System/Key Circuit - Zenith XBV613 - DVD/VCR Combination Service Manual

2. SYSTEM/KEY CIRCUIT

(1) AUTO STOP
Auto Stop
YES
Does the SW30 waveform
appear at IC501 Pin18?
YES
Do the T-UP Reel Pulses
appear at IC501 Pin80?
YES
Replace IC501.
(2) The unstable loading of a Cassette tape
The unstable loading of a
Cassette tape
YES
Is 12V applied to PMC01
Pin1?
YES
Does the "H" signal appear
at IC501 Pin60 during
inserting of the CST ?
YES
Does the "L" signal appear
at IC501 Pin19 during
inserting of the CST?
YES
Check the Deck
Mechanism.
Caution :
Auto stop can occur because Grease or Oil is dried up
NO
Check the Drum Motor
signal.
Do T/UP Reel Pulses
NO
appear at the point
between R556 and R536?
YES
Replace the T/UP Reel
Sensor (RS501).
NO
NO
Check the CST SW and
the peripheral circuitry.
NO
3-6
NO
Does 5V appear at RS501?
YES
Check the Q165 Power
Circuit.
Refer to "SMPS MOTOR_Vcc
12 Volt Trouble Shooting".
Is 5V applied to R531 ?
YES
Refer to SMPS 5.3VA
troubleshooting.
Check IC501 Pins22, 23,
24, 25.
NO
NO