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CONFIDENTIAL
5 Troubleshooting
5-1 Parts Level Troubleshooting
Notes: Check the following circuits. · No raster appears: Power circuit, Horizontal output circuit. · High voltage develops but no raster appears: Video output circuits. · High voltage does not develop: Horizontal output circuits.
5-1-1 No Power Supply
Check and replace D601 and FH1
WAVEFORMS
1 100 V (IC601, #1)
Chirping noise exists?
Yes
Check and replace IC601.
No Repeating start? Yes Check and replace D606.
CH1 P-P = 100 V CH1 RMS = 350.2 V
No
1
IC601 Pin 1 waveform is right?
No
Check and replace D614, IC601, Q602, and ZD601.
Yes C622 Voltage is 13 V ± 0.5V? No Check and replace IC201, IC301, IC401, Q402, and Q404.
Yes Operate normally? Yes Verify voltages. No Replace Main board.
Done.
CA17K*/CA17J*
5-1
5 Troubleshooting
CONFIDENTIAL
WAVEFORMS
2 100 V (IC601, #1)
5-1-2 DPMS Failure
Check signal source H/V Sync. video level.
Make No H/V Sync. (power off mode)
LED blinks?
No
Check IC201 Pin 40.
CH1 P-P = 100 V
CH1 RMS = 325.8 V
Yes +12 V line off? No Check IC201 Pin 6.
Yes
2
IC601 Pin 1 output voltage exists? Yes Done.
No
Refer to 5-1-1 No Power Supply.
5-2
CA17K*/CA17J*
5 Troubleshooting
CONFIDENTIAL
No Does DC 12V appear at Pin 10 of IC401? Yes No Check 12 V line.
5-1-3 H_Deflection Failure
Does PWM output signal appear at Pin 6 (B_out) of IC401? Yes
3
WAVEFORMS
Check IC401. 3 2.00 V (IC401, #6) Does Horizontal pluse signal appear at Pin 8 of IC401? Yes
5
4
No
Check IC401.
Does 110 Vp-p signal appear at Collector of Q403? Yes Check Q402, Q404 and T401.
No
Check Q403.
CH1 P-P = 2.00V CH1 RMS = 5.868V
4 2.00V (IC401, #8)
CH1 P-P = 2.00V CH1 RMS = 5.868V
5 20.0 V (Q403, Collector)
5-1-4 S Correction Failure
Check S1 ~ S4 signal.
S1~S4 signals are right at each frequency block? Yes Check and replace Q404, Q409, Q410, Q411, Q414, Q415, Q416, Q420, and Q421.
No
Check and replace IC201.
CH1 P-P = 20.0 V CH1 RMS = 46.80V
CA17K*/CA17J*
5-3
5 Troubleshooting
CONFIDENTIAL
No Replace IC201.
5-1-5 H_Lin. Failure
IC201 Pin 21 voltage varies with different H_Lin. DAC values? Yes IC603 Pin 9 voltage varies with different H_Lin. DAC values? Yes Check Q412, Q413 and T402. No Check +13V, Coil_5V line. Check some parts around IC603.
5-1-6 Invariable H_Size
IC401 Pin 6 voltage varies with different B_Out DAC values? Yes Q402 Gate output duty varies with different B_Out DAC values? No Check some parts around Q402, IC401 Pin 3 ~ 6. No
Check and replace IC401.
5-1-7 Abnormal H_Size
IC401 Pin 11 output duty varies with different B+ offset DAC values? Yes
6
No
WAVEFORMS
Check and replace IC201. 6 200 V (Q404, Collector)
Q404 Collector waveform is right? Yes Check some parts around D409 and L401.
No
Check and replace Q405, Q406, Q407, and Q408.
CH1 P-P = 200V CH1 RMS = 387.2V
5-4
CA17K*/CA17J*
5 Troubleshooting
CONFIDENTIAL
No
5-1-8 Side Pin or Trap Failure WAVEFORMS
Check and replace IC401. 7 1.00 V (IC401, #11) Yes Refer to 5-1-7 Abnormal H_Size.
7
IC401 Pin 11 output exists?
CH1 P-P = 1.00V CH1 RMS = 3.008 V
5-1-9 Para. or Pin Balance Failure
IC401 Pin 11 output varies with different DAC values? No Replace IC401. Yes
Refer to 5-1-7 Abnormal H_Size.
5-1-10 Tilt Failure
Check tilt connector connection
IC201 Pin 20 output duty varies with different DAC values? Yes IC603 Pin 13 output varies with different DAC values? Yes Check and replace Q301 and Q302.
No
Check and replace IC201.
No
Check and replace IC603.
CA17K*/CA17J*
5-5
5 Troubleshooting
CONFIDENTIAL
WAVEFORMS
No Refer to 5-1-1 No Power Supply. 8 500 V (IC401, #12)
5-1-11 V Deflection Failure
13V and 10V lines are on?
Yes
8
IC401 Pin 12 output exists?
