2-1
1. MAIN, FRONT & TUNER PART
No
Symptom
Check Point
Location No.
SYSTEM CONTROL
1
No Power
Checked the Fuse.
CN801
Checked the Back up Vdd, Gnd.
CN801(16,15)
Checked the Micom Back Up Vdd.
IC301(14), D307, IC401(30,47,50,99,100)
Checked the Micom Ground.
IC401(20,51,97,98)
Checked the Reset.
IC402, IC401(90)
Checked the X-tal.
X401, X402
Checked the ACC in. Q301, Q302, IC401(38),
C
N801(14)
Checked the detachable switch.
SW401, IC401(73)
Checked the flipdown Detector.
CN901(19), IC401(74)
Checked the Key line.
IC401(52,53)
2
Not available Remocon
Checked the Remocon Sens Vdd.
CN901(14), Q316, Q317, D307
Checked the Remocon Sens line.
RM
901, IC401(5)
3
Not available to Volume control
Checked the Encoder Volume.
SW901, IC401(40,41)
4
Not available to Key Control
Checked Tact switch.
SW902 ~ SW918
Checked Key line.
IC410(52,53)
5
No sound
Checked the E-VR Vdd.
IC301(10), IC601(16)
Checked the E-VR Ground.
IC601(1,22)
Checked the E-VR control.
IC601(22,23), IC401(1,2)
Checked the E-VR Signal in/out.
IC601(3,5,6,7,10,11)
IC601(12,13,14,15)
Checked the E-VR Mute Control
IC601(19), IC401(6)
* Power IC
Checked the Power IC Vdd.
IC801(6,20)
: Refer to next page
Checked the Power IC Ground.
IC801(1,2,8,13,18,24)
Checked the Power IC Control.
IC801(4, 22), IC401(3,10)
Checked the Power IC Signal in/out.
IC801(11,12,14,15)
IC801(3,5,7,9,17,19,21,23)
Checked the Power IC Mute.
IC801(22)
Checked the Power IC Standby.
IC801(4)
Checked the Power IC Ripple.
IC801(10)
Checked the Main Connector.
CN801(1,2,3,4,8,9,12,13)
6
No Line out signal
Checked the E-VR Vdd.
IC301(10), IC601(16)
Checked the E-VR Ground.
IC601(1,22)
Checked the E-VR control.
IC601(20,21), IC401(1,2)
Checked the E-VR Signal in/out.
IC601(3,5,6,7,10,11)
IC601(12,13,14,15)
Checked the Line out Mute circuit
Q705, IC401(48)
Check the Line out Jack
CN703
8
Heard Pop Noise
Checked the Mute Control.
IC601(19), IC801(4,22), IC401(3,6,10)
Checked the AF Mute.
TU101(19), IC401(4)
9
Not avaliable to Telephone Mute
Checked the telephone Mute Control.
CN801(5), Q305, Q306, IC401(62)
Checked the Mute Control.
IC601(19), IC801(4,22), IC401(3,6,10)
10 Not avaliable to ANT(Motor Type) Control Checked the ANT Control.
IC301(12,13), IC401(87)
11 Not avaliable to Remote
Checked the Remote control.
CN801(6), IC402(1,2,4), Q308, Q309
(External AMP)
IC401(63,64)
12 No output Beep sound.
Checked the Beep Control.
IC401(80)
ELECTRICAL TROUBLESHOOTING GUIDE & WAVEFORMS
SECTION 2 ELECTRICAL
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Only for training and service purposes
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