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LC-32LE40E-LC-42LE40E 

41 

CHAPTER 4. 

 

[1] TROUBLESHOOTING TABLE 
 

↓ 

 
 

LINE_FILTER_UNIT:     

     

↓ YES

 

 
 
 
 
 

 

POWER_UNIT                  

↓YES

  

 
 
 

↓YES 

 
 
 
 

↓YES 

 
 
 
 
 
 
 

The sound is not emitted from the speaker though the picture has come out. 

↓ 

No sound output in all modes?

 

TERMINAL UNIT:

    

     ↓ 

 

 

↓YES 

 
 

↓YES 

 
 

↓YES 

 
 

↓YES 

 
 
 

Are the power cord and harness in the unit properly connected? 

NO 

Connect the power cord and harness properly, and turn on the 
power.

Is F9901/F9902 normal? 

NO 

 

LINE_FILTER_UNIT: 
Isn't NR9901,NR9902,IC9901,L9901,L9902(32”)/L9903(42”),etc. 
out of order? Moreover, whether the short-circuit with the 
circumference circuit is checked. 
POWER_UNIT: 
BD9901, FB9901, (FB9902, FB9906, D9101)(32”)/(FB902, 
FB9801, D9801)(42”) etc. out of order? Moreover, whether the 
short-circuit with the circumference circuit is checked. 

Is B+_main(32”)/B1+(42”) output? (Set the main power SW to ON.)

Does the PFC circuit operate normally? 
The circuit around the protection circuit etc. is checked.

 

NO 

 

Is a voltage of +5.2V applied to pin (2,3) of connector 
(CN9304(32”)/CN907(42”))? 
(Set the main power SW to ON.) 

Does the switching circuit operate normally? 
Check circuit around the primary side (IC9301, T9301, 
D9303(32”)/D9307(42”),etc.), the secondary side ((D9302, 
L9301, ZD9316)(32”)/(D9308, L9304, ZD9103(42”), etc.), and 
the protection circuit.

NO 

 

Are 12 and 24V output as for the power on/off switch when it is on?

NO 

 

Does the inverter circuit operate normally? 
Check circuit around the primary side (IC9103, T9101, Q9101, 
etc.)(32”)/(IC9101, T9101, Q9101, Q9102)(42”), the secondary 
side ((IC9101, D9102, D9103)(32”)/(IC9302, D9115, 
D9116)(42”), etc.), and the protection circuit.

Is the audio signal output of IC U401 normal? 

NO 

 

Check IC U401 and its peripheral circuits.

Is audio signal input to pin (15/20/21/22) of IC U602 (AMP)?

 

NO 

 

Check the line between IC U401 and IC U602.

Is MUTE circuit [AMP_MUTE_LINE, POWERUP_LINE] normal?

Is the audio signal output of pin (1,2) (R) and pin (3,4) (L) of 
CN601(AOUDIO-CONNECTOR) normal? 

NO 

 

Check the AMP_MUTE_LINE and POWERUP_LINE. (Q652, 
Q653 etc.) 

NO 

 

Check IC U602 and its peripheral circuits.

Check Speaker (right and left) and wire harness.

 

LC-32LE40E-LC-42LE40E 

42 

 

No sound (during the reception of TV broadcasting) 

↓ 

Does not the sound go out though the picture has come out when TV is received?

 

MAIN UNIT:

  

 

     ↓ 

 

 

↓YES 
 
 
↓YES 

 
 
 

No sound from external input devices (1) 

↓ 

Does not the sound of the audio signal input to SCART go out? 

TEREMINAL UNIT:

   

    ↓ 

 

 

↓YES 
 
 
↓YES 
 
 
↓YES 

 
 
 
 

No sound from external input devices (2) 

↓ 

Does not the sound of the audio signal input  to Component go out? 

MAIN UNIT:

  

 

    ↓ 

 

 

↓YES 
 
 
 
↓YES 
 
 
↓YES 

 
 

Is the DIF signal output from pin (13/14) of Tuner (TU101)?

 

NO 

 

Check the tuner and its peripheral circuits. Replace as required.

Refer to “No sound output in all modes”.

 

Is the audio signal properly sent to pin (2)(YPbPr_L_In) and pin 
(4)(YPbPr_R_In) of CN116?

 

NO 

Check the connection to CN116 and the external input device.

Refer to “No sound output in all modes”.

 

Is the audio signal properly sent to pin5 (YPbPr_LIn) and pin14 
(YPbPr_RIn) of IC U605?

 

NO 

 

Check the line between CN116 and IC U605.

Is the DIF signal sent to pin (184/185) of IC U401?

 

NO 

 

Check IC U401 its peripheral circuits.

 

Is the audio signal properly sent to pin 6 (SCT1_AUL_IN) and pin2 
 (SCT1_AUR_IN) of SCART (CN151)?

 

NO 

Check the setting of an external input device that connects of 
CN151.

 

Refer to “No sound output in all modes”.

