JVC KDR440 CD RECEIVER, HOW TO ENTER SERVICE MODE AND SERVICE ADJUSTMENTS, SCHEMATIC DIAGRAM

KD-R440J, KD-R440JW, KD-R441E, KD-R441EN, KD-R441EU, KD-R441EY, KD-R442E, KD-R442EN, KD-R442EY, KD-R443E, KD-R443EN, KD-R443EY, KD-R444UI, KD-R445U, KD-R445UN,
KD-R446EU, KD-R446U, KD-R446UN, KD-R446UP, KD-R446UT, KD-R447EE, KD-R449E, KD-R449EE, KD-R449UR, KD-R540J, KD-R541E, KD-R541EN, KD-R541EY, KD-R547EE

Service Test mode

Default status immediately after the mode activation
Operating Key: [MENU] + [ |<< ] (7sec) Press and hold.

How to release each Test mode
• Reset
• Acc off
• Power off
• Panel Detach

Mode content
Syscon shall display the following information after entering this mode. The operation shown below shall be workable.

Service Information Clear Mode

Default status immediately after the mode activation
* The receiver is connected with the DC power supply (with the power supply turned off).
Operating Key: [BACK] + [POWER] Press and hold + DC power supply turned ON

How to release each Test mode
• Reset
• Acc off
• Power off
• Panel Detach

Mode content
After entering this mode, Syscon shall clear the information stored for service and output the result to the display tube.
CD will be ejected upon process ended.
Preset Frequencies and Tagging (HD models) information shall be cleared.

DC error information mode

Default status immediately after the mode activation
* The receiver is connected with the DC power supply (with the power supply turned off).
Operating Key: [MENU] + [ >>|] Press and hold + DC power supply turned ON

How to release each Test mode
• Reset
• Acc off
• Power off
• Panel Detach

Mode content
Syscon shall display the following information after entering this mode. The operation shown below shall be workable.

DC offset error description

DC offset detection circuit design
• Purpose:
To prevent breakdown, burning and emitting smoke from customer's car speaker when occur DC offset between speaker output "+" and "-".
• Target:
Detect DC offset, then stop the Power Amp operation and shift to specified condition.

Possible causes of DC offset at speaker output lines
(1) Mis-connection for speaker output for example touch to car body or battery line.
(2) Current leak of coupling capacitor for Power IC input.
(3) Current leak of Ac-GND capacitor for Power IC Ac-GND.
(4) Capacitor shorted of above parts due to foreign object.

To detect DC offset Error
• Mis-connection
- Short any one speaker out line to GND or Vcc
• Capacitor leak
- Parallel 330kΩ to either any one of coupling cap or Ac-GND cap (to simulate current leakage of capacitor)
- Shorted either any one of coupling cap or Ac-GND cap.

Manipulate after detect DC offset
• If detected error 10 consecutive times, and 10th error occurred in "Mis-connect detection period", judge as "Mis-connect".
• If detected error 10 consecutive times, and 10th error occurred in "Capacitor leak detection period", judge as "Capacitor leak ".
• If detected error 10 consecutive times, and 10th error occurred in "Other detection period" and detected another 10 errors consecutively, then judge as "Other".
• If judge as "Mis-connect". - turn off speaker output.

- display "MIS WIRING" > "CHK WIRING" > "THEN RESET" > "UNIT".
- key access disable except button of Eject, Reset and service mode
- record error in EEPROM "DC1 ERR"
- Set is able to be recovered by Reset button.

• If judge as "Capacitor leak ".
- turn off speaker output.
- display "WARNING" > "CHK WIRING" > "THEN RESET" >"UNIT".
- key access disable except button of Eject, Reset and service
mode
- record error in EEPROM "DC2 #" (# means counter number)
- Set can be recovered by pressing the Reset button before the capacitor leak error counter reach "DC2 4".
After that, only clear the counter back to "0" can recover the set.
• If judge as "Other" (manipulation same as mis-connect)

How to cancel DC offset error

Check to be sure the terminals of the speaker leads are covered with insulating tape properly, then reset the unit.
If an error message does not disappear even after a reset, there is a need for internal repair.

