Car AC Pulling Too Much Power – reasons and fixes – 2023

If you’ve observed that your car’s AC system is using too much electricity, it’s essential to investigate the root causes and take action before they develop into more significant problems. 

Inspect the belt for cracks or glazing. Replace if over 5 years old. Slipping due to wear strains the engine while compensating for the AC load.

In this article, we will explore why a car AC system pulls too much power and provide insights into how to diagnose and rectify the problem.

Why Does Car AC Pulling Too Much Power? Best Ways To Fix It:

1. Condition of the Belt: Is It Time For A Replacement?

The performance of an automobile’s air conditioning system is greatly influenced by the state of the belt that powers the compressor. These belts may deteriorate with time, creating issues like slippage. Wear can be seen as surface cracks or glazing on the belt.

Condition of the Belt

A belt slipping due to wear forces the engine to overcompensate for the AC load, or the load imposed by the compressor will be excessive. This engine overuse results in higher power consumption and AC system inefficiencies.

How To Fix:
Regular maintenance is essential. Check the belt’s surface regularly for glazing or cracks. Replace the belt when it shows wear or is older than five years. A fresh belt guarantees optimal grip and minimizes sliding, lessening engine stress.

In turn, this reduces excessive energy use and improves the effectiveness of the AC system. Consult a qualified mechanic for a complete evaluation and replacement, if required.

2. AC Problems: Compressor Wear And Engine Health:

The AC compressor and the condition of the engine as a whole are frequently to blame for an automobile’s air conditioning system using too much power. An AC problem (worn-out compressor) or simply a well-worn engine are the reasons for power pulling.

AC Problems
source:oards automotive

A damaged AC compressor places an additional demand on the engine’s power, requiring it to work harder and consume more gasoline. On the other hand, a worn-out engine might be unable to supply the necessary strength, adding extra strain to the AC compressor. These connected problems may load the overall system, increasing power usage.

How To Fix:
Quick action is essential. Consult a qualified technician to do complete engine and AC compressor diagnostics. Consider replacing the compressor if it shows signs of wear to reduce the engine’s need for extra power.

The engine’s power output can be increased by handling any underlying issues and performing maintenance. Addressing issues with the compressor and engine improves overall effectiveness and reduces power usage. Regular servicing and monitoring are crucial to avoiding such problems and maintaining optimal performance. 

3. Slipping Belt: Compressor Load And Engine Strain:

A slipping belt is a clear sign of excessive power consumption in a car’s AC system and serves as a warning sign. The AC compressor’s increased demand on the engine is the primary culprit. The belt’s grip deteriorates as demand rises, which can cause sliding and eventually fracture.

Slipping Belt
source:tomorrows technicians

There is potential for severe damage due to the consequences, which go beyond AC disruption. Further problems could result if this problem is ignored. 

How To Fix:
Whenever you notice a slipping belt, call a qualified mechanic right away. They will carefully examine the stress placed on the engine by the AC compressor and evaluate the belt’s condition. Resolve the fundamental problem by adjusting the compressor’s demand and ensuring the belt is tensioned correctly.

Address any associated problems that can make the issue worse simultaneously. The most crucial aspect of maintenance is routine monitoring of the belt’s performance and rapid correction of any anomalies.

4. Dirty Or Blocked Condenser And Refrigerant Charge: Hidden Culprits Of Power Drain:

Two hidden culprits within the car’s AC system can be found in the shadows of high power consumption: a dirty or obstructed condenser and insufficient refrigerant levels. A clogged condenser forces the AC compressor to work harder to remove heat, which increases amp draw and power consumption.

 Dirty Or Blocked Condenser And Refrigerant Charge
source:car from japan

Similarly, low refrigerant levels prolong compressor uptime, increasing power usage. Together, these covert factors contribute to the AC system’s power loss.

How To Fix:
Regularly check and clean the condenser to ensure free airflow.  It lessens the load on the compressor and cuts down on energy use.

Regular inspections and adjustments of the refrigerant level keep it at the ideal level, reducing the need for prolonged compressor operation. Clean the condenser thoroughly or get professional assistance if it’s clogged or unclean.

The same goes for problems involving refrigerant; seek the advice of a specialist and top off as necessary. Taking care of these covert offenders protects your vehicle’s power effectiveness, enabling a harmonious balance between cooling performance and minimal power demand, assuring both comfort and cost-effective operation.

