1) You report that your tank-type electric water heater has lights on the controller.
Please look at label on side of tank to get brand and type of water heater.
Add a comment with all information you have, including description of product.
This will let expert possibly find a manual, and read manual alongside you to assist as you fix water heater yourself.
Keep in mind that expert cannot see your water heater, and that many things cause water heaters to malfunction, and that troubleshoot section of product manual is good place to start.
2) Search manufacturer's website for product manual so you can fix water heater yourself.http://waterheatertimer.org/Water-heater-manufacturers.html
3) If you have electric water heater and don't want to add a comment with identifying information, then look at following page for do-it-yourself troubleshooting:http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html
4) If you have energy smart water heater, you can access information and manual at following link, and possibly fix water heater yourself:
Product manual link shows on page, and gives phone number.http://waterheatertimer.org/Whirlpool-Energy-Smart-electric.html
5) If you do not have tools or know-how to fix water heater yourself, then call a plumber.
Plumbers are expert at fixing water heaters.
6) Post question of professional water heater forum, to double check anything a plumber, friend, or fixya expert says:http://www.thetankatwaterheaterrescue.com/forums/forum3/
7) Add a comment for more free help.
Also take advantage of fixya phone service.
For a price, expert speaks with you over phone while you work on water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.