해당 위키는 저희 교육 프로그램의 멋진 학생이 작성하였습니다. iFixit 직원이 관리하지 않습니다.
JVC KW-V820BT Troubleshooting
This troubleshooting page will help you diagnose problems with the JVC KWV-820BT.
Your JVC device is producing poor quality sound.
Low Fidelity Audio
Be sure that the audio you are playing is high fidelity and the source of the distortion is not a quality of the audio itself. If using the tuner, be sure you have good reception; poor reception could the result of a bad or disconnected antenna. Check the audio source quality or antenna if using tuner.
Be sure the equalizer in the JVC KW-V820BT is configured to “flat”. If using an external audio device (a portable Mp3 player or other external device) be sure check for equalizer filters within the external audio device itself. Default all equalizers to “flat” or “off”. Consult the manual for your specific external audio to manage device equalizer settings.
Active “VoiceOver” on Phone
Check “VoiceOver” features according to the instructions for you phone. Active voice over software can generate feedback interference over sound system. If these “VoiceOver” features are active, deactivate these features. Consult the manual for your specific external audio to manage voice over settings.
Bluetooth Signal Interference
If broadcasting audio via Bluetooth signal, reduce distance between audio transmitter and JVC KW-V820BT audio device.
Unsecured Hardware Near Speakers
This sound is characterized as a rattling sound that resonates at specific frequencies. This may be caused by unsecured hardware (possibly apart from the sound system itself) that is resonating at the sound system. Attempt to isolate the sound by damping vibrations of suspect parts with your hand and secure the hardware.
This type of sound is characterized by a rattling or crunching distortion in the sound, particularly during loud periods in the audio track. This issue may be a result of an overdriven amplifier, reduce the volume on the device that is supplying the audio.
This type of sound is characterized by a rattling or fuzzy distortion, particularly in low frequency band. This issue can be sourced to one or more speakers. A blown speaker can be identified by visible damage to the speaker cone, or torn foam at the edge of the cone. If there is no visible damage, gently press on the outer surface of the speaker cone to verify that there is resistance from the suspension inside the speaker. If no discernible damage is found in the cone, test for continuity across the terminals of the speaker to determine the state of the coil. Use a digital multimeter to measure the resistance across the coil; the resistance should measure 1.0 ohm or less. High resistance across the terminals of a speaker indicate damage to the coil. If it is determined by these tests that the speakers are damaged, remove and replace speakers.
Bad Rectifier on Alternator Circuit
This sound is characterized by a high pitched “whining” sound that does not change with volume control knob, but does change with engine RPM. Locate the diodes in the alternator’s rectifier circuit and check resistance across the leads in both direction, resistance should be very low across one direction and very high across the other. Replace bad diodes if possible, or entire rectifier circuit assembly.
Disk Drive Not Accepting or Ejecting Disks
CDs or DVDs will not correctly enter your JVC device.
Check to be sure the device is powered. If the device is not powered, the device will not accept or eject discs. Check for voltage across power supply terminals with DMM and check appropriate fuses in device and on vehicle fuse panel to diagnose power failure.
Power the device off and then back on again. Press the eject button and wait for the disk to completely leave the drive. If disc still does not eject, attempt to force eject disc according the user manual provided with the device.
Mechanical failure of disk drive
If attempts to forcefully eject disc according to the description above has failed, check for signs of mechanical failure of disc drive. While pressing the eject key, listen for any sounds that might indicate internal mechanical failure. Service the disk drive according to this guide.
No Picture Display on Screen
The JVC screen does not show anything.
Check to be sure the device is powered. If the device is not powered, the the display will not present a picture. Check for voltage across power supply terminals and check appropriate fuses in device and on vehicle fuse panel to diagnose power failure.
If it confirmed that the device is correctly connected, attempt to power the device on and then off again. If the screen still does not present a picture, check for continuity in the connection between the device and the touchscreen display. If display is disconnected, reconnect device according to this guide.
If it is ensured that the display is correctly connected to the device, inspect display for signs of damage. Replace the screen using this guide
No Sound from Speakers
The speakers do not report any sound whatsoever
If there is no sound, check to be sure the device is powered on. If the device is not powered on, connect the device according the instructions provided in the user manual
Fader is not adjusted properly
If the audio device is powered on and there is still no sound, adjust the volume using the fader.
No sound playing
If the device is powered on, and the fader is adjusted to supply audio to speakers, check to be sure you are supplying audio the amplifier. Consult user manual to test available audio inputs.
Speakers not connected
If the device is powered on, the fader is adjusted to supply audio to speakers, and an audio signal is being supplied to the amplifier, check to see that the speakers are connected. Lower the volume fader on the device to avoid sudden loud bursts of audio and check speaker connections at the back of the device. Inspect speakers connections for discontinuity, damage or corrosion. For a quick method to test that the speakers are connected, you may remove the speaker wire from the back of the device and very quickly and very briefly touch the leads of the speaker wire against the terminals of a 9 volt battery; connected speakers will report audible sounds from a 9 volt battery. Otherwise, you can inspect the speaker terminals and the continuity through the speaker wire manually with a digital multimeter.
Remote Control not Functioning
The JVC display is not correctly responding to the commands given on the detached remote.
If the remote isn’t working, reduce distance between remote and device.
If the remote isn’t working, replace the battery or test battery voltage, battery voltage should be above 1.3 volts DC.
Device IR receiver malfunction
If the does not respond to short range remote usage with fresh battery, check to ensure that the remote is transmitting a signal. This can be tested using any digital camera sensor, including ones commonly found in cell phones. Direct the remote sensor into the camera and check for visible light signal from infrared (IR) transmitter at the end of the remote. If the signal is visible to the camera, the IR transmitter is visibly working according to the camera display, it can be inferred that either the remote is not paired properly with the device, or the IR receiver on the device is obstructed or defective.