See the Auto electrical repair tools page for a voltmeter, test light and other helpful diagnostic tools. There could even be a puddle of liquid under the front of the vehicle. 1. I have not checked the actuator, but when you turn the heat on in the car, it is warm for about ten seconds then gets cold again. The blower motor pulls quite a bit of power when working, about 35 amps, the fuse will likely be a large amperage 40A or so. Locate the blower motor fuse, likely a 30 or 40 amp, it may be marked on the fuse box cover or in the driver’s manual. This is an easy fix once you find the bleed port or bleed screw after the fan kicks on while the engine is … How to check the blower motor fuse? A car heater system is essential during the winter or early in the morning when you need to heat your car for that comfortable ambience to work. With thousands of locations across the country, weâll get you back en route to your holiday getaway in no time! In case, there can be a low coolant level which can happen because of some leakage or a severe issue, i.e. What You Should Know, What Are Brake Shoes & How Are They Different From Pads, How to Know When to Replace Your Car Battery, Why Advanced Driver-Assistance Systems Require Special Alignment. The coolant return heater hose should be slightly cooler than the coolant supply heater hose. If it’s broken, the fuse is blown. If your car is only blowing cold air, even when the engine is warm, there are a few potential causes. Faulty heater cores and low or contaminated coolant levels often come hand in hand, and both issues may lead to your engine overheating and your heater not blowing hot air. You can check out my favorite bidirectional tool on the Auto electrical repair tools page. This site is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. Break open the heater box and clean it out completely. The reason why I said sometimes is because it stopped working for a day then it would work again the following day. Situation, we have a friend that owns a 2017 Chevy Trax LT, she is a nurse who works with my wife, single mom and on a single mom budget. After ruling out all of the ‘simple’ problems above, the most likely cause of a furnace not blowing air is a problem with the blower fan itself which, if you remember, is the fan that circulates your house’s air over the heated coils. Checking the resistor is like any other controller, check power and ground, signal inputs and outputs. Check Your Furnace Blower Fan. A c ar heater blowing cold air could be a symptom of the failure of the heating unit. This fluid moves through the heater core, a fan moves air over the warm heater coils blowing warm air out to the cars cab. A misfiring engine is the most common engine complaint and the coil is always the number one suspect. Top 4 reasons car heater blower stops working: Heater blower fuse blown Car heater not blowing hot air? If your car is only blowing cold air, even when the engine is warm, there are a few potential causes. The most common problem, a car heater blowing cold air and overheating / a car heater blowing cold air is the low coolant level. Not having a working heater in your vehicle could even become a dire situation, if you end up stranded. Ive tried flushing it out, the heater core isnt leaking either. It just blows warm air if drive for more than 15 minutes at a time. If indeed your fuse is blown and you replace it only to find it blows again, you may have a blower motor restriction (check for tree fall in the fan blades) or a short in the wiring or more likely a faulty blower motor. A good working car heater isn’t a luxury, it’s critical to staying alive. Yikes! Fixing this can be as simple as a fluid flush. © 2021 Firestone Complete Auto Care. Relays are small electromagnetic units that are commonly located inside the fuse box. Minimum Air Temperature at Floor Outlet 52.2° C (126° F) 56.1° C (133° F) 59.4° C (139° F) 62.2° C (144° F) If the floor outlet air temperature is too low, Both of the heater hoses should be hot to the touch. I have a 2001 Dodge Stratus. With the ignition and fan speed set to high, first try the wiggle test, wiggle the wire to eliminate a bad connection. Hi, I have a Honda civic 2011. It was working in the morning fine, but in the afternoon I was having issues. When your car is quipped with the standard heater system or if it is not equipped with an automatic temperature control system, this kind of problem is an indication of a heater control valve that is not opening. CAR BLOWS HOT AIR ON ONE SIDE COLD ON THE OTHER SIDE. Car Heater Blowing Cold Due to Cooling System Issue Old cars are more than metal and paint, they’re time travelling memory machines. The supply line to the heater core is hot as is the bypass. All of Your Pennzoil Questions, Answered, Let the Miles Roll: 18 Romantic Road Trips for Two, Hereâs What Can Happen If You Let Your Car Sit Too Long, 10 Ways to Make Your Car More Eco-Friendly. Assuming the wiggle test didn’t work, go ahead and remove the two pin blower motor connector. Guide with pics, link to OBD Won’t Connect To ECU - Solved. Looking for the thermostat I found a weird piece on top of engine called a coolant outlet housing, has a bleeder valve on top. Other signs of a faulty heater core include a sweet-smelling scent in your car, windows that become particularly fogged-up, and puddles under the dashboard or on the passenger-side floorboard. Some cars are easy, you look under the dash and there it is. Best Winter Drives in Each Region of the USA, Bridgestone to Give Additional $760,000 to Boys & Girls Clubs COVID-19 Efforts, What is Carb Dayâ at Indy 500â? Before replacing Heater Control Unit, it would only blow hot air from front vents- With this replacement it will now change from cold to hot and the air flow pressure does change from the front vents when changing the setting dial but there is still no air at all to feet and defrost. Modern cars carry a ton of electrical consumers which all need a fuse, the point is your vehicle will have a ton of fuses in two or more fuse boxes located inside and under the hood. The heating system can also blow cold air if there are big air bubbles in the coolant fluid. If the heater is blowing cold air and the car is overheating, it is likely that the problem is related to the engine cooling system as well. link to Where Is My Ignition Coil Located? The resistor is commonly mounted to the fan housing close to the blower motor fan. Thermostat. The outlet is warm, but not hot. Heater not blowing is no joke, I lived and worked as a mechanic in Canada for a time and nothing could have prepared me for the winters. There are many reasons your car's heater isn't working. However, when the blower fan is not working correctly, you may notice little to no airflow coming from the vents. Hooking up the scan tool only to be greeted with no communication is frustrating!!! The heater core may also leak coolant. With the engine running, use a screwdriver to turn the bleed port anticlockwise to expel excess air. I will show in this video. We will need a voltmeter or basic test light. Either the blower isn't working, in which case you may get warm air but not much of it, or it is blowing air but it may not be very hot.