B&G ZM Series, User Manual

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Troubleshooting tips  |  

ZM Series User Manual

Troubleshooting tips

Issue

Possible Cause

No picture - red LED ON

LED on continuously indicates no (compatible) video is available 
on currently selected source;

Confirm that the correct video input is selected

Check that the video signal cable is properly connected to the 
display. Test cable with ‘known good‘ equipment

Check display settings of the video source - ensure the 
resolution is supported by the display

Ensure brightness is turned up to a suitable level

No picture - red LED OFF

Make sure power is connected to an appropriate  DC voltage 
source, and that the fuse is fitted or breaker is switched on. After 
pressing power button, the red LED should blink as monitor 
starts up, followed by momentary display of the logo on the 
screen. 

Image persistence

Image persistence occurs when a ghost of an image remains 
on the screen after the screen image has been changed. Unlike 
a CRT monitor, an LCD monitor’s image persistence is not 
permanent. To erase an image ghost, turn the monitor off for 
several hours.  To avoid this condition, do not leave the monitor 
displaying the same image unnecessarily, for an extended 
period of time

Picture quality & image 
stability

Check for video cable condition; is shield intact, and does cable 
not exceed maximum distance for video standard

Check the signal source is outputting a compatible resolution at 
a supported frequency

Monitor may be receiving incorrect/bad sync signals from 
source

Video compromised by interference from other equipment

Low level backlight

Supply voltage has dropped below 10V. Will restore at >11V

Unit has been subject to excessively hot direct sunlight for an 
extended period and/or unit enclosure is too hot. Automatic 
thermal protection has been enabled

Slight distortion in text 
or graphics

Not working in native resolution, where possible adjust the 
video source to output correct resolution 

Display is present but 
“bars” appear or roll 
across screen 

Ground loop problem between video source and monitor

Video compromised by interference from other equipment

Vertical shaded bars on 
screen image 

Incoming video may be in 4:3 ratio, either leave in ‘aspect’ mode, 
or set to ‘fill’ to use full screen space. 

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