
KDC-MP4028/MP428/MP6029
3
●ELECTRIC UNIT (X34-338x-xx)
Ref. No. Application / Function Operation / Condition / Compatibility
IC1 SYSTEM µ-COM Controls FM/AM tuner, the changer, CD mechanism, panel, volume and tone.
IC2 E-VOL Controls the source, volume, tone.
IC3 A8V REF POWER SUPPLY Outputs 1.27V.
IC4 POWER IC Amplifies the front L/R and the rear L/R.
IC5 ILL+B POWER SUPPLY Outputs 1.225V.
IC6 MUTE LOGIC Controls logic for muting.
IC7 RESET IC “L” when detection voltage goes below 3.6V.
IC11
4V PREOUT POWER SUPPLY
Outputs reference voltage for 4V preout.
IC12 SW REGULATOR Power supply for FL+B and CD mecha D5V.
IC902 SVR/3.3V SUPPLY Outputs SVR voltage and 3.3V.
Q1,2 B.U.5V AVR While BU is applied, BU5V AVR is output.
Q3,11 SW5V When Q11’s base goes “H”, SW5V is output.
Q4,9 SW14V When Q9’s base goes “H”, SW14V is output.
Q5,6 AUDIO 8V AVR When Q6’s 2nd pin goes “H”, A8V AVR outputs 8.0V.
Q7,8 SERVO+B AVR When Q8’s base goes “H”, AVR 7.5V is output.
Q12 IC12 SW When Q12’s base goes “L”, IC12 turns on.
Q13 PANEL 5V When Q13’s base goes “L”, PANEL 5V is output.
Q14 4V PRE+B If Q15’s emitter shorts GND, Q14’s emitter level goes GND, after that Q14’s B-E level goes
(SHORT PROTECTION) over 0.6V, Q14 turns on, and Q15 turns off.
Q15,16 4V PRE+B When Q15’s base goes “H”, 12V is output.
Q101,102 P-ANT SW When Q102’s base goes “H”, P-ANT SW 14V is output.
Q103,106 P-CON SW When Q106’s base goes “H”, AVR 14V is output.
Q104,105 P-CON PROTECTION When P-CON output voltage fallen is detected, protection functions.
Protects Q103 malfunction when P-CON SW turns on.
Q108 SMALL LAMP DET SW When Q108’s base goes “H”, Q108 turns on.
Q109,110 SERGE DET When Q109’s base goes “H”, IC4 state is changed into standby.
Q111 B.U.DET When Q111’s base goes “H”, Q111 turns on.
Q112 ACC DET When Q112’s base goes “H”, Q112 turns on.
Q113 MUTE DRIVER When the base goes “L”, preout mute driver turns on.
Q114 MUTE DRIVER When reset functions, Q114 turns on.
Q115,116 PREOUT MUTE DRIVER When the base goes “L”, preout mute driver turns on.
Q299 TUNER 8V SW When Q299’s 2nd pin goes “H”, tuner 8V is output.
Q300,301 AM+B When Q301’s base goes “H”, AM+B is output.
Q302,303 TUNER 8V When Q303’s base goes “H”, tuner 8V is output.
Q304 DSI DRIVER DSI lights when the base is “H”.DSI turns off when the base is “L”.
DSI turns on and off when panel is taken off.
Q305,306 SW ILL+B When Q306’s base goes “H”, SW ILL+B 11V is output.
Q400~405 PREOUT MUTE SW When the base goes “H”, preout is muted.
Q905~907 SVR+B SVR voltage is supplied from the outside.
COMPONENTS DESCRIPTION