I live in a townhouse and I was changing my smaller downstairs bathroom lighting.I took old one down and painted bathroom when I went to put new light up I had no power to the exhaust fan and light but the outlet that's in the bathroom works.I think it's the breaker is bad but when I look at them the one that's marked for bathroom turns that outlet off when I switch it off but there isn't another breaker to switch for just the fan or light.
First I checked all breaker by switching them all off and on and making sure their all on then I checked all the outlets with the little breakers built into them there's only 3 of them and I checked all of them and they were good.So I have no power for exhaust fan and light but power to the outlet in small downstairs bathroom.
I am trying to put this place on the market and have to get that fixed before I start having open houses.
In need of some help thank you.

In need of some help thank you.
If you did not change any wiring at the switch, and as you did not mention problems earlier, the problem has to be located in the wiring box above your light point.
From that box there are two wires to your light switch (a hot and a switch wire), and two exiting wires to your light (the switch and a neutral wire).
There should also be at least 2 wires to the fan (a hot and a neutral + possibly a ground).
Most probably one of the connecting wires does not make a proper contact.
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What would makes you think the breaker is bad? This is a rare occurrence, especially if there were no problems before.
What happened in the time between removing the light and re-installing it? Other than painting.
I suspect there is a GFI somewhere that is tripped. You say the receptacle in the bath works? How do you know?

You need a tester to check the wiring at each box. You need to check for power at the switch box first and go from there.
Do you have a tester? I mean something that can tell you the voltage, not just a blinker/beeper to tell if there is power there.

What would makes you think the breaker is bad? This is a rare occurrence, especially if there were no problems before.
What happened in the time between removing the light and re-installing it? Other than painting.
I suspect there is a GFI somewhere that is tripped. You say the receptacle in the bath works? How do you know?

You need a tester to check the wiring at each box. You need to check for power at the switch box first and go from there.
Do you have a tester? I mean something that can tell you the voltage, not just a blinker/beeper to tell if there is power there.

Well I'm not sure if it's bad or not it's just what some people I've asked have told me.
Nothing happened in between the time of removing it and trying to install new one, was actually painting and tried to turn on exhaust fan because of paint fumes and realized it wasn't working.
I've checked all the GFI switches and none of them were tripped.
Ya I guess I'll have to get a tester I did use one of those blicker/beeper and it showed me there wasn't any power at the light switch or the light it self.
I have a lamp in there plugged in for light that's how I know the outlet works but nothing else.

I agree that wires came loose in light box, If light and fan were switched together, switch leg may be disconnected.
If they were switched seperatly then maybe a neutral came undone or Hot supplying switch came undone.
New GFI's Can't reset without power, Does GFI Trip and reset?

I'm not sure what is wrong the GFI does reset and the outlet does have power but just the light and fan don't.They are separate there is a switch for the fan and one for the light.

If you only worked on one box, problem is likely there.

Remove the switch from the box, don't unwire it, just pull it out so we can see it and post a picture.