How to clear DC offset error recorded in EEPROM

DC Error Information Mode is started.
[MENU] + [ >>|] Press and hold + DC power supply turned ON
DC1 ERR > [ >>|] Press and hold.> DC1 OK
DC2 1-4 > [ |<<] Press and hold.> DC2 0

SCHEMATIC DIAGRAM

KENWOOD KDC-2023, KDC-2024SA CD RECEIVER FULL SCHEMATIC DIAGRAM, SYSTEM CONTROL IC PIN FUNCTION DETAILS KNOWLEDGE

 Kenwood CD receiver KDC-2023, KDC-2024SA/SG/SYA/SYG, KDC-2094YA/YG, KDC-222/S, KDC-3023

For continued safety, replace safety critical components only with manufacturer's recommended parts.  To reduce the risk of electric shock, leakage-current or resistance measurements shall be carried out (exposed parts are acceptably insulated from the supply circuit) before the appliance is returned to the customer.
 DC voltages are measured with a high impedance voltmeter. Values may vary slightly due to variations between individual instruments and units.

CD mechanism extension cord : WO5-0618-00

CD player schematic.

System microcontroller Destination type list.

Kenwood KDC-2023, 2024A/SG/SYA/SYG, 2094YA/YG, 222/S,3023 MICROCOMPUTER'S TERMINAL DESCRIPTION - MECHANISM MICROCOMPUTER MN6627771KP (X32 : IC2)

Kenwood 2024A/SG/SYA/SYG, 2094YA/YG, 222/S,3023 - MICROCOMPUTER'S TERMINAL DESCRIPTION

Kenwood KDC-2023, 2024A/SG/SYA/SYG, 2094YA/YG, 222/S,3023 COMPONENTS DESCRIPTION

JVC CD RECEIVER KDR446 - HOW TO DISASSEMBLE THE MECHANISM SCHEMATIC PROCEDURE

 

 Applicable to models: KD-R440J, KD-R440JW, KD-R441E, KD-R441EN, KD-R441EU, KD-R441EY, KD-R442E, KD-R442EN, KD-R442EY, KD-R443E, KD-R443EN, KD-R443EY, KD-R444UI, KD-R445U, KD-R445UN, KD-R446EU, KD-R446U, KD-R446UN, KD-R446UP, KD-R446UT, KD-R447EE, KD-R449E, KD-R449EE, KD-R449UR, KD-R540J, KD-R541E, KD-R541EN, KD-R541EY, KD-R547EE

DETACHABLE PANEL

KD-R440J	CP-R440JD
KD-R440JW	CP-R440JD
KD-R441E	CP-R441ED
KD-R441EY	CP-R441ED
KD-R441EN	CP-R441ED
KD-R441EU	CP-R441ED
KD-R442E	CP-R442ED
KD-R442EY	CP-R442ED
KD-R442EN	CP-R442ED
KD-R443E	CP-R443ED
KD-R443EY	CP-R443ED
KD-R443EN	CP-R443ED
KD-R444UI	CP-R444UID
KD-R445U	CP-R445UD
KD-R445UN	CP-R445UD
KD-R446EU	CP-R446UD
KD-R446U	CP-R446UD
KD-R446UN	CP-R446UD
KD-R446UP	CP-R446UD
KD-R446UT	CP-R446UD
KD-R447EE	CP-R447EED
KD-R449E	CP-R449EED
KD-R449EE	CP-R449EED
KD-R540J	CP-R540JD
KD-R541E	CP-R541ED
KD-R541EY	CP-R541ED
KD-R541EN	CP-R541ED
KD-R547EE	CP-R457EED

Power Output: 50 W per channel

Continuous Power Output (RMS): 20 W per channel into 4Ω, 40 Hz to 20 000 Hz at less than 1% total harmonic distortion.

Handling the traverse unit (optical pickup)
(1) Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit.
(2) Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific details, refer to the replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a time when attaching it to the connector.
(3) Handle the flexible cable carefully as it may break when subjected to strong force.
(4) I t is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.

