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LC-32RD2E/RU, LC-37RD2E/RU

4 – 1

LC32RD2E

Service Manual

 

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

NO

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

YES

Is F701 normal?

NO

Are both ends of C704 and C715 short-circuited when checking 
their resistance values?

YES

NO

YES

Replace F701.

Is a voltage of BU5V applied to pin (20, 21) of P701?
(Set the main power SW to OFF.)

C704 

• • • Check VA701, VA702 and D701.

C715 

• • • Check IC704 and IC705.

YES

                          

NO

Is a voltage of approx. 8 - 15V to pin (4) of IC705?

NO

Check IC705, IC708, D725 and Q724.

                          

YES

Check short circuit of 5V line (D737, C752, etc.). 

Is it a symptom that the relay clatters twice as soon as the main 
power SW is set to ON and the power is not supplied?

YES

                          

NO

Does the same symptom appear even if R858 (2.7k) 
is removed and the power is supplied again?

NO

Check IC704, D728, D762 and D736.
If there are no problems, check the resistance value between 
pins (1) and (5) of P704.

                          

YES

When the value is low (several 

Ω - several hundred Ω), discon-

nect P704.

Check Q724, D731, D734, IC707, D751, D753, 
D754, D741, D759 and D746.

If the value is still low, the parts of 24V line are defective.
When the resistance value is several k

Ω, check the inverter unit.

Does a relay noise sound? (Once)

NO

Are PCON1 and 2 [pins (1) and (2) of P702] at Hi (3V or more)?

YES

NO

YES

Check peripheral circuits of D738, R828 and D735.

Check peripheral circuits of Q712, Q713, 
Q721, Q723 and RY701.

There is a possibility that control by P-CON is not performed
properly. Check whether the “PFC_CON” and “PCON2” signals 
are sent from pins (47) and (49) of IC2301 (SUB_MYCON) of 
MAIN-UNIT.

LC-32RD2E/RU, LC-37RD2E/RU

4 – 2

                                             
No sound output in all modes.

                                             
Is the audio signal properly sent from pins (28) (L-ch) and (27) 
(R-ch) of IC3001?

NO

Check IC3001 or peripheral circuits.

YES

Is the audio signal of pins (3) (L-ch) and (5) (R-ch) of IC303 (OP-
AMP) sent properly?

NO

Check SC2704 and P1201 or peripheral circuits. Is the S-MUTE 
signal “L”?

YES

Is the audio signal of pin (4) of IC301 (R-ch)/IC302 (L-ch) 
(AUDIO-AMP) sent properly?

NO

Check HEAD-PHONE (J1301) or peripheral circuits.

YES

Is the audio signal output of pins (2, 1) (L-ch) and (4, 3) (R-ch) of 
P301 (AUDIO-CONNECTOR) normal?

NO

Check P301 (AUDIO-CONNECTOR) and peripheral circuits.

YES

Check Speaker Box (right and left) and wire harness.

                                            
No audio output during UHF/VHF reception

                                            
Checklist: 
1) Is the volume set to MIN or MUTE on the remote control? 

••• Set the desired volume.

2) Are headphones connected to HEADPHONE (J1301)? 

••• Disconnect them.

3) Is ANT-CABLE disconnected or connected improperly? 

••• Connect it correctly as per the operation manual.

                                            

NO

Refer to “No sound output in all modes”.

                                            

NO

Is the SIF signal (SIF_IN+) sent to pin (31) of IC3001 (VCT)?

YES

Check whether +5V and +8V are supplied to pins (33) and (18) of 
IC3001 respectively. Or, check peripheral circuits.

                                            

NO

Is the audio signal (SIF) sent from pin (1) of CONNECTOR 
(SC2742)?

YES

Check pin (31) of IC3001 (VCT) and peripheral circuits.

(TUNER)                              

NO

Is the audio signal (SIF) sent from pin (12) of IC201 (IF-
DEMOD)?

YES

Check Q203 (AMP) and peripheral circuits.

(TUNER)                              

NO

Is the SIF signal sent to pins (23) and (24) of IC201 (IF-
DEMOD)?