No
Check and replace IC401.
Yes
9
CH1 P-P = 500 V CH1 RMS = 1.425 V
IC301 Pin 6 output exists?
No
Check and replace some parts around IC301.
9
10.0 V (IC301, #6)
Yes Check DY connector connection.
CH1 P-P = 10.0 V CH1 RMS = 5.06 V
5-1-12 V Size or Position Variation Failure
IC401 Pin 12 output varies with different DAC values? Yes Check and replace IC301. No
Check and replace IC201 and IC401.
5-6
CA17K*/CA17J*
5 Troubleshooting
CONFIDENTIAL
WAVEFORMS
No Check and replace IC401 and +12 V line. 3 2.00 V (IC401, #6)
5-1-13 High Voltage Failure
3
IC401 Pin 6 OSC pulse exists?
Yes
10
Q402 Gate driving pulse exists?
No
Check and replace Q401 and Q423.
Yes
11
CH1 P-P = 2.00 V CH1 RMS = 5.868 V
Q402 Drain pulse exists?
No
Check and replace D401, Q403 and L402.
10 2.00 V (Q402, Gate)
Yes Done.
CH1 P-P = 2.00 V CH1 RMS = 7.692V
5-1-14 ABL Failure
11 50.0 V (Q402, Drain)
Input full white pattern to monitor.
IC101 Pin 8 input exists and varies with different patterns? Yes Check CN102.
No
Check and replace IC101.
CH1 P-P = 50.0 V CH1 RMS = 73.7V
T501 Pin 8 output exists?
No
Check and replace T501.
Yes IC201 Pin 26 output exists and varies with different patterns? Yes Done. No Check and replace IC201.
CA17K*/CA17J*
5-7
5 Troubleshooting
CONFIDENTIAL
No
5-1-15 Dynamic Focus Failure WAVEFORMS
Replace the IC401. 12 2.00 V (IC401, #32) IC401 Pin 32 output is right?
12
Yes Some parts around Q551 are right? No Replace failed part.
Yes
13
CH1 P-P = 2.00V CH1 RMS = 6.124V
T502 Pin 6 input is right?
No
Check and replace C432.
13 50.0 V (T502, #6)
Yes
14
T502 Pin 1 output is right?
No
Replace the T502.
CH1 P-P = 50.0V CH1 RMS = 75.6V
Yes Check the connection between FBT Focus pin and CRT Socket PCB.
14 100 V (T502, #1)
CH1 P-P = 100V CH1 RMS = 124.0V
5-8
CA17K*/CA17J*
5 Troubleshooting
CONFIDENTIAL
WAVEFORMS
15 1.00 V (IC102,#5, 8, 10)
5-1-16 No Video
Check signal cable and connection.
15
IC102 Pin 5, 8 and 10 inputs are right? Yes
No
Check the signal cable connection.
16
IC102 Pin 25, 28 and 30 outputs are right? Yes
No
Check I2C bus and +12 V line. 16 1.00 V (IC102, #25,28,30)
17
IC105 Pin 1, 3 and 5 outputs are right? Yes Cathode DC levels are right?
No
Check +12 V, +80 V line. Check and replace IC105.
No
Check +80 V line. Check and replace IC104 Check IC102 Pin 19, 20, 21.
17 20.0 V (IC105, #1, 3, 5)
Yes G2 voltage is right? No Check G2 wire, CRT Socket board and FBT.
Yes Change CRT. Yes Done.
CA17K*/CA17J*
5-9
5 Troubleshooting
CONFIDENTIAL
WAVEFORMS
18 1.00 V (IC101, #20, 22, 24)
5-1-17 No Highlight Zone (CA17J* Only)
IC101 Pin 2, 4 and 6 inputs are right? Yes
18
IC101 Pin 20, 22 and 24 outputs are right? Yes IC101 Pin 12, 13 are right? 2 (I C Data / Clock Line)
No
Check +5V IC101 pin 1, 23.
19 1.00 V (IC101, #14) No Check Micom (IC201) 2 I C Data / Clock Line.
19 20
IC101 Pin 14, 15 and V_FLB, CLAMP waveforms are right?
No
Check CLAMP, V_FLB waveforms. 20 1.00 V (IC101, #15)
Done.
5-1-18 Micom Failure
No
IC201 Pin 11 input voltage is 5V?
Check IC604.
Yes
21
IC201 Pin 13 and 14 inputs are right? Yes IC201 Pin 18 input is right?
No
Check C202, C203 and X201.
WAVEFORMS
21 1.00 V (IC201, #13, 14)
No
Check IC605 and 5V.
Yes All in/output values are right? No
CH1 P-P = 1.00 V CH1 RMS = 2.108V
Replace IC201.
Yes Done.