Identifying the CD Mechanism

This unit is equipped with one of the two CD mechanism types below.
• FLM-HC3-1D
• FLM-HC5-1D
Before sending the mechanism for repair, please check the following and refer to the corresponding materials.

DISASSEMBLY

Main body (Used model: KD-R441E)

Removing the Bottom chassis (See Fig.1)
(1) Disengage the 7 hooks a engaging the Bottom chassis.
(2) Slide the Bottom chassis backward to remove it.

Removing the Front chassis (See Fig.2)
(1) Disengage the 4 hooks b engaging both sides of the Front chassis.

Removing the Electric unit (See Fig.3, 4 and 5)
(1) Remove the 1 screw A attaching the Top chassis. (See Fig.3)

(2) Remove the 2 screws B attaching both sides of the Top chassis. (See Fig.4)

(3) Remove the 2 screws C and 1 clamp attaching the Electric unit. (See Fig.5)

(4) Disconnect the FFC wire connected to connector CN101 of the CD mechanism. (See Fig.6)

Removing the CD mechanism (See Fig.7)

(1) Remove the 2 screws D attaching the CD mechanism.

Removing the Switch unit (See Fig.8)
(1) Remove the Volume knob.
(2) Remove the 4 screws E attaching the Rear cover.
(3) Disengage the 12 hooks c engaging the Rear cover.

CD mechanism assembly section

Removing the Mecha control board
Removing the Mecha control board
(1) Solder the short land on the pickup. (See Fig. 1)

(2) Remove the 8 wires from the Mecha control board. (See Fig.2)

(3) Disconnect the flexible wire from the pickup connected to the connector CN102 on the Mecha control board. (See Fig.3)
(4) Remove the 2 screws A attaching the Mecha control board. (See Fig.3)

Removing the Traverse mechanism (See Fig.4, 5)
(1) Remove the 5 springs from the traverse mechanism. (See Fig.4)

(2) Remove the 3 screws B attaching the bottom frame assembly. (See Fig.5)
(3) Remove the 3 dumpers from the bottom frame assembly. (See Fig.5)

Removing the Pickup (See Fig.6, 7)
(1) Remove the 2 screws C attaching the feed bracket assembly. (See Fig.6)

(2) Remove the shaft from the TM base. (See Fig.7)
(3) Disengage the hook a on the pickup from the TM base. (See Fig.7)

Removing the Spindle motor (See Fig.8. 9)
(1) Remove the HC CL. Spring from the HC CL. base and the TM base, and then lift up the HC CL. base. (See Fig.8)

(2) Remove the HC CL. base from the holes on the TM base. (See Fig.9)

(3) Remove the 2 screws D attaching the spindle motor. (See Fig.10)

Removing the Loading motor
(1) Remove the roller arm assembly from the bottom frame assembly. (See Fig.11)

(2) Remove the 2 screws E attaching the loading motor assembly, and then remove the loading motor assembly in the direction of the arrow. (See Fig.12)

SONY HCD-D60 SONY HCD-RX70 COMPACT DISC DECK RECEIVER – SERVICE ADJUSTMENTS, SCHEMATICS AND ELECTRIC WIRING DIAGRAMS

  US Model HCD-D60-RX70, Canadian Model, AEP Model, UK Model - HCD-RX70, E Model - HCD-GR7-GR7J, Australian Model - HCD-GR7

  Always respect voltages. While some may not be dangerous in themselves, they can cause unexpected reactions that are best avoided. Before reaching into a powered set, it is best to test the high voltage insulation. It is easy to do, and is a good service precaution.  It makes sense to avoid exposure to electrical shock.  While some sources are expected to have a possible dangerous impact, others of quite high potential are of limited current and are sometimes held in less regard.

