- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
More than likely you have an internal fault either in the fan itself or the thermostat that activates it.
For a fuse to blow it has to have a lot higher than normal current draw through it, which is normally refered to as a short. If the fuse blows almost immediately then I would suggest you unplug the fan, and see if the fuse blows with just the thermostat in the circuit. If it blows - replace the thermostat control. If it doesn't blow, plug in the fan and watch it. If it trys to start and then blows the fuse, replace the fan motor.
Note that you will not damage anything unless you don't turn it off when it gets too hot.
So start the car and let is idle to get warm - have the hood open and see if the fans come on. If the temp goes past normal and fans do not kick on, it's usually the fan relay (~$20) - these usually sit in the engine compartment fuse box. Also check the fan fuses - there should be two of them. If that doesn't work, then it would be the temp sensor.
However if your heater is blowing cold when the car is warm, sounds like there is an air-lock. This happens if you don't 'burp' the cooling system properly after flushing the system. Easiest way to check on this is if either the lower or upper radiator hose is not hot when the engine is hot.
Incidentally, if the thermostat is shot, you would not be able to 'burp' the system properly.
My bet is either the thermostat or airlock - or both.
heat sensor for radiator fan switch, thermistat,water pump? Does hot air blow when moving? does car over heat when sitting idling for over 10 minutes. If so check fan first, then water pump. last cause thermisat
After warmup it still blows cold, or only when cold? Normally the fan will operate independently of engine temp except in some climate controlled vehicles. As long as it blows warm air after engine is at temp that's a good thing. the heater uses hot water from the engine. Obviously the heater can't be warm before the engine is. If it's cold after the engine is hot, there are vacuum controlled "motors" on top of the heater box under the dash that move doors that control heat. Either one of the control motors or one of the doors have stuck or failed. Many also have a control valve on one of the heater hoses under the hood as well. If the engine comes up to temp then the thermostat is good (should be at about 210f) Only remaining item is the core itself which may be internally or externally obstructed. All this being said, if it's good when the engine is up to temp, leave it alone...it's fine.
Flush rad & change coolant & thermostat. Check operation of rad fan, & make sure it is coming on when engine reaches normal operating temperature. Be sure to bleed air out good when refilling rad/cooling system. Start engine & turn heater on when refilling & let rad fan come on & off at least 2 or 3 times before putting cap back on rad, and refill rad as needed as you do this. then fill return bottle to proper level & see what happens.
I recently had the same problem with my car. The solution for me was to remove the coolant lines going into the firewall(be sure to let it cool down first)and blow out the heater core with compressed air.I went from blowing barely luke warm air to awesome heat...good luck
I have the same problem with my 2001 Tahoe. The front blower is working, its blowing strong, but its cold air even with the temp setting as high as it can get. The rear blows hot air. The engine temp guage is at about 210ish which is close to being normal (220). I just replaced the thermostate a few months ago, I don't know if its bad again, or it I deluted the antifreeze too much and it frooze the heater core, or if the heater core just went bad. Any one know what the cause could be?
Check blend door motor for proper operation (vacuum operated) if necessary, detach arm from heater box and move by hand. If you have heat then, change motor! You are reaching operating temp for engine, right? If not, thermostat is stuck open... Change.