Should it will ask you for a password. Try “DOTS”, the default password.
In all likelihood, the crew will not have changed it. However if they did, never fear. Hold “Control” and “Shift” and while holding, enter “DIPY”. This will reset the sign and reset the password to “DOTS” in the process. You’re in!
You can also find the manuals for these electronic road signs easily online.
From a 2009 Jalopnik article:
You can also find the manuals for these electronic road signs easily online.