4.To check for open circuits, slowly move the test lead in the direction that the open circuit seems to exist. Try to find
a point where a voltage is generated or changes to 0V. The point where the voltage has changed is the open-
circuit point.
5.Use an ohmmeter to measure the resistance of each heater line between a terminal and the center of a grid line,
and between the same terminal and the center of one adjacent heater line. The section with a broken heater line
will have a resistance twice as that in other sections. In the affected section, move the test lead to a position where
the resistance sharply changes.
REPAIR OF BROKEN HEATER LINE
Prepare the following items:
1. Conductive paint.
2. Paint thinner.
3. Masking tape.
4. Silicone remover.
5. Using a thin brush :
Wipe the glass adjacent to the broken heater line, clean with silicone remover and attach the masking tape as
shown. Shake the conductive paint container well, and apply three coats with a brush at intervals of about 15
minutes apart. Remove the tape and allow sufficient time for drying before applying power. For a better finish,
scrape away excess deposits with a knife after the paint has completely dried. (Allow 24 hours).