5-10
CA17K*/CA17J*
5 Troubleshooting
CONFIDENTIAL
No
5-1-19 OSD Failure WAVEFORMS
Check +5V Line. 22 1.00 V (IC103, #5, 24) Yes Check IC103 Pin 7, 8 I C Data / Clock Line? Yes
CH1 P-P = 1.00V CH1 RMS = 4.516V
2
22
IC103 Pin 5, 24 input is 5V?
No
Check I C wavefroms.
2
IC103 Pin 6 and 17 inputs are right? Yes
23
No
Check H-FLB 2, V_BLK.
23 1.00 V (IC103, #20, 21, 22)
IC103 Pin 20, 21 and 22 outputs are right? Yes Check and replace IC103.
No
Check and replace IC101.
Done.
CA17K*/CA17J*
5-11
5 Troubleshooting
CONFIDENTIAL
No Check the button. (SW201 ~ SW204)
5-1-20 User Control Failure
Does the DC level change at Pin 36 of IC201 when you push the button S/W? Yes Check IC201, CN2 and CN206.
5-1-21 Degaussing Failure
Check degaussing connector.
RL601 operation is right?
Yes
Check D-coil and TH601.
No Q601 base input is right? Yes Check 13V Line. Check and replace Q601.
No IC201 Pin 4 output is right? No Check and replace IC201.
Yes Done.
5-12
CA17K*/CA17J*
5 Troubleshooting
CONFIDENTIAL
5-2 General Troubleshooting
5-2-1 No Picture
Yes
LED blinks?
Refer to 5-2-2 Shut down.
No LED is green color? Yes Check Micom.
No Check G2 voltage, high voltage and R, G, B cathode voltage.
5-2-2 Shut Down
Blinking LED's?
No
Check power supply.
Yes Scan failure? Yes Check horizontal, vertical deflection system and check power supply secondary voltages.
No Video failure? Yes Check Video board.
No Check and replace IC201.
Done.
CA17K*/CA17J*
5-13
5 Troubleshooting
CONFIDENTIAL
WAVEFORMS
No 24 10.0 V (R,G,B, Video)
5-2-3 Missing Color
Proper Video levels are on CN101 (D-Sub) Pin 1, 3 and 5? Yes
24
Check signal generator.
Proper Video signal is on all cathodes? Yes Proper DC voltage is on all cathodes? Yes G2 voltage is right? Yes Heater voltage is right?
No
Refer to 5-1-16 No Video.
CH1 P-P = 10.0V CH1 RMS = 17.02V
No
Check IC101 Pin 18, 21 and 24. Check QR01, QR02, QG01, QG02, QB01, and QB02.
No
Check D502, D518, Q501, D520, D521, and CN501.
No
Check D608, Q604 and T601.
Yes Is G2 voltage right? Yes Replace CRT. Yes Done. No Check D504, Q502 and T501.
5-14
CA17K*/CA17J*
5 Troubleshooting
CONFIDENTIAL
WAVEFORMS
25 5.00V (Q501, Emitter)
5-2-4 Visible Retrace
Check white balance adjustment.
G2 voltage is right?
No
Check D502, D518, Q501, Adjust G2.
Yes Blank pulse is on Pin 17 of IC401? No Check IC401.
CH1 P-P = 5.00V
CH1 RMS = 28.33V
Yes
25
26 20.00V (CRT Socket, G1) No Check Blank pulse is on Pin 17 of IC401 and Q303.
V_FLB pulse is on Collector of Q501? Yes
26
Does approve the Vertical pulse on the CRT Socket G1? Yes Done.
No
Check CN102 and CN201.
CH1 P-P = 20.0V CH1 RMS = 66.68V
CA17K*/CA17J*
5-15
5 Troubleshooting
CONFIDENTIAL
5-2-5 Unsynchronized Image
Check input signals Pin 2 and 3 of CN202.
Signals are right?
No
Check Video Cable.
Yes Signals at Pin 28 and 29 of IC201 are right? Yes Signals at Pin 14 and 15 of IC401 are right? Yes Check circuits on Main board. No Check IC401. No Check IC201.
Done.
5-16
CA17K*/CA17J*
5 Troubleshooting
CONFIDENTIAL
5-2-6 Misconvergence
Try readjusting convergence.
The convergence is now within spec.? No Readjust convergence.
Yes
Done.
The convergence is now within spec.? No Change CRT and readjust convergence.
Yes
Done.
Done.
CA17K*/CA17J*
5-17
5 Troubleshooting
CONFIDENTIAL
5-2-7 Poor Focus
Adjust focus VR of FBT.
Improved focus?
Yes
Aging monitor and check for focus change.
No Check focus leads from FBT to CRT Socket.
Check the CRT Socket.
Dynamic focus circuit is right?
No
Refer to 5-1-15 Dynamic Focus Failure.
Yes Replace the CRT and verify focus.
5-2-8 Purity Failure
Degaussing
Purity is right?
Yes
Done
No Degaussing circuit is right? No Refer to 5-1-20 Degaussing Failure.
Yes Replace CRT and verify purity.
5-18
CA17K*/CA17J*