Identifying Excessive Power Consumption In Your Car AC System: Common Symptoms:

1. Tripping Circuit Breaker:

Circuit breaker tripping is one of the most obvious signs that your car’s AC system uses too much power. If the breaker for the air conditioning system in your car frequently trips, there may be a problem.

Tripping Circuit Breaker

This incident shows that the AC system is using excessive power due to underlying system problems. Ignoring this indication can eventually result in more situations and expensive fixes.

2. Dimming Lights And Electrical System Issues:

The car’s electrical system may become overworked if the AC system uses less power, which could cause lights to fade or even flicker. The AC system’s power consumption impacts your car’s electrical stability if you notice that your headlights or interior lights fade when the AC is on.

Prompt resolution of this problem can retain the functionality of the AC system and other crucial auto systems while reducing further stress on the electrical components.

3. Engine Strain And Reduced Performance:

An excessively power-pulling AC system might place a heavy burden on the engine. This strain may result in sluggish acceleration, poor fuel efficiency, and decreased engine performance. Suppose your car’s engine is suffering when the AC is on.

Engine Strain And Reduced Performance
source:motor verso

It indicates that the AC system’s power usage negatively impacts the engine’s capacity to perform at its best. Your car’s performance and general driving experience can be improved by locating and addressing the underlying problems.

4. Unusual Noises From The Compressor Or Engine Area:

You can hear noises coming from the compressor or engine area when the AC system in your automobile is working too hard. These noises could indicate that the engine is having trouble supplying the extra power requirements or that the compressor is working harder than usual.

Noises like grinding, screaming, or rattling frequently indicate these problems. By promptly diagnosing and maintaining these noises, it is possible to prevent further harm to vital components.

5. Reduced Cooling Performance:

An AC unit that consumes less power can have trouble cooling the room effectively. You might see that the system takes longer to achieve the correct temperature or that the air from the vents is more chilly than it used to be.

 Reduced Cooling Performance
source:PA auto inspection

The decreased cooling capacity may be caused by the AC system using energy inefficiently, which highlights the necessity for a complete evaluation and needed repairs.

How To Reduce AC Load on the Engine?

  • Set the air conditioning to a temperature that is pleasant but not freezing. Finding a balance helps you save energy because lowering the temperature setting requires more power from the engine.
  • Change to the fresh air mode rather than the recirculating cabin air while driving in fair weather. It lessens the demand for constant cooling and eases the burden on the air conditioning system.
  • Open the windows to let fresh air into the car before you leave. Once you start driving, turn on the air conditioning. This tactic lessens the system’s initial load.
  • Select shady parking spaces to reduce interior heat buildup. It lessens the cooling load when you first start your car.
  • Start with the thermostat set to a warmer setting and the fan on high. Reduce the fan’s speed and the temperature setting as the interior cools.
  • Use the AC sparingly, particularly on highways where the aerodynamic drag from open windows can outweigh the system’s advantages.


1. Why Is My Car AC Compressor Building Too Much Pressure?

You will feel intense pressure, even with the engine off. The air conditioning system has either an excess of oil or refrigerant. In either instance, the problem will only go away once you release part of that pressure, which a mechanic should do.

2. What Happens If You Pull Too Many Amps?

Electricity drawn into a circuit at a high rate can cause harm and be dangerous. Insulation can melt when the wiring gets too hot, starting a fire. A more contemporary, reusable alternative to a fuse is a circuit breaker.

3. Why Does My Engine Surge When The AC Is On?

The car’s computer automatically modifies the idle to account for the AC system’s stress on the engine. However, surging can be brought on by carbon accumulation due to overcharging in any system component, including the EGR valve, throttle body, and idle air control valve.


Maintaining a car’s air conditioning system is essential for both your comfort in hot weather and the automobile’s overall performance. When the air conditioning system in your automobile begins consuming excessive amounts of power, problems obviously need to be fixed. A proactive approach to maintenance and troubleshooting may keep your car’s AC system functioning effectively and your engine power usage under control. It includes assessing the condition of the belt, checking the amount of refrigerant, and diagnosing compressor issues. 

Video Guide:

Also Read:

Similar Posts