Middle of the night phone calls from tenants are not fun. I know because I received one last night from tenants saying that half of the house wasn't receiving any electricity.
It was 12:45am and I honestly don't even remember even answering the phone call in my sleepy delirium. Slowly I came to while the tenants were panicking that none of the outlets or the lights in the bedrooms worked.
My first response is always to ask if this is something that can wait until morning. My definition of an emergency call apparently is different from these tenants because they were concerned that they wouldn't be able to charge their cell phones.
Next I asked if they had tried flipping the breaker. No luck and the next thing I know I'm in the car headed to the house to double check the breaker for them. It was a rookie move and I kick myself now that I am thinking clearly for caving in without fully thinking the problem through. I do that because this is actually a common problem when you're managing rentals.
I remember the first time I ran into this problem. A bathroom vent fan wasn't working for a tenant and I went as far as buying a new motor for a specialty vent fan only to find out that solution didn't work either.
Nine times out of ten I have found the culprit is a GFCI outlet that needs to be reset. These are the outlets commonly found in kitchens and bathrooms that have a test and reset button. I've encountered GFCIs that aren't even on the same breaker that have been the cause of the problem.
Low and behold this was the solution to our late night electrical problem. Had my brain been working properly I would have been able to handle all this over the phone and avoided the 20 minute round trip in the middle of the night. Oh well. You live and learn and hopefully you can avoid this problem when it arises. If this solution doesn't work then you'll want to resort to having your electrician come out.