AVR 75 (serv.man3) - Harman Kardon Audio User Guide / Operation Manual. Page 34

Troubleshooting

32

AVR75 120   rev (c) 8/27/97

No front panel lights when power

switch is pressed

Display lights, but no sound 
or picture

No sound from any speaker. 
Light around power switch is red

No sound from surround or 
center speakers

No On-Screen Control Menus

Unit does not respond to 
remote commands

Intermittent buzzing in tuner

• No AC Power

• Intermittent input connections

• 

is on

• Volume control is down

• Amplifier is in protection mode 

due to possible short

• Amplifier is in protection mode 

due to internal problems

• Incorrect surround mode
• Input is monaural
• Incorrect configuration

• TV input is S-Video

• Weak batteries in remote.
• Remote is in 

position

• Remote sensor is obscured

• Local interference

• Make certain AC power cord is plugged into 

a live outlet.

• Check to see if outlet is switch controlled.

• Make certain that all input and speaker connections 

are secure.

• Press 

button.

• Turn up volume control.

• Check speaker wire connections 

at receiver and speaker ends for shorts.

• Contact your local Harman Kardon service depot.

• Select a mode other than Stereo or Monaural.
• There is no surround information from mono sources.
• Check configuration in 

SET UP MENU 1

.

• Change TV connection and input to Composite Video.

The menus are available ONLY on Composite Video.

• Change remote batteries.
• Slide 

switch to 

.

• Make certain front panel sensor is visible to remote.

• Move unit or antenna away from computers, fluorescent

lights, motors or other electrical appliances.

Memory Backup
This product is equipped with a memory
backup system that preserves tuner pre-
sets and system configuration informa-
tion if the unit is accidentally unplugged
or subject to a power outage. This mem-
ory will last for approximately one week,
after which time all information must be
re-entered.

System Reset
In the rare case where the unit’s opera-
tion or the displays seem abnormal, the
cause may involve the erratic operation of
the system’s memory or microprocessor.

To correct this problem, first unplug the
unit from the AC wall outlet and wait at
least three minutes. After the pause,
reconnect the AC power cord and check
the unit’s operation. If the system still
malfunctions, a system reset may clear
the problem.

To clear the entire system memory of the
unit, press and hold the 

%

and

^

buttons until 

CLEAR MEMO

appears in the front panel display.
Release the buttons and note that the
unit will turn off and then on.

Remember that once you have cleared
the memory in this fashion it will be
necessary to re-establish all system
configuration information and tuner
presets.

If the system is still operating incorrectly,
there may have been an electrostatic
discharge or severe AC line interference
that has corrupted the memory or
microprocessor.

If a reset does not solve the problem,
consult an authorized Harman Kardon
service depot.

AVR75 om (c)  9/16/98 11:33 AM  Page 32