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Does Your Car AC Keep Blowing The Fuse? (How to Fix)

car ac not blowing

Does Your Car AC Keep Blowing The Fuse? (How to Fix)

During the summer, your car’s air con can be a lifesaver. In fact, it can be pretty hard to live without one. However, car AC also has a tendency to break at the worst times. One of the most common problems with a car AC is that it constantly blows a fuse. If you’re having these issues, then keep reading. Because in this article, we’ll explore the top reasons why your car’s AC keeps blowing its fuse. So, shall we take a look?

The way your car’s air con works is actually pretty interesting. The system works by manipulating a liquid called refrigerant between liquid and gas states. By constantly changing states, the refrigerant is able to absorb the heat in the car and give off cool air.

Most of the parts in your AC are also powered via electrics. As such, if your AC keeps blowing its fuse, it can completely ruin the system. But, what are the causes of this?

Main Reasons your Car AC Keeps Blowing Fuse

The main reasons your car AC keeps blowing its fuse are:

  • A faulty Field Coil
  • A damaged wire harness
  • A damaged compressor clutch
  • Damaged Wires
  • A damaged AC pressure switch

Let’s take a look at each of these problems in a little more detail.

Car AC Keeps Blowing Fuse Due to Faulty Field Coil

A field coil is designed to generate a rotating field as part of the AC’s electric motor. When it’s working optimally, the field coil will have 3-4 amps of current. However, if the field coil becomes damaged, it can start to carry upwards of 10 amps of current.

When this surge of current occurs, your AC’s fuse is likely to blow. This happens most often after a long drive, or if the AC is turned on and off multiple times in one journey.

To check your field coil, use an Amp Clamp to check the current passing through it. If the reading is high, there’s a good chance your compressor will need replacing.

A new field coil is typically under $100. You can fit this yourself, but it is a pretty tricky procedure.

Faulty/Damaged Wire Harness

A wire harness helps to secure all of a vehicle’s wires and cables. It also protects them from damage via vibrations and moisture, ultimately increasing the longevity of your vehicle’s electrical components. It also helps to increase the resistance of the wires in place, lowering the current. Thus, a problem with the wire harness can often lead to several electrical problems, such as your AC’s fuse blowing.

This is one of the most common causes of faulty AC, especially when the issue lies with the fuse. Unfortunately, there aren’t any solid tests that you can conduct to test whether or not your wire harness is damaged.

Your best bet is to see a mechanic. They will quickly be able to check the state of your wire harness, and provide good advice. In some cases, a damaged wire harness may be fixable. However, you’ll normally have to get it replaced. This can cost over $1,000, depending on your vehicle.

Broken Compressor Clutch

A broken compressor clutch is one of the most common reasons why your car’s ac keeps blowing its fuse.

Your compressor clutch can become faulty, or even break, due to continuous high pressure from the AC. When this happens, the compressor clutch stops working properly, causing your fuse to blow.

The best way to fix a broken compressor clutch is to have it replaced entirely. Often, the cost of fixing a broken one can be much higher than buying and installing a new one. Expect to pay the best part of $1,000.

Damaged Wires

Sometimes, the most simple explanations are also the most accurate. If you’re having problems with your AC’s fuse, it’s likely that there is a problem with the wires.

For instance, the wires may not be providing enough resistance, causing too much current to go through the circuit. Alternatively, the copper wires may be touching, due to a lack of insulation, causing a short circuit.

You can test for short circuits by using an amp clamp. If the current is higher than the normal amount, there’s probably an issue with your wires. You can check the optimum current levels for your car by referring to your owner’s handbook.

Wiring can be pretty difficult to repair. If you’re inexperienced, it can also be dangerous. As such, you should take your vehicle to a mechanic to have it fixed. Wiring issues are fairly inexpensive to solve.

Damaged AC Pressure Switch

To constantly switch the state of the refrigerant from liquid to gas, your car ac needs to be able to regulate pressure. If your pressure switch isn’t working, the pressure won’t be properly regulated, leading to extreme pressure.

When your AC pressure becomes too high for too long, the compressor may malfunction, or turn off to prevent further damage. This, in turn, can cause your ac fuse to blow, completely ruining your car’s AC.

Unfortunately, the only way to fix this problem is to replace the AC pressure switch. This is a pretty expensive repair too. Expect to pay at least $500, but potentially more depending on your vehicle.

Still Struggling to Figure out Why your Car AC Keeps Blowing its Fuse?

If none of these solutions work, then there may be an issue specific to your car. It could be something as simple as a piece of metal causing a short circuit, or a common problem with your specific model’s electrics.

The best solution is to see a mechanic for a diagnosis. They will provide a thorough check and give specific advice to fix your problem. Normally, it’ll be much simpler than you think, and probably a lot cheaper too!

Final Thoughts

So, there are all of the main reasons why your car AC keeps blowing its fuse. You should never try to solve the problem by installing a bigger fuse, as this is really dangerous and could lead to serious electrical damage. And, if you ever feel out of your depth, call a mechanic, as they’ll be able to solve the problem quickly and safely.

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