2005 monte carlo ss 3.8 with sc. I just got the car and the heat is out. it will work 1 or 2 days and then be out for a week and one day it will just come on again. i have checked all the fuses and coolant, i have also pluged in a new blower motor and resistor when it went out last time and got nothing i just got a new hvac control unit and got nothing. i can hear the vents changing and the compressor comes on but not the heater fan. i don't want to waste any more money help!

 

Sounds like a fan issue to me....IMO

Maybe someone else will chime in with more ideas.

 

thanks but i have put in a new blower motor (fan) and it did not turn on.

 

what's your temp gauge reading?

 

It might also be the fan control switch itself....???

I know on my silverado...(dont know if its the same on the Montes)
Theres a circuit board that controls the fan speeds...and it could possibly be burnt out. I had to replace it and now the fan works just fine....

Maybe someone else will know if our Montes has the same circuitry.
Its called a blower motor resistor....
Chevy Monte Carlo Blower Motor Resistor - AM Autoparts

 

it is because your ignition switch is bad buy one for 30 bucks on ebay and install it directly behind where your keys goes in. It will shut down your heat ac fan and overhead display this mine shut down my cruise control as well. sometimes it will turn on sometimes it wont but after you put a new one in it hasnt not worked at all. and its cheap and easy to install yourself... just make sure to remember to turn your key to ON and then hit the switch on the cluster and the silver part will slide right out then reconnect the wires and your good to go

 

if you got any questions just ask i just did mine last week haha

 

right in the middle i think it is just under 200

 

did you just go through the radio opening? i looked at some pics is it just the two screws in front that holds it in? and do i have to worry a bout any surcrity things getting messed up i keep seeing people that have issues with that after replacing things.

 

nooo first you have to take off a few panels from the botton there is a plastic one with two clips that popps right off then take off the metal plate than ex ex ex here ill give you a link to a video ... after you get the big piece off then take the two screws infront of the key out then there are 3 or four behind it you have to undo than it should be able to pull right out backwards (as if you were pushing it into the engine) and then down and out the front but there are wires to watch for then 2 plugs to disconnect then turn key to on push the small black button on the back and it will slide out ...
for those who are on the forum that made the vids thanks... the red car i know i have seen oyou on here i just cant remember who it is haha