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CDX-848X SERVICE MANUAL US Model AEP Model Ver 1.2 2001.06 UK Model Model Name Using Similar Mechanism NEW CD Drive Mechanism Type MG-251B-137 Optical Pick-up Name KSS-720A SPECIFICATIONS System Compact disc digital audio system Laser diode properties Material: GaAlAs Wavelength: 780 nm...
AND IN THE PARTS LIST ARE CRITICAL TO SAFE put a new CAUTION LABEL (3-223-913-11) to the chassis (U.S) OPERATION. REPLACE THESE COMPONENTS WITH sub assy. SONY PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB- LISHED BY SONY.
CDX-848X Ver 1.1 2001.05 NOTE FOR REPLACING IC201 TABLE OF CONTENTS IC201 on MAIN board for this set has been changed in the mid- way of manufacturing. SERVICING NOTES ............2 In a set that the former type of IC201 is mounted, SUB board is connected to MAIN board (conductor side).
When using the Sony CD adapter, make sure the three catches on the adapter are firmly latched onto the 8 cm CD. • Do not insert the Sony CD adapter CSA-8 in the magazine without a disc, malfunction may result. Slide open Remarques •...
CDX-848X Installation Installation Precautions Précautions • Choose the mounting location carefully, observing the following: • Choisir l’emplacement de montage en tenant compte des observations suivantes: — The unit is not subject to temperatures exceeding 55°C (131°F) (such as in a car parked in direct —...
— Protéger les pièces du coupleur des égratignures eet de la saleté. — If this unit is not connected to a car audio compatible with the Sony BUS optical digital transmission system, — Si cet appareil n’est pas raccordé à un autoradio compatible avec le système de transmission numérique optique reinstall the protective cap to its original position.
CDX-848X SECTION 2 DISASSEMBLY • This set can be disassembled in the order shown below. 2-1. DISASSEMBLY FLOW Note 1: The process described in can be performed in any order. Note 2: Without completing the process described in , the next process can not be performed.
CDX-848X 2-4. JACK BOARD, DIGITAL OUT BOARD 2 connector (CN902) 5 connector (CN701) Remove the jack board in the direction of the arrow. 1 ground point screw (PTT2.6 × 6) 3 jack board 6 digital out board 4 screw (BVTT2 × 6) 2-5.
CDX-848X 2-6. ELJ MOTOR ASSY (ELEVATOR) (M104) 1 screw (PTT2 × 4) 2 bracket (EVM.S) 4 ELJ motor assy (elevator) (M104) 3 spacer (MO) 2-7. ESCUTCHEON (T) 3 two claws 2 Remove the claw in the direction of arrow A .
CDX-848X 2-8. CHASSIS (U.S) SUB ASSY 2 Remove the edge in the direction 1 three screws of arrow A . (PTT2 × 4) 1 two screws (PTT2 × 4) 5 chassis (U.S) sub assy 1 screw (PTT2 × 4) 4 spring (SUT) 2-9.
CDX-848X 2-10. RF BOARD 3 two screws (PTT2 × 4) 4 RF board 3 two screws (PS2 × 4) 2 Remove four solders of the LSW board leads and spindle motor leads (M102). 2 Remove two solders of the sled motor leads 1 OP flexible board (CN102).
CDX-848X 2-12. LSW BOARD, SPINDLE MOTOR (S) SUB ASSY (M102) 8 two precision screws (P1.7 × 2.2) 3 spring (chucking) 6 retainer (disc) 1 precision screw (P2 × 2.5) 4 precision screw (P2 × 2.2) 5 bracket (CP) 2 LSW board 9 Remove the spindle motor (S) sub assy (M102) in the direction of the arrow.
CDX-848X 3-3. GEAR (LOMINI)/(LOAD CAM) ASSY gear (LOAD 2) 2 Attach the gear (LOMINI) at the position shown in Fig. A. gear (LOMINI) shaft (rotary prevention C) chuck plate 1 Move the lever (LOCK 3A) fully in the direction of arrow B to move the chuck plate up.
CDX-848X SECTION 4 MECHANICAL ADJUSTMENT • Elevator Height (Address) Adjustment Adjustment Method: Note: This adjustments is necessary when the system controller (IC201), variable resistor (RV201), slider (R), slider (L), or chassis (ELV) 1. Connect this set to the master unit (e.g. MDX-C7970/C7970R), was replaced for any repair.
CDX-848X SECTION 5 ELECTRICAL CHECK Note: Focus Bias Check 1. This check is performed with the set placed horizontally. 2. Power supply voltage: DC14.4 V (more than 3 A). Connection: 3. Be sure to use the disc “YEDS-18” parts code: 3-702-101-01, but only –...
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CDX-848X Tracking Offset Check Connection: – RF Board (Component Side) – oscilloscope (DC range) TP (VC) – IC101 TP (TE) Procedure: 1. Connect the oscilloscope to TP (TE) and TP (VC) on the RF board. 2. Put the set into play mode by loading the disc (YEDS-18).
RESET SIGNAL CN901 (2/2) RESET GENERATOR IC303 CONTROL PS901 +3.3V B. UP +3.3V REGULATOR B. UP Q303, 304 BUS INTERFACE (FOR SONY BUS) IC302 DATA DATA UNI SI UNI SO UNI CK BUSON OUT BUSON BUSON BUSON OUT BUSON IN RESET...
CDX-848X 6-3. NOTE FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS • Circuit Boards Location Note on Printed Wiring Board: Note on Schematic Diagram: • All capacitors are in µF unless otherwise noted. pF: µµF • X : parts extracted from the component side.
