Your bulb has more than likely failed.
Remove power lead.
Remove and check the bulb to see its condition, they go black burnt with age, also see if you can see element is ok.
Dont touch the glass with your fingers.
Clean filters and same time.
If bulb looks ok then reinsert back into your projector and tray again.
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Question edited for full 'make model (what it is)', optima to Optoma
Question moved from Televisions category.
You can only change the password if you know the old one. They are password locked to prevent theft. Any on the secondhand market are stolen from workplaces.
To perform a hard reset on an Optoma UHD55 projector, you will need to locate the reset button on the projector. This button is typically located on the back of the projector, near the power cord. Press and hold the reset button for at least 10 seconds, or until you see the projector's LED light begin to blink. Release the button and the projector will reset to its default settings.
Hi,
please check the serial number of the fans that are supposed to be the same. They might be different in some way because otherwise, the error should not have occurred. If the products have the same serial number or similar type of id, then I would take the projector to geeksquad/bestbuy to double check that the new fan was installed properly.
Thank you.
Reset instructions according to this
https://factory-reset.com/wiki/Optoma_Service_Menu
Optoma Service Menu Instructions
Most of our Optoma Service Menu methods require the use of an original remote, typically you can not do it with just the buttons on the front of the set. If you no longer have your remote or have damaged it, we recommend that you purchase a Optoma Remote before trying to enter the service menu.
Method 1
it may just need a service, as all DLP projectors need to be cleaned internally as well as LCD.DLP projector images will flicker and lose colour also may shut down if it is very dusty inside.