VERY
COMMON. If you need to replace the crt, make sure you order the high
voltage lead and high voltage silicon from Toshiba. Affix the lead to the
tube and wait 2 full days before putting in the set and powering up. It
must be 100% cured before appplying the high voltage.
5. Pull the DPC board and unsolder the protect line. This can be risky so
be prepared to unplug the tv ASAP. Have seen a 180k resistor increase in
value and cause dead/ intermittent dead set problems.
6. Pull all the high voltage wires to the crt's out of the hv block. If
set runs, install one at a time with the set off to find which crt is bad.
7. As a last resort, ground the anode of each of the remaining diodes on
the protect line, of course with the high voltage leads to the crt's
disconnected. To find which circuit has the problem.
David