Friday, January 15, 2016

DENON AVR-4520 INTEGRATED NETWORK AV RECEIVER – Initialization – Special Mode – Firmware update – Diagnostic mode – Idle current adjustment

                                               Category: AV Receiver Repair and Service 

Contents of this article 

  • Initialization
  • Idle current adjustment 
  • Firmware update 


INTEGRATED NETWORK AV RECEIVER initialization should be performed when the μcom, peripheral parts of μcom,
and Digital P.W.B. were replaced.
1. Turn off the power pressing "Power operation " button.
2. Press "Power operation (X)" button while simultaneously while pressing "Cursor UP " and "Cursor DOWN " buttons.
3. Check that the entire display is flashing at intervals of about 1 second, and then release the 2 buttons.
The microprocessor will be initialized.
Special mode setting button
Press the "Power operation (X)" button to turn on the power while pressing both the buttons A and the button B at the same time.
Turn on the power, then press and hold down the A and B buttons for over 3 seconds.
µcom/DSP Version display mode
When the set is started up in this mode, the version information is displayed.
Starting up:
Press the "Power operation (X)" button to turn on the power while pressing the "SETUP" and "OPTION" buttons.
Now, press the "OPTION" button to the display the 2nd item information on the FL Display.
b When the version is displayed on the FL Display, the version list is also displayed on the OS
PANEL/REMOTE LOCK Selection mode
Behavior specifications
In this mode, you can switch between the PANEL LOCK MODE and the Mode for preventing remote control acceptance.
Starting up
Press the "Power operation " button to turn on power while pressing the "STATUS" and "INFO" buttons.
Press the "Cursor UP/DOWN" button to select the mode and the "ENTER" button to confirm the selection.
Mode selection method and how each mode is displayed
Each time you press the "Cursor UP/DOWN" button, the mode displayed on the FL DISPLAY changes.
While the desired mode name is displayed on the FL DISPLAY, press the "ENTER" button. The set is restarted and the selected mode takes effect.
DIAGNOSTIC MODE (Video/Audio (signal) path confirmation mode
This mode is used for confirming the Video and Audio (signal) paths. (Troubleshooting)
Confirming the operation of unit can be easily done after repair.
Backup data will not be lost.
Starting diagnostic mode
Press the "Power operation " button to turn on power while pressing the "ZONE/REC SELECT" and "STATUS" buttons.
Select "1. SERVICE CHECK" and press "ENTER" to start the set in the Diagnostic mode.
In this mode, TUNED, STEREO and RDS are lit in FL display.
DM860A Reboot mode
#  When DM860A is hung up, DM860A is restarted.
Even when Network standby is set (Setup Menu - Network - Network - Always ON), DM860A can be reset.
1. Turn on MAIN ZONE button, and select NETWORK for the input source.
2. Press and hold the "DIMMER" and "INFO" buttons for 3 seconds and longer.
3. DM860A is restarted and returns to the normal display.
When "ZONE4 HDMI mode" is set to "Follow ZONE2", you can use ZONE4 HDMI OUT as ZONE2.
You can assign ZONE2 for Amp Assign to play back speaker audio and HDMI video in ZONE2.
(1) Press the "Power Operation " button while pressing "ENTER" and "INFO" buttons on the set to turn the power on.
(2) After the POWER ON sequence is displayed, FLD displays the indication for the ZONE4 HDMI mode.
(3) Press the "Cursor LEFT"/"Cursor RIGHT" buttons to select the setting.
You can update the firmware by downloading the latest version from the Internet.
How to update by DFW
Preparations before starting the operation
(1) Personal Computer (Installed "DFW_0062_AVR4520_(Rev.x.x.x).exe".
(2) RS-232C cable (9P (Male), Straight).
NOTE : Refer to "The Operating Manual for updating of DENON AV receiver firmware".
Connection of AV receiver
(1) Confirm the power on/off switch of the AV receiver is turning off.
(2) Connect the RS-232C cable from PC with the "RS232C Terminal of AV receiver".
Turn on the AV receiver
Turn on the AV receiver. When the board is replaced, the Flash ROM is replaced, or rewriting fails, always complete the
following steps to force the update.
Forced Update Mode :
(1) Connect the power cable to the AC outlet while simultaneously pushing the "BACK" and "ZONE/REC SELECT"
button of the front panel.
(2) Confirm the power indicator is red.
Communication check
(1) Select the serial port number of RS-232C in PC.
(2) Click the "Check Comm." button.
(3) When connection is good, then you can see the "Communication check OK." message.
(4) If connection is not good, then you can see the "Communication check NG" message.
Please confirm the following
(a) Check the connection of the AV receiver and PC.
(b) Check the operation mode of the AV receiver.
(c) Check the selection of the RS-232C port number of PC.
Download the firmware
(1) Click the "Load" button.
(2) Download the firmware from the specified download source to PC.
Complete the firmware updating
(1) Click the "Update" button.
(2) When writing of the firmware is completed, the power of AV receiver turns on automatically and you can see the
"Update completed" message.
(3) If you can’t complete the firmware update, please retry the firmware update from "1.3. Turn on the AV receiver" (Forced
Update Mode ).
Please keep the following notice for firmware update.
(a) Keep the PC environment
(b) Avoid the communication cable from the electrical noise source.
(e.g. telephone cable, AC line, a fluorescent light)
(c) Don’t remove cable during update.
(d) Don’t turn off the power during update.
(e) Don’t run other PC application during update.
(f) Stop the resident program on PC (Virus checker and System check utility, etc.)
(g) Stop the screen saver on PC.
(h) Stop the power save ability on PC.
(i) In case of laptop PC, Use the AC adaptor.
Adjusting Idling Current
Required measurement equipment: DC Voltmeter
1. Preparation
(1) Avoid direct blow from an air conditioner or an electric fan, and adjust the unit at normal room temperature 15 °C ~ 30 °C (59 °F ~ 86 °F).
(2) Presetting
# POWER (Power source switch) STANDBY
# SPEAKER (Speaker terminal) No load
(Do not connect speaker, dummy resistor, etc.)
2. Adjustment
(1) Remove top cover and set V101,V201,V301,V401,V501,V601,V701,V801,V901 on 9CH AMP UNIT at fully counterclockwise (c) position.
(2) Connect DC Voltmeter to test points (FRONT-Lch: N9039 9pin-10pin, FRONT-Rch: N9040 1pin-2pin, CENTER ch:
N9039 7pin-8pin, SURROUND-Lch: N9039 5pin-6pin, SURROUND-Rch: N9040 3pin-4pin, SURROUND-BACK
Lch: N9039 3pin-4pin, SURROUND-BACK Rch: N9040 5pin-6pin, FRONT-HEIGHT Lch: N9039 1pin-2pin, FRONTHEIGHT Rch: N9040 7pin-8pin.
(3) Connect power cord to AC Line, and turn power switch "ON".
(4) Presetting.
MASTER VOLUME : "---" counterclockwise (c min.)
SPEAKER (Speaker terminal) : No load
(Do not connect speaker, dummy resistor, etc.)
(5) Within 2 minutes after the power on, turn V101 clockwise (x) to adjust the TEST POINT voltage to 8mV ± 0.5mV DC.
(6) After 10 minutes from the preset above, turn V101 to set the voltage to 12mV ± 0.5mV DC.
(7) Adjust the Variable Resistors of other channels in the same way.