A few months ago my heater was working, but now it stopped. Does anyone have any ideas of how I can fix this problem?

 

Do you mean the heater doesn't get warm, or the fan doesn't blow? If it's the fan then be sure to look under the hood at the electrical connection and see if it's fallen off the fan motor. Mine did that more than once over the last 38 years! If it's on still, then pull it off and check voltage at the connector to see if it has 12 v. to it.
If it's not getting warm then it could be a plugged core, or a bad control cable.

 

The heater doesn't turn on at all. when I flip the switch to heat nothing happens.

 

Then start with the basics. Check the fuse. After that check as I said at the connector, and the heater motor. A 12v. test lamp is a must for troubleshooting electrical!

 

ok man i was in the same boat. i changed all my fuses first. our camaro are pretty awesome when it comes to the switches. my heater only worked on low.... med. and high didnt work. i got under my dash and pulled the whole switch out of the car. opened up the switch which is i think a single spring and a contact plate and the body which has little copper nubs which are contacts. its supper easy to do.

my contacts where black, 30years of carbon fouling, the contacts where so weak they couldn't deliver the 12vlts to the heater. our switches ran 12vlts though the switch why they are soo huge unlike all the ones on newer cars which deliver 1~4vlts to a relay which delivers the full 12vlts

we replace relays because they carbon foul or foul out regardless.

take a little wire brush and contact cleaner OR non chlorinated break cleaner and clean the whole inside of the switch out. i used a dremal with a wire brush and cleaned it down to a bright new copper surface. it will act brand new. use a drop of oil in the areas that slide but not on the contacts and replace.

i did the same thing to my light pull out switch and even cleaned my dimmer coil. all the switches on our car are some what serviceable IF you know what your doing.

and get a 12vlt tester YOU WILL USE IT.