Troubleshooting - Samsung CKA4217L Service Manual

6 Troubleshooting

Notes: 1. If a picture does not appear, fully rotate the brightness and contrast controls clockwise and reinspect.
2. Check the following circuits.
• No raster appears: Power circuit, Horizontal output circuit, H/V control circuit, and H/V output circuit.
• High voltage develops but no raster appears: Video output circuits.
• High voltage does not develop: Horizontal output circuits.
6-1 No Power
Does proper AC 90-264 Volts
appear between the positive and
negative poles of C604?
Yes
Check D604~D607, D609, IC602,
T601, OP601, and power circuit.
6-2 Horizontal Line on CRT
Does DC 13 V appear at
Pin 2 of IC301?
Yes
Does DC -11 V appear at
Pin 4 of IC301?
Yes
Does the output pulse of
48 Vp-p appear
17
at Pin 5 of IC301?
Yes
Check IC301 and its
related circuits
CKA42*7L/5227L
No
Check F601, L602 and TH602.
No
Check the power supply circuits
(D616)
No
Check the power supply circuits
(D608)
Replace IC301 or check its
No
related circuits
(D301, IC301 and R312)
WAVEFORMS
17 45.0 V (IC301, #5)
CH1 P-P = 45.0 V CH1 RMS = 5.48 V
6-1