YES

Check IC201 and peripheral circuits.

(TUNER)                              

NO

Is the IF signal sent from pin (17) of TUNER (TU201)?

YES

Check FL202 and peripheral circuits.

NO

Check whether 5V (CONT) and 5V are supplied to pins (1) and 
(2) of TUNER (TU201) respectively. Check SDA/SCL and AGC 
signal.

YES

Replace TUNER (TU201).

LC-32RD2E/RU, LC-37RD2E/RU

4 – 3

                                             
No sound from an external input device connected to EXT1 
(SCART1).

<EXT1>                                
Is IN1-L audio signal sent from pin (6) of SCART1 terminal 
(J1101) to pin (14) of IC3001 (VCT)?

NO

Check pins (6) and (2) of SCART1 and connection to an external 
input device.

Is IN1-R audio signal sent from pin (2) of SCART1 terminal 
(J1101) to pin (13) of IC3001 (VCT)?

YES

Refer to “No sound output in all modes”.

                                             
No sound from an external input device connected to EXT2 
(SCART2).

<EXT2>                                
Is IN2-L audio signal sent from pin (27) of SCART2 terminal 
(J1101) to pin (12) of IC3001 (VCT)?

NO

Check pins (27) and (23) of SCART2 and connection to an exter-
nal input device.

Is IN2-R audio signal sent from pin (23) of SCART2 terminal 
(J1101) to pin (11) of IC3001 (VCT)?

YES

Refer to “No sound output in all modes”.

                                             
No sound from an external input device connected to EXT3.

<EXT3>                                
Is IN3-L audio signal sent from pin (3) of J1201 terminal to pin 
(16) of IC3001 (VCT)?

NO

Check pins (3) and (5) of EXT3 (J1201) and connection to an 
external input device.

Is IN3-R audio signal sent from pin (5) of J1201 terminal to pin 
(15) of IC3001 (VCT)?

YES

Refer to “No sound output in all modes”.

                                             
No sound from EXT4 (AUDIO) connecting an external input
device.

<EXT4>                                 
Is D-SUB-L audio signal sent from J2711 to pin (15) of IC2721 
(SW)?

NO

Check the line between J2711 and IC2721.
(Q2711, Q2712, etc.)

Is D-SUB-R audio signal sent from J2711 to pin (2) of IC2721 
(SW)?

YES

Is D-SUB-L audio signal sent to pin (10) of IC3001?
Is D-SUB-R audio signal sent to pin (9) of IC3001?

NO

Check the line between IC2721 and IC3001.

YES

Refer to “No sound output in all modes”.

LC-32RD2E/RU, LC-37RD2E/RU

4 – 4

                                             
No sound from EXT5 (AUDIO) connecting an external input
device.

                                             
Check that Option-HDMI Setup-Audio select is set to “Analog”.

<EXT5>                                

OK

Is HDMI-L audio signal sent from J2701 terminal to pin (14) of 
IC2721 (SW)?

NO

Check the line between J2701 and IC2721.
(Q2701, Q2702, etc.)

Is HDMI-R audio signal sent from J2701 terminal to pin (5) of 
IC2721 (SW)?

YES

Is HDMI-L audio signal sent to pins (10) of IC3001?
Is HDMI-R audio signal sent to pins (9) of IC3001?

NO

Check output of pins (13) and (3) of IC2721 and peripheral cir-
cuits.

YES

Refer to “No sound output in all modes”.

                                             
No sound from an external input device connected to EXT7.

<EXT7>                                
Is EX-L audio signal sent from pin (5) of J1201 terminal to pin 
(12) of IC2721 (SW)?

NO

Check the line between J1401 and IC2721.
(Q1401, Q1402, P1401/P2791, etc.)

Is EX-R audio signal sent from pin (4) of J1201 terminal to pin (1) 
of IC2721 (SW)?

YES

Is EX-L audio signal sent to pin (10) of IC3001 (VCT)?
Is EX-R audio signal sent to pin (9) of IC3001 (VCT)?

NO

Check the line between IC2721 and IC3001.

YES

Refer to “No sound output in all modes”.