Tecnico Electronica

CTC203
TROUBLESHOOTING

Main Troubleshooting Flow Chart
Dead Set

7-2

EEPROM Error Codes

7-3

System Control

7-4

Power Supply

7-5

Horizontal

7-6

Vertical

7-7

Tuner

7-8

Tuner Band Switching

7-9

Color

7-10

Video

7-11

Buttons

7-12

Infrared

7-12

OSD

7-13

Gemstar

7-14

F2PIP

7-15

Analog Comb

7-16

GeneralAudio Problems

7-18

Distorted Audio

7-20

Stereo Seperation

7-20

No Stereo

7-21

Sound Logic

7-22

Page 7-1

Return To Main Flow Chart

CTC203
TROUBLESHOOTING

DEAD SET TROUBLESHOOTING
Set Will Not Turn On

Degauss Relay
Switching
YES
ON/OFF?

Check EEPROM Error Codes
Using Chipper Check

NO

Microprocessor
U13101 Reset YES
Pin 51 = 5V?

CheckSystem Control

NO

Check Power Supplies

Page 7-2

Return To Main Flow Chart

CTC203
TROUBLESHOOTING

EEPROM Error Codes

Error code:
HEX

Chassis:

DEC

0
1
3
8
9
10
11
16

ALL
ALL
ALL
ALL
ALL
w/ F2PIP
ALL
ALL

12

18

ALL

DEC
34
44
102
128
160
186
196
198

Action

POWER CONTROL ERRORS

00
01
03
08
09
0A
0B
10
HEX
22
2C
66
80A0
BA
C4
C6

Error:

No Errors
16V_STBY fault
12V_RUN fault
T4chip XRP (X-ray protection)
T4chip POR (power on reset)
F2PIP POR
Stereo Decoder POR
Run I2C bus latched
Standby I2C bus latched

Check Power Supplies
Check Power Supplies
Check Power Supplies
Check Horizontal
Check F2PIP
Check General Audio
Check System Control
Check System Control

I2C ACKNOWLEDGE ERRORSw/Gemstar
w/ F2PIP
w/Gemstar
ALL
EEPROM
ALL
ALL
ALL

Failure to get acknowledge from Gemstar module
F2PIP fault
Gemstar bus fault
Stereo Decoder fault
EEPROM bus fault
T4chip fault
Main Tuner PLL bus fault
Main Tuner DAC bus fault

Page 7-3

Check Gemstar
Check F2PIP
Check Gemstar
Check General Audio
Check System Control
Check System Control
Check Tuner
Check TunerReturn To Main Flow Chart

CTC203
TROUBLESHOOTING

System Control Troubleshooting
Microprocessor
U13101
Pin 51 = 5V?

NO

YES

EEPROM
U13102
Pin 8 = 5V?

NO

Check Micro Reset Circuit.
Q13501, Q13503, etc.

U13101
Pin 20 ~4.5V? NO
YES

YES

Check R13128,
R13181,Q13104.
U13101 Pin 20
should be High
Impedance. If
not replace.

Replace Q13104
Microprocessor
U13101NO
Pins 40,42 = 4MHz?

Replace 4MHz Crystal Y13101,
R13107,C13106,C13107

YES

Plug in AC. Check Bus
Activity on U13101 Pins
23,24. Do Transmissions NO
Stop after a few moments?

Check EEPROM and Power
Supplies

YES

Microprocessor
U13101 KD1
Pin 5 = 5V Pulse?

NO

Check Power Supply

YES

Note: Pin 5, Drive
Line, should have a
20ms pulse. If this
pulse is seen on asense line then a
button is closed.

Microprocessor
U13101 Sense Lines
Pins 6,7,8 = Steady NO
5V with No pulses?

Check Front Panel for Stuck or
Shorted Button or Missing 5V.

YES

Check EEPROM Error Codes
Using Chipper Check

Page 7-4

Return To Main Flow Chart

CTC203
TROUBLESHOOTING

Power Supply Troubleshooting

Raw B+
@TP14210
~ 150V ?

NO

Check F14201,R14202,
CR14201-CR14204

YES

+16V stanby
Cathode CR14108
~ 16V?

NO

Check CR14108

YES

RegB+ Cathode
CR14106
~ 130V?

NO

Check RegB+ Circuit. R14116,U14101,U14102,
Q14102,Q14103,Q14106,Q14107,Q14101

YES

+5V stanby
U14103 Pin 3
~ 5.2V?

U14103 Pin 1
~ 14.8V? NO

NO

Check CR14110

YES

YES

Replace Q14104,Q14105
Replace U14103

If the Degaus
Relay isclicking
then the +12Vs
and +7.5Vs will
be ON only
momentarily at
turn ON.

+12V Switch
U14104 Pin 3
~ 12.2V?

U14104 Pin 1
~ 16V? NO

NO

YES

YES

Replace U14104

+7.5V Switch
U14150 Pin 3
~ 7.3V?

U14150 Pin 1
~ 10V? NO

NO

NO

Troubleshoot System
Control
Check R14151

YES

YES

Power Supplies OK

YES

U13101 Pin 19~5V
with Power Button
Pressed?...