Aiwa HV-FX7800 Service Manual page 59

ELECTRICAL TROUBLESHOOTING -7/17
B.
Cassette tape loading is unstable.
Is REG 12V applied to IC502 Pin 7?
Is High signal applied to IC501 Pin 30
when inserting the CST?
Does Low signal occur form IC501 Pin 72
when inserting the CST?
Does 6.2V occur from IC502 Pin 2 when
inserting the CST?
Check the Deck Mechanism.
NOTE : Auto stop may also be caused by lack of lubrication,due to dried grease or oil.
C.
Non working function buttons.
Is the voltage of IC501 Pin 36, 5.2VA?
Does(Digitron) display change
when a function button is pressed?
Replace the defective switch.
YES
YES
YES
YES
YES
YES
Replace IC501.
NO
NO
Check the CST SW and
peripheral circuitry.
NO
NO
Change IC502 or ZD501(GDZJ 6.2C).
NO
NO
CHECK IC5F1
(IC5F1 PIN 15~30, PIN36~44 pulse
output)
YES
-59-
Check the power.
Is 5.3V applied to R544?
YES
Check the power.
Check IC501 Pins 68, 69, 70, 71.
Check the power.
Replace IC5F1
NO
NO