Continuous RMS power output

Canadian model:  100+100 watts (8 ohms at 1 kHz, 5% THD)

AEP, German, East European, UK and CIS models:  55+55 watts (6 ohms at 1 kHz, 10% THD)

Other models:  70+70 watts (6 ohm sat 1 kHz, 10% THD)

Peak music power output (GR7-GR7J):  1000 watts

(AEP, German, East European, UK and CIS model):  95+95 watts (6 ohms at 1kHz, 10% THD)

CD Section:

CD Mechanism Type: CDM38-5BD29AL

Base Unit Name: BU-5BD29AL

Optical Pick-up Name: KSS-213D-Q-NP

Tape deck Section:

Model Name Using Similar Mechanism: HCD-H881

Tape Transport Mechanism Type: TCM-220WR2

SPEAKER : 

accepts impedance of 8 to 16 ohms (D60-RX70) 

accepts impedance of 6 to 16 ohms (GR7-GR7J)

SURROUND SPEAKER (US and Canadian models): 

accepts impedance of 16 ohms.
SUPER WOOFER (GR7-GR7J-RX70 : US and Canadian models): 

Voltage 1 V, impedance 1 kilo ohm

The laser diode in the optical pick-up block may suffer electrostatic break-down because of the potential difference generated by the charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also use the procedure in the printed matter which is included in the repair parts.
The flexible board is easily damaged and should be handled with care.

The laser beam on this model is concentrated so as to be focused on the disc reflective surface by the objective lens in the optical pickup block. Therefore, when checking the laser diode emission, observe from more than 30 cm away from the objective lens.

Test mode

[MC Cold Reset]
* The cold reset clears all data including preset data stored in the RAM to initial conditions. Execute this mode when returning the set to the customer.

1. Press three buttons SPECTRUM ANALYZER , ENTER-NEXT , and DISC 1 simultaneously.
2. The fluorescent indicator tube becomes blank instantaneously, and the set is reset.

 [CD Delivery Mode]

* This mode moves the pickup to the position durable to vibration. Use this mode when returning the set to the customer after repair.
1. Press POWER button to turn the set ON.
2. Press PLAY button and POWER button simultaneously.
3. A message “LOCK” is displayed on the fluorescent indicator tube, and the CD delivery mode is set.

 [MC Hot Reset]

* This mode resets the set with the preset data kept stored in the memory. The hot reset mode functions same as if the power cord is plugged in and out.
1. Press three buttons SPECTRUM ANALYZER , ENTER-NEXT , and DISC 2 simultaneously.
2. The fluorescent indicator tube becomes blank instantaneously, and the set is reset.

[Sled Servo Mode]
* This mode can run the CD sled motor freely. Use this mode, for instance, when cleaning the pickup.
1. Select the function “CD”.
2. Press three buttons SPECTRUM ANALYZER , ENTER/NEXT , and FUNCTION simultaneously.
3. The Sled Servo mode is selected, if “CD” is blanking on the fluorescent indicator tube.

4. With the CD in stop status, press >> button in CD section to move the pickup to outside track, or << button to inside track.

5. To exit from this mode, perform as follows:
1) Move the pickup to the most inside track.
2) Press three buttons in the same manner as step 2.

Note:
* Always move the pickup to most inside track when exiting from this mode. Otherwise, a disc will not be unloaded.
* Do not run the sled motor excessively, otherwise the gear can be chipped.

 [Change-over of FUNCTION Name]
* The FUNCTION name of external input terminal can be changed over to VIDEO or MD.
1. Press POWER button to turn the set OFF.
2. Press POWER button together with FUNCTION button, and the power is turned on, the display of fluorescent indicator tube changes to “MD” or “VIDEO” instantaneously, and thus the FUNCTION is changed over.

 

[Change-over of AM Tuner Step between 9kHz and 10kHz]
* A step of AM channels can be changed over between 9kHz and
10kHz.
1. Press POWER button to turn the set ON.
2. Select the function “TUNER”, and press TUNER/BAND button to select the BAND “AM”.
3. Press POWER button to turn the set OFF.
4. Press ENTER-NEXT and POWER buttons simultaneously, and the display of fluorescent indicator tube changes to “AM 9k STEP” or “AM 10k STEP”, and thus the channel step is changed over.

