If you have no heat at all but the controls work on the o2 gallant?

1. Why is my car blowing cold air when the heater is on?
2. How do you troubleshoot a car with no heat?
3. What causes a heater not to heat?
4. Is there a fuse for the heater in my car?
5. Why is cold air coming out of my vents when the heat is on?
6. Can a bad radiator cap cause no heat?
7. Can a blown fuse cause heater not to work?
8. Could a bad water pump cause no heat?
9. Why would central heat stop working?
10. Why does my heat only work on emergency heat?
11. How do I know if my heater fuse is blown?
12. What fuse controls the heater fan?
13. Why does my AC work but not my heat in my car?
14. Will thermostat open with radiator cap off?

Why is my car blowing cold air when the heater is on?

Low Coolant Level

The coolant (usually a mixture of water and antifreeze) in your engine doesn't just work to keep the engine from overheating: It's also the source of heat supporting the heating system. If there isn't enough coolant in your system, the heater core will blow cold air into your car.

How do you troubleshoot a car with no heat?

First, check your coolant level to be sure there is enough liquid in there to even get to your heater core. If your radiator is very low on coolant, you'll get no heat. If your levels are okay, you either have a bad water pump or a thermostat that isn't opening.

What causes a heater not to heat?

Often, the issue is that the heating system is simply dirty. ... The system's heat exchanger cannot work unless there's sufficient air moving across it to stop it from overheating. In short, a dirty blower can cause the heat exchanger to fail. Dirty air filters could also be the reason your heater stopped working.

Is there a fuse for the heater in my car?

Q: Is There a Fuse For The Heater In My Car? A: Your car's heater does indeed have a fuse. ... You'll need your car's dusty manual to find out where your fuse box is and which fuse is for the heater.

Why is cold air coming out of my vents when the heat is on?

Your Air Filter Is Dirty

Clogged air filters could be causing cold air to blow out of your vents. A dirty air filter can block airflow over your furnace's heat exchanger, which can cause it to overheat.

Can a bad radiator cap cause no heat?

What is this? If you're wondering whether a bad radiator cap can cause overheating, the answer is a definite yes. Air pockets in the cooling system from an ineffective seal (such as one in a bad radiator cap) or a lack of sufficient pressure can cause the engine to overheat.

Can a blown fuse cause heater not to work?

Fuses. A blown fuse is a symptom not a cause. ... Always use a replacement fuse with the same amp rating as the original. If a new fuse blows as soon as the blower is turned on, the heater circuit or motor may have a short that should be investigated.

Could a bad water pump cause no heat?

Yes, a bad water pump can cause no heat. This is because the water pump is what circulates the coolant through the engine and heater core. If it has failed, it is unable to pump the coolant properly, resulting in little to no coolant circulating through the vehicles heater core causing no heat.

Why would central heat stop working?

If your heater isn't distributing heat evenly throughout your home, the problem is likely one of two things: dirty air filters or inadequate ductwork. Check your air filters and change them if needed. If the filters are clean or if replacing them doesn't do the trick, you may need to inspect your ducts for leaks.

Why does my heat only work on emergency heat?

You should only use your heat pump's emergency heating mode when it's truly an emergency (e.g., your heat pump isn't working in winter) because manually overriding your system means it won't run as efficiently as it can—which will result in higher energy bills.

How do I know if my heater fuse is blown?

You may also need to use your multimeter to check if your fuses are blown. You can quickly determine by checking resistance with a multimeter. A good fuse will have nearly zero ohms of resistance, if the fuse is blown there will be no reading.

What fuse controls the heater fan?

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. What is this? Use a test light or voltmeter to check for power at the blower motor fuse with ignition and blower motor on.

Why does my AC work but not my heat in my car?

If one or more of these issues is present, your vehicle may blow out cool air rather than heat: Not enough coolant in the engine. Problems with the heater core. Clogged or broken heating controls.

Will thermostat open with radiator cap off?

It does. It circulates through just the engine block until the thermostat opens. Then after opening it will flow through the block and the radiator. Fluid in the radiator should not move when the thermostat is closed.