LC-52XL1E (serv.man3). Adjustment Procedure - Sharp TV Service Manual (repair manual). Page 2

LC-46XL1E/RU, LC-52XL1E/RU

4 – 2

 No sound (1) (during the reception of TV broadcasting) 

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.

Is the audio signal (L/R) 
sent from pins (28) and 
(27) of IC3701 (MSP)? 

NO

Is the SIF signal 
(ANA_IN1+) sent to pin 
(67) of IC3701 (MSP)?

YES

Check whether +5V and 
+8V are supplied to pins 
(12) and (39) of IC3701 
respectively. Or, check 
peripheral circuits.

(AV-UNIT)

YES

NO

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

NO

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

Is the audio signal (SIF) 
sent from pin (1) of CON-
NECTOR (SC2705)?

YES

Check pin (67) of IC3701 
(MSP) and peripheral cir-
cuits.

YES

(TUNER)

NO

Is the audio signal of pin 
(4) of IC301/IC302 
(AUDIO-AMP) sent prop-
erly?

NO

Check HEAD-PHONE 
(J1301) or peripheral 
circuits. 

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

YES

Check CONNECTOR 
(P201) and peripheral cir-
cuits.

YES

NO

Is the audio signal output 
of pins (2) and (4) of P301 
(AUDIO-CONNECTOR) 
normal? 

NO

Check P301 (AUDIO- 
CONNECTOR) and 
peripheral circuits. 

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

YES

Confirm whether +5V is 
supplied to IC201. 
Or, please check the 
peripheral circuit.

YES

NO

Check SP-BOX (right and 
left) and wire harness. 

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

YES

Check soldering the termi-
nal and peripheral circuits.

NO

Check whether 5V 
(CONT) and 5V are sup-
plied to pins (1) and (2) of 
TUNER (TU201) respec-
tively.
Check SDA/SCL and AGC 
signal.

YES

Replace TUNER (TU201).