[LED and Fluorescent Indicator Tube All Lit, Key Check Mode]
1. Press three buttons SPECTRUM ANALYZER , ENTER-NEXT , and DISC 3 simultaneously.
2. LEDs and fluorescent indicator tube are all turned on.  Press DISC 2 button, and the key check mode is activated.
3. In the key check mode, the fluorescent indicator tube displays “K 1 V0 J0”. Each time a button is pressed, “K”value increases.  However, once a button is pressed, it is no longer taken into account.
“J” value increases like 1, 2, 3 ... if rotating JOG knob in “+” direction, or it decreases like 0, 9, 8 ... if rotating in “–” direction.
“V” value increases like 1, 2, 3 ... if rotating VOLUME knob in “+” direction, or it decreases like 0, 9, 8 ... if rotating in “–” direction.
4. To exit from this mode, press three buttons in the same manner as step 1, or disconnect the power cord.

[Aging Mode]
This mode can be used for operation check of CD section and tape deck section.
* If an error occurred: The aging operation stops.
* If no error occurs: The aging operation continues repeatedly.

Aging Mode in CD Section
1-1. Operating Method of Aging Mode
1. Set discs in DISC1 and DISC2 trays.
2. Select the function “CD”.
3. Press three buttons SPECTRUM ANALYZER , ENTER-NEXT , and KARAOKE PON/MPX simultaneously.
4. The aging mode is activated, if a roulette mark on the fluorescent indicator tube is blinking.
5. In the aging mode, the aging is executed in a sequence given in “1-2. Operation during Aging Mode”. The aging continues unless an alarm occurred.
6. To exit from the aging mode, press POWER button to turn the set OFF.
* If a button other than buttons In CD section is pressed during aging, the aging in the CD section is finished.

* To execute aging to the tape deck section successively, press > button in the deck A.  “AGING” is displayed on the fluorescent indicator tube. (For the aging in tape deck, see “2. Aging Mode in Tape Deck Section”.

1-2. Operation during aging Mode
In the aging mode, the program is executed in the following sequence.

1. The disc table is ejected.
2. The disc tray turns to select a disc. (For a disc selection sequence, see Section 1-3.)
3. TOC of disc is read.
4. The pickup accesses to the last track.
5. A disc is ejected.
6. Steps 2 through 5 are repeated.

1-3. Disc Selection Sequence
* During the aging mode, discs are selected in the following sequence:

Disc 1 > Disc 2 > Disc 2 < Disc 1 >  [repeats]

2. Aging Mode in Tape Deck Section
2-1. Operating Method of Aging Mode
1. Load a commercially available 10-minute tape into the decks A and B respectively.
(If a 10-minute tape is not available, another tape may be used but a cycle time will be longer.)
2. Select the function “TAPE”.

3. Rewind tapes in advance by pressing <<  button respectively on decks A and B

4. Press three buttons SPECTRUM ANALYZER , ENTER-NEXT , and KARAOKE PON-MPX simultaneously.

5. Press PLAY button on deck A. (This button triggers the aging mode.) button on deck A. (This button triggers the aging mode.)

7. In the aging mode, the aging is executed in a sequence given in “2-2. Operation during Aging Mode”.
The aging continues unless an alarm occurred.
8. To exit from the aging mode, press POWER button to turn the set OFF

2-2. Operation during Aging Mode
In the aging mode, the program is executed in the following sequence.
1. A tape on FWD side is played for one minute.
2. PAUSE STOP is made.
3. Recording is made for 3 minutes. (For the deck not having the record function, the play is executed. In this case, > LED does not light up.)

4. FF is executed up to the end of tape.
5. A tape is reversed, and the tape on REV side is played for one minute.
6. PAUSE STOP is made.
7. Recording is made for 3 minutes. (For the deck not having the record function, the play is executed. In this case, <  LED does not light up.)

8. FF is executed up to the end of tape.
9. Steps 1 through 8 are executed for the other deck.
10. Steps 1 through 9 are repeated unless an alarm occurred.

2-3. Deck Selection Sequence
* During the aging mode, decks are selected in the following sequence:

Deck A (FWD)  >  Deck A (REV) > Deck B (REV) > Deck B (FWD) > [repeats]

PCB locations

Audio board schematic

BD board schematic

Front panel board schematic

Front panel PWB and wiring diagram

Main board PWB and wiring diagram

Main board schematic

Power amplifier board schematic

Tuner section schematic