Why AC Compressor Shuts Off After A Few Seconds – 7 Reasons

Air conditioning compressors have played a vital part in almost every vehicle, sustaining your engine’s seamless fluid and refrigerant circulation.

Hence, once your AC compressor shuts off after a few seconds (and on a startlingly frequent basis), ignoring it will be a deadly mistake! 

Instead, we strongly suggest you take more time to assess the problem, find out where it goes wrong, and strive to fix it.

Our detailed guide will serve as a perfect assistant for you guys in this regard – listing all possible reasons behind the AC malfunctioning.

What are you still waiting for? Buckle your seatbelt and dive in with Bryan’s Garage!

Why Your AC Compressor Shuts Off After A Few Seconds

AC Compressor Shuts Off After A Few Seconds

Your AC  compressor comes on then shuts off due to: thermostat problems, wrong thermo positions, unclean oils and filters, oversized air conditioner, refrigerant leakages, compression failure, electrical problems, frozen evaporators, clogged drain lines, and bad capacitors.

1. Thermostat Problems

Thermostat Problems

Is your air conditioning system short cycling in minutes? Chances are things boil down to the thermostat, so check it out right away.

While thermostats seem quite minor compared to the whole system, they take charge of temperature control for the car and hence, call for proper installation and functioning.

When these compartments fail to monitor the temp and transmit wrong info, your compressor shuts off after a few minutes, depleting the battery powers.

For diagnosis of more serious cases, it would be best to reach out to an HVAC repair company.

2. Wrong Thermo Placement

Wrong Thermo Placement

The thermostat screen senses their surrounding air temperature to assess whether your automotive AC system should turn off or on. However, in these situations below, their readings might be inaccurate: 

  • They are installed near windows, exposed directly to the sunlight.
  • They stay close to spaces/sites hotter than other car compartments, receiving restricted airflow.

Such circumstances cause the thermo to produce poor or erroneous readings, giving the impression that the car is colder or hotter than its actual temperature.

We suggest you reposition them in a centralized and more convenient area.

3. Unclean Condenser Coils or Throttle Body

Throttle Body

Ask yourself whether you have conducted any maintenance for your AC in recent years.

No? Then it’s likely that its condenser coil has been filled to the brim with debris and dirt – the direct consequence of little to no cleaning attempts.

These AC coils, positioned in the outside compressor units, are directly responsible for the car’s heat release.

Being blocked by too much filth and dirt will overheat the air conditioning, shutting it down on a frequent basis.

Things hit the same for a dirty air filter/ throttle body, which cuts down the necessary air circulation and results in direct airflow issues, such as short cycling.

Rough idle during the AC operation also occurs. So remember to replace or clean these AC coils and filters whenever possible!

4. Oversized AC

Has this problem plagued your vehicles for years, or did that only spark recently after you have set up a new AC system?

If the latter is the case, your system might be oversized, suffering from a lack of proper refrigerant cycle.

Many difficulties arise as a result, such as excessively rapid cooling processes and sudden shut-off, among others.

Some might argue that quick cooling is more of an advantage than a drawback, but that couldn’t stray further from the truth!

Your car suffers from uneven cool-downs, which is why the air conditioner turns on and off every few seconds.

Most cases are not too serious; still, some unfortunate drivers might encounter concerning consequences, such as: 

  • Power Waste: The central air conditioner turning on or off frequently demands lots of power and electricity.
  • Frequent Repairs: Inconsistent cycling and shutting down leads to more wear and tear, which forces you to furnish it often.
  • Short Lifespan: The wear and tear mentioned above will obviously reduce the typical AC’s life expectancy.

Use a sizing calculator to measure the system’s required size, and discuss with HVAC professionals for a more in-depth inspection of your installation process.

5. Leakage of Refrigerant or Compression Failures

Leakage of Refrigerant

Refrigerant charge is a critical coolant in the engine that circulates throughout your air-conditioning unit, absorbing excessive heat while lowering the air temp.

Leakages will make them drip out, increasing the compressor’s pressure and manifesting random AC shut-off.

As leakages are quite a severe defect, we suggest you turn to a professional service company for further checks and fixes.

Similar to refrigerant leaks, a failing, malfunctioning, or overheated air conditioner compressor might shut down your system repeatedly.

So once you notice your air conditioner’s short-circuiting every two to three minutes, that’s likely the reason!

6. Frozen Evaporators and Electrical Problems

Frozen conditioner coils are another cause you probably should consider. When they freeze up, the air-conditioning unit (or sometimes only the exterior part) shuts off till the ice melts and switches back on.

Your best bet would be to check the exterior section for any ice accumulation.

Operation failures in the electrical components are also a typical reason why your AC compressor runs then shuts off  – caused by unsolved issues in the supply line, electrical connections, thermostat, or circuit board.

The simplest counterattack is to contact a professional electrician in the area.

After all, these problems are quite challenging even for seasoned drivers, and any wrong move may compromise their safety!

7. Bad Running Capacitor and Clogged Drain Lines

Bad Running Capacitor

The AC’s run capacity takes charge of the energy burst necessary for proper turning on and off, supplying continuous power to foster operation.

You could have already guessed the catastrophe that will occur once this component fails! As the power supply becomes inconsistent, the AC compressor starts then shuts off several times.

In another vein, most air-conditioning systems come with a pressure switch for safety purposes, which might shut down the entire system if the drain line’s water does not flow properly and suffers from a lack of adequate backing up.

The underlying cause of this failure might lie in the subpar air circulation in the thermostat, so take a look at it as well.

How Can We Fix These Problems?

Overall, you should leave these problems for trustable and experienced mechanics. However, simple tasks (like cleaning the dirty filter) can still be done at home.

Go To A Repair Shop

Most of these dilemmas are pretty serious; hence, we still think it would be best to bring your vehicle to a trustworthy and experienced mechanic.

They often have special receptacle collections to fix coolant leakages, unclog filters, and so on.

It is true that the market does sell some recharge kits for air conditioning. However, determining how much should be added and how much you currently are adding is quite a challenge.

Wrong calculations might overcharge your system and lead to damage.

DIY Repair

Fortunately, there are still some minor repairs you can perform in your home garage. For instance, you may inspect the compressor motors and wires to observe whether they are properly connected.

A DIY coil cleaning process is also alright. Use a specialized coil cleaner to saturate all the dimes before rinsing them.


This article explains why your AC compressor shuts off after a few second.

This delicate matter would receive the best treatments at a repair shop, but you can still perform quick checks at home or clean the clogged drain lines with a dry cloth!

For more guidance or clarifications on why your air compressor shuts off after a few seconds, write to Bryan’s Garage.

We will try our best to give you adequate advice.

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