CDX-848X 6-5. SCHEMATIC DIAGRAM – RF/LSW Boards – • See page 30 for for Waveforms. • See page 30 for IC Block Diagrams. (Page 26) The components identified by mark 0 or dotted line with mark 0 are critical for safety.
CDX-848X Ver 1.1 2001.05 6-9. SCHEMATIC DIAGRAM – MAIN Board (2/3) – • • See page 30 for Waveform. See page 30 for IC Block Diagram. (Page 26) BOARD (Page 26) (Page 28)
CDX-848X Ver 1.1 2001.05 6-10. SCHEMATIC DIAGRAM – MAIN (3/3)/SWITCH Boards – • • See page 30 for Waveforms. See page 30 for IC Block Diagrams. (Page (Page (Page 29) (Page 27) SUB BOARD (NOT SUPPLIED: See page 3)
6-12. SCHEMATIC DIAGRAM – JACK/DIGITAL OUT Boards – • See page 21 for Circuit Boards Location. JACK FLEXIBLE BOARD MAIN BOARD CN301 (Page 24) (Page 28) CN701 R701 C701 (11) 1-679-418- (11) 1-679-420- IC701 DIGITAL SW701 DIGITAL ANALOG ANALOG OUT 1-679-420- (11) CONTROL (FOR SONY BUS)
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CDX-848X • Waveforms • IC Block Diagrams – RF Board – – MAIN Board – –RF Board – 1 IC101 qh (FE) (CD play mode) 1 IC101 rd (MDP) (CD play mode) 5 IC201 ia (X1) (CD play mode) IC101 CXA2581N-T4...
Serial data reading clock signal output to the CXD3027R (IC101) SENS Internal status signal (sense signal) input from the CXD3027R (IC101) BUSON Bus on/off control signal input from the SONY bus interface (IC302) “H”: bus on Battery detection signal input “L”: battery on BUCHK...
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70 to 74 Two-way data bus with the S-RAM Not used (open) RAMIO3 System reset signal input from the SONY bus interface (IC302) and reset signal generator (IC303) RESET “L”: reset For several hundreds msec. after the power supply rises, “L” is input, then it changes to “H”...
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CDX-848X Pin No. Pin Name Description Save end detect switch (SW2) input terminal SAVE SW “L”: When completion of the disc save operation Chucking end detect switch (SW1) input terminal LOAD SW “L”: When completion of the disc chucking operation...
CDX-848X SECTION 7 EXPLODED VIEWS NOTE: • -XX and -X mean standardized parts, so they • Items marked “*” are not stocked since they The components identified by mark 0 or dotted line with mark may have some difference from the original are seldom required for routine service.
CDX-848X 7-5. MECHANISM DECK SECTION-4 (MG-251B-137) not supplied M102 not supplied M101 not supplied The components identified by mark 0 or dotted line with mark 0 are critical for safety. Replace only with part number specified. Ref. No. Part No.
CDX-848X SECTION 8 DIGITAL OUT JACK ELECTRICAL PARTS LIST MAIN NOTE: • Due to standardization, replacements in the • Items marked “*” are not stocked since they The components identified by mark 0 or dotted line with mark parts list may be different from the parts speci- are seldom required for routine service.
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CDX-848X Ver 1.1 2001.05 MAIN Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark C302 1-164-156-11 CERAMIC CHIP 0.1uF IC301 8-759-527-33 IC LB1930M-TLM C303 1-164-156-11 CERAMIC CHIP 0.1uF C304 1-164-156-11 CERAMIC CHIP 0.1uF IC302 8-759-829-46 IC BA8272AFV-E2...
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CDX-848X MAIN Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark R404 1-216-833-11 METAL CHIP 1/16W < IC > R405 1-216-833-11 METAL CHIP 1/16W R406 1-216-833-11 METAL CHIP 1/16W IC101 8-752-089-74 IC CXA2581N-T4 IC201 8-759-832-99 IC LA6576L-TE-L...
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CDX-848X SWITCH Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark 1-679-419-11 SWITCH BOARD PARTS FOR INSTALLATION AND CONNECTIONS ************* ************************************** < SWITCH > 3-040-583-21 BRACKET (T) * 502 X-3369-824-1 SCREW ASSY SW801 1-692-431-21 SWITCH, TACTILE (Z) 1-790-455-21 CORD, CONNECTION (RCA PIN CORD 5.5m)
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CDX-848X US Model AEP Model SERVICE MANUAL UK Model Ver 1.2 2001.06 SUPPLEMENT-1 File this supplement with the service manual. Subject: Change of RF/LSW boards (ECN-CSA04819) In this set, RF/LSW boards have been changed in the midway of pro- duction.
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CDX-848X NOTE FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS Note on Printed Wiring Board: Note on Schematic Diagram: • All capacitors are in µF unless otherwise noted. pF: µµF • Y : parts extracted from the conductor side. • : Pattern from the side which enables seeing.
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CDX-848X SCHEMATIC DIAGRAM – RF/LSW Boards – The components identified by mark 0 or dotted line with mark 0 are critical for safety. Replace only with part number specified.
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CDX-848X ELECTRICAL PARTS LIST NOTE: • Due to standardization, replacements in the • Items marked “*” are not stocked since they • CAPACITORS uF: µF are seldom required for routine service. parts list may be different from the parts speci-...
CDX-848X REVISION HISTORY Clicking the version allows you to jump to the revised page. Also, clicking the version at the upper right on the revised page allows you to jump to the next revised page. Ver. Date Description of Revision 2001.06...