 

Is the audio signal properly sent to pin (2&15) of IC U605?

 

NO 

 

Check the line between CN151 and IC U605.

 

Is the audio signal properly sent to pin IC U401?

 

NO 

 

Check the line between U605 and IC U401.

 

Is the audio signal properly sent to IC U401?

 

NO 

 

Check the line between U605 and IC U401.

 

LC-32LE40E-LC-42LE40E 

43 

 

 

↓ 

Does not the sound of the audio signal input to (Composite, Y/C) go out?

 

MAIN UNIT:

  

 

     ↓ 

 

 

↓YES 
 
 
↓YES 
 
 
↓YES 

 
 
 

No sound from external input devices (4) 

↓ 

Does not the sound of the audio signal input to (VGA) go out?

 

MAIN UNIT:

  

 

     ↓ 

 

 

↓YES 
 
 
↓YES 
 
 
↓YES 

 
 
 

No sound from external input devices (5) 

↓ 

Does not the sound of the audio signal input to (HDMI1/2) go out?

 

↓ 

 

 

↓YES 

 
 

Is the audio signal properly sent to pin (4) (AV1_AudioLIN) and pin 
(6) (AV1_AudioRIN) of CN136?

 

NO 

 

Check the connection to CN136 and the external input device.

Refer to “No sound output in all modes”.

 

Is the audio signal properly sent to pin4 (AV1_LIn) and pin11 
(AV1_RIn) of IC U605?

 

NO 

 

Check the line between CN136 and IC U605.

Is the audio signal properly sent to pin (2) (VGA_L_In) and pin (3) 
(VGA_R_In) of CN102?

 

NO 

 

Check the connection to CN102 and the external input device.

Refer to “No sound output in all modes”.

 

Is the audio signal properly sent to pin1 (VGA_LIn) and pin12 
(VGA RIn) of IC U605?

 

NO 

 

Check the line between CN102 and IC U605.

Refer to “No sound output in all modes”.

 

Is picture of the signal input from HDMI 1/2 displayed?

 

NO 

 

Refer to “Does not the picture of the HDMI signal input to 
HDMI1/2 go out?”.

 

Is the audio signal properly sent to IC U401?

 

NO 

 

Check the line between U605 and IC U401.

 

Is the audio signal properly sent to IC U401?

 

NO 

 

Check the line between U605 and IC U401.

 

LC-32LE40E-LC-42LE40E 

44 

 

↓ 

The audio signal of UHF/VHF is not output from SCART. 

 TEREMINAL UNIT:

  

    ↓ 

 

 

↓NO 
 
 
↓NO 

 
 
 

↓ 

The audio signal of UHF/VHF is not output from audio line output terminal. 

 TEREMINAL UNIT:

  

    ↓ 

 

 

↓NO 
 
 
↓NO 

 
 
 

↓ 

No audio signal output from SPDIF_OUTPUT terminal. 

 TEREMINAL UNIT:

  

    ↓ 

 

 

↓NO 

 
 
 

↓ 

No sound from HEADPHONE_OUTPUT terminal. 

 TEREMINAL UNIT:

  

    ↓ 

 

 

↓YES 
 
 
↓YES 
 
 
↓YES 

 
 

Is audio signal output from IC U603 sent to pin (3) 
(SCT1_AUL_OUT) and pin(1)(SCT1_AUR_OUT) of 
SCART(CN151)? 

YES 

 

Check the connection to SCART1 and external devices.

Check IC U401 and its peripheral circuits. 

Is audio signal output from IC U401 is sent to pin (2) (1IN-) and pin 
(6) (2IN-)of IC U603?

YES 

 

Check the line between IC U401 and IC U603. 

Is audio signal output from IC U601 sent to pin 
(4)(SCT2_AUL_OUT) and pin(6)(SCT2_AUR_OUT) of 
SCART2(CN152)? 

YES 

 

Check the connection to AV output and external devices. 

Check IC U401 and its peripheral circuits. 

Is audio signal output from IC U401 is sent to IC U601? 

YES 

 

Check the line between IC U401 and IC U601. 

Is ASPDIF audio signal output from pin (206) of IC U401 to pin (2) 
of connector CN117? 

YES 

 

Check the connection to SPDIF_OUT and external devices. 

Check IC U401 and its peripheral circuits. 

Is the HP_DET# signal input into pin (253) of IC U401 from pin (6) 
of a headphone terminal (CN602)? 

NO 

 

Check the connection to CN602 and external headphone is plug
in well. 

Check IC U401 and its peripheral circuits. 

Is the audio signal output from IC U602 to pin (2) (HPOUTL) and 
pin (3) (HPOUTR) of headphone terminal CN602?

NO 

 

Check the line between IC U602 and CN602.

 

Is the audio signal output from IC U401 pin (201) and pin (203) 
sent to pin (1)(HPL IN) and pin(4)(HPR IN) of IC U602?

NO 

 

Check the line between IC U401 and IC U602.