Symbol LS7708 Product Reference Guide3-6
Troubleshooting

If after performing these checks the symbol still does not scan, contact the distributor or call the Global

Customer Interaction Center. See page xvi for contact information.

Problem Possible Causes Possible Solutions
The omni-line scan pattern does not
display when following the directions for
installing the host cable on page 1-5.
No power to the scanner. Ensure the host has power and is on. If the scanner uses a separate
power supply, ensure it’s connected to a working AC outlet.
Interface cable is not properly connected. Check for loose ca ble connections.
Scan line(s) display, but bar code cannot
be read.
Scanner is not programmed to read the bar
code type.
Ensure scanner is programmed to read the bar code type being scanned.
Bar code is damaged. Try scanning other bar codes of the same bar code type.
Bar code is too far from scanner. Move the bar code closer to the scanner.
The host has disabled scanning or
overridden parameter settings.
See the technical person in charge of scanning.
Bar code is decoded, but not transmitted
to the host.
Scanner is not programmed for the correct
host type.
Scan the appropriate host type bar code.
Scanned data is incorrectly displayed on
the host.
Scanner is not programmed to work with
the host. Check scanner host type
parameters or editing options.
• Ensure proper host is selected.
• For RS-232, ensure the scanner’s communication parameters match
the host’s settings.
• For keyboard wedge, ensure scanner is programmed with the correct
country code and that the CAPS LOCK key is off.
• Ensure editing options (e.g., UPCE-to-UPCA Conversion) are properly
programmed.
Although the green and red Power LEDs
are on, the scanner does not produce the
omni-directional scan pattern.
Scanner has gone into Low Power “Motor
Sleep” Mode.
Press the Volume Control & Wakeup button to awaken the scanner.
USB or Synapse host not functioning
properly.
Scanner does not recognize host. Remove and reinsert external power supply to force cable to autodetect
correct host.
An error occurs when connecting to a USB
host.
Cables were installed in the incorrect order. See Connecting the Host and Peripheral Cables on page 1-6 for the
correct order of insertion.
Handheld scanner does not power on. External power supply is not attached. Connect an external power supply directly to the scanner, not to the host
cable.
Auxiliary RS-232 device data is not
received properly.
External power supply is not attached. Connect an external power supply directly to the scanner, not to the host
cable.
Auxiliary device supplies TTL level RS-232
signals.
Use a device that supports standard RS-232 signal levels.
Auxiliary settings are incorrect. Use auxiliary RS-232 port settings, not the RS-232 host settings.

Note