First, have you checked fuses? That is where I would start. Pic 1 shows the power window fuses. Check them. When you say the heater isn't working, do you mean the blower motor doesn't turn on? If that is the case, you need to check for power to the blower motor relay mounted near the motor itself. There is a white wire that goes to it which should have power. Power is supplied via what is called a fusible link. It isn't a fuse, but functions as one. It looks like a regular wire, but will fail if too much power goes through it.
See pic 2 for fusible link. Pic 3 shows the blower motor relay. It is under the dash near the blower motor. I circled the relay to help.
Here are a few links you may find helpful:
If there is power to the relay, here is a link that shows how to check a relay:
Let me know what you find or if you have other questions
Images (Click to enlarge)
Monday, December 2nd, 2019 AT 8:31 PM