Samsung CKF5607 Troubleshooting
CKF5607L 7-1
7 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.
7-1 No Power
Check Fuse, D600, D602, D603
and D604.
Does proper AC 90-264 Volts
appear between the positive and
negative poles of C606?
Yes
No
Check D608, D609, D610, D611,
D612 and T601.
PWM output appear at Pin 5
of T601?
Yes
No
Check T602 and D608.
Check Power protection.
Check IC602.
AFC Signal appear at
negative pole of C612?
Yes
No
Check D615.
Check IC602.
H-Sync Pulse appear at Pin
5 of IC602?
Yes
No
VCC appear at Pin 3 of IC602?
Yes
No
WAVEFORMS
3
4
472V (T601 #5)
CH1 P-P = 472 V CH1 RMS = 372.2 V
3
3.44 V (C612, –)
CH1 P-P = 3.44 V CH1 RMS = 620 mV
4
7 Troubleshooting
7-2 CKF5607L
7-3 Vertical Line on CRT (Root Cause : Horizontal Deflection Parts Fail)
Check 5V,
12V Line.
Check IC401.
Does PWM output signal appear
at Pin 26 (H-out) of IC401?
Yes
No
Does DC 5 V appear at Pin 32
of IC401?
Yes
No
Check Q403 and Q404.
Check Q405.
Does 12Vp-p signal appear at
Emitters of Q403 and Q404?
Yes
No
No
Check CN401, CN402, D409
and Q410
Does 120Vp-p signal appear at
Pin 1 of T401?
Yes
Check swap IC300.
Check connector CN300 and CN301.
Check CN300 and CN301.
Check DC 13 V Line.
7-2 Horizontal Line on CRT (Root Cause : Vertical Deflection Parts Fail)
Does output pulse of 50Vp-p
appear at Pin 5 of IC301?
Does rectangular signal output
at Pin 5 of IC300?
Yes
No
No
Does DC 13 V appear at Pin 2
of IC300?
Yes
Yes
No
Check DC –12 V Line.
Does DC -12 V appear at Pin 4 of
IC300?
Yes
No
WAVEFORMS
18
6
11
WAVEFORMS
43.0 V (IC300 #5)
CH1 P-P = 43.0 V CH1 RMS = 5.34 V
18
9.24 V (IC401, #26)
CH1 P-P = 9.24 V CH1 RMS = 6.048 V
6
93.6 V (T401, #1)
CH1 P-P = 93.6 V CH1 RMS = 55.2 V
11
7 Troubleshooting
CKF5607L 7-3
Check Q512, D511, D508 and FBT.
Check Power parts.
Check protection case.
Check Q403 and Q404.
Does secondary voltage
appear at D608, D609, D610,
D611 and D612?
Does DC 12 V appear at Pin 2 of
IC603?
Check IC600
and IC603.
Check IC401.
Does H-out signal appear at Pin
26 of IC401?
7-4 No Raster (1)
Yes
No
Yes
No
Yes
No
Does DC +5 V, DC +12 V appear
at Pins 29, and 32 of IC401?
Yes
No
Does signal appear at base
of Q405?
Yes
No
Check Q405.
Does signal appear at collector
of Q405?
Yes
No
Check Q410.
Does flyback signal appear at
collector of Q410?
Yes
No
Check Q506, Q507, Q508 and Q509.
Does switching pulse appear at
base and collector of Q509?
Yes
No
Check IC501 and FBT.
Does signal appear at gate
of Q512?
Yes
No
WAVEFORMS
6
14
22
23
If in a protection case, you must check these case
• Check CN401 and CN402.
• Check Screen VR.
• Check VR501.
9.24 V (IC401, #26)
CH1 P-P = 9.24 V CH1 RMS = 6.048 V
6
1.072 kV (Q410, Collector)
CH1 P-P = 1.072 kV CH1 RMS = 310.0 V
14
6.80 V (Q509, Base)
CH1 P-P = 6.80 V CH1 RMS = 1.456 V
22
952 V (Q509, Collector)
CH1 P-P = 952 V CH1 RMS = 307.2 V
23
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