If you have an Android phone of the right model (I do) there are two (at least) apps that might do it
Not all Universal Remotes are the same.. Some have codes others do not
Finally.. I have a rare brand TV here . Got it cheap cause it had no remote, I found a different make remote that 1: I already owned, and 2: Worked all but the INPUT SELECT function
Then I went on E-bay and got an original remote for 10 bucks.