Cooling Performance of The Hybrid Battery is Low

Hybrid car batteries are popular among eco-conscious drivers due to their lower emissions, but they aren’t immune to problems. So you may notice the cooling performance of the hybrid battery is low if something is wrong with the cooling system.

Your car can show this error message due to a clogged cooling fan, jammed radiator, blocked bearing or faulty battery. However, you can clean the cooling fan or reset the battery to remove this warning light. If these don’t work, you’ll have to pay thousands to repair or replace the battery to fix the issue. Let’s get the details

What is Cooling Performance of the Hybrid Battery?

The cooling fan of the hybrid battery circulates air from the cabin through the battery modules to keep the battery cool.

When the car shows this error message, the cooling fan performance isn’t sufficient or the cooking system isn’t working properly. Owners of Lexus IS300H and Toyota Prius are familiar with this issue.

It can happen due to insufficient airflow around the battery. If something blocks the airflow, there will be inadequate airflow around the battery.

The hybrid battery may also become overheated due to the heat coming from the engine and other components. Hence it can turn on the “cooling performance of the hybrid battery is low” light on the dashboard.

HV systems usually have a 5 to 8 years warranty. So if your HV system is still under warranty, take it to the dealer and fix the problem. You can also inspect the cooling vent that is placed in the rear passenger seat’s corner and next to the door.

Make sure any obstruct don’t block the airflow which can result in the error message. You may need to disassemble the cargo area cover to get access to the HV battery. Otherwise, you can take the aid of Advance Auto or Auto Zone store to solve the problem.

Reasons and Solutions of Cooling Performance of the Hybrid Battery is Low

Below are some potential reasons that result of cooling performance of the hybrid battery is low light on your car’s dashboard:

1. Clogged Radiator

Coolant flow through the radiator and cool the hybrid battery. If the radiator is jammed or leaked, the coolant won’t flow properly. As a result, the battery won’t become cool adequately.

Clogged Radiator

A clogged radiator may also make the battery overheat and damage other components of the vehicle. To determine if the radiator is jammed, check the coolant level. If the level is low, the radiator may become faulty.

2. Jammed Cooling Fan

The cooling fan remains closed or even attached to the battery. The most common reason that causes the cooling fan’s low performance is the pet’s hair on the back seat. The cooling fans perform like a vacuum cleaner in the intake vent area. Sand or dirt can also clog the cooling fan.

Jammed Cooling Fan

To solve this problem, remove and clean the fan and make sure it spins freely. You may need to replace the cooling fan if it doesn’t perform optimally.

3. Blocked Bearing

There is a bearing on the back of the cooling fan that may become locked due to dirt or dust. If so, lubricating the bearing can help disappear the error message on the dashboard. To do this, disassemble the fan and remove the round aluminum disc found inside the fan.

There is also a paper sticker in the middle of the disc. Remove the disc to get access to the bearing and use light oil to lubricate it. Then replace the sticker with a fresh piece of tape to prevent dirt from entering inside.

4. Extreme Ambient Temperatures

Liquid coolant keeps the hybrid battery at the right temperature. If the temperature drops or rises, the cooling system works hard to maintain the optimal temperature for efficient operation. The battery cell can shrink at low temperatures and tend to get damaged due to vibration. Conversely, the cells expand at high temperatures and can cause short-circuit or leakage.

In either case, the car can activate the cooling performance of the hybrid battery is low light on the dashboard. To avoid the problem, use a battery thermal management system as it helps reduce the battery’s heat generation and maintain the perfect temperature.

5. Aging

The hybrid battery’s performance can be deteriorated due to aging. As time goes on, the battery’s ability to dissipate heat may also decline. It can force the vehicle to show the error message. If the battery is almost expired, replace it to restore the performance and disappear the error message.

6. Battery Problem

The battery’s faulty connection may also prevent it from cooling down properly. If you use the battery for an extended period, its capacity may decrease. Hence the cooling performance of the battery can become low which results in a warning message.

hybrid Battery Problem

The battery cell also fails due to using it for a long time and starts making an imbalance in the pack as well as overheating the battery. In this case, you have to replace the battery.

How to Clean Cooling Fan to Disappear this Warning Light?

A hybrid battery is one of the costliest parts of a car. If it shows the error message, the battery may be about to fail. As soon as you notice the massage, inspect the car by yourself or hire an expert mechanic. Before taking the car to an auto repair shop, you can give yourself a chance to clean the fan to see if the message disappears. Below is the procedure:

Though the placements of a cooling fan vary from model to model, you should find it in the boot, on the right side over the wheel arch. Firstly, disconnect the battery so the current can’t flow through the circuits. Don’t remove the air fan from its wire. Just plug out the plastic pins and bolts that hold the fan onto the structure. This way you’ll get access to the fan without removing it completely.

Use a soft paintbrush to remove dirt from the fan and outside of the fan radius. Cover other intakes from the flat black plastic tubes that run under the cover through the battery to keep them clean during cleaning the fan. Clean the air intake that is placed on the right side of the rear seat. After plugging the battery and running the fan, the warning message should disappear.

How to Reset Low Cooling Performance of the Hybrid Battery?

Your car may show the cooling performance of the hybrid battery is low light due to a simple malfunction that you can easily solve by resetting the battery. Below is the process of resetting a Prius 12v Battery and restoring its cooling fan’s performance:

Reset Cooling Performance of the Hybrid Battery is Low Problem
  • Turn off the car and remove the ignition key.
  • Find out the hybrid battery which is usually