2000 Pontiac Sunfire heater fan not blowing. I took it to the mechanic and he replaced the resistor and it worked for 2 days and then blew the 30amp fuse. He said he then removed the blower completely and put a new fuse in and it still blew the fuse. He is at a loss. Any suggestions?

If the 30amp blower fuse has power, and you can run power to the blower motor and it runs, I would say its the blower relay or the control switch on the dash. The control switch provides power to turn the blower relay on. The fan switch provides the ground circuit.

Go to a mechanic

hello! I had the same problem with my 2000 Pontiac Sunfire... there might be one of these 2 problems with it.... maybe the Heater Core is jammed and the coolant dosen't flow thru the engine to cool it off, or the water pump is defective.... does the heating works or not? if yes, the water pump is defect, if not, the heater core is jammed, try a ''radiator hose cleaner'' (sold in Napa's or Carquest..) it will act as a kind of ''decloaker''.. if works, good! 15$ solution... if not, replace Heater Core... ~150$

Is the correct type of heater core that use for rear heater?Check fan fix its correct side,or wiring change or return water line is blocked.

it could be a shorted out wire causing it to blow the fuse

In most cases the heater switch has gone bad. I would check eBay or a junkyard, either local or on-line for a used replacement. The next most probable cause would be the blower resistor. Those are usually around $40. or more (new) at a parts store. Again it is more likely the switch. You can remove the old switch and check for continuity in the non-off positions with an ohm meter. Good luck!

problem #2 sounds like you need a blower motor resistor.

Replacing the blower motor resistor on a 2000 Pontiac Sunfire is a bugger of a job!.This project is far easier if you remove the blower fan first. You may be able to do it leaving the fan in, but you have to be an elf with very good eyesight. Tools required: 1/4" driver with a universal and a short 5.5 mm or 7/32" socket. First remove the wiring harness and the visible screw. Here's the tricky part! The rear screw is out of sight, and you have to push the floor liner down to get the socket attached. Once you get the 2nd screw out, simply remove and replace with the new one, reinstall the fan motor and your back in business. Hint: If you are not agile, or you are a large person, remove the front passenger seat. It's only 4 nuts and it will save your back. Good luck and hope this helps, keep me posted be glad to help.

I had the same problem today with my sunfire 96 2.2L and it was the radiator fan that was draining too much amperes and the fuse blew up 3 seconds or less after the fan was turning.... i just change the radiator fan motor and the fan and the fuse are ok!!!!

It's possible that the fan control relay is intermittently sticking causing the fans to run continuously. This can overheat and subsequently blow the fuse. Try replacing the relay and see if anything changes.

Hope this helps.