What will happen if EOL is short?

I install fire alarms fairly frequently and have no clue what you are asking. What do you mean by EOl and then maybe I can help. Do you mean end of line resistor?

If this relates to an EOL resistor on a security system and the line is shorted, in a correctly installed configuration, the security system should generate a trouble notice. The security system will expect that the line is to have a specific resistance, but when shorted that resistance would be about zero. Validate resistance is the value of the EOL resistor or infinite (open circuit - usually indicating an alarm for NC / normally closed configurations), not zero. For this reason EOL resistors are always to be installed at the "end of the line" (where the open/close switch is located), not in the security box where many people (including installers) often put them. The idea is that if someone tampers with your system, or you accidentally put a nail through a security wire when hanging a picture, that your alarm system will tell you that your infrastructure is compromised and on what zone.

I install fire alarms fairly frequently and have no clue what you are asking. What do you mean by EOl and then maybe I can help. Do you mean end of line resistor?

That is mean by line end monitoring, means some where cable open can detect in the panel.

If a Fire system, It may be a powered EOL. Meaning, System will show a trouble, if the loop is shorted, open, or power is lost to the detectors.
They also have Double End Of Line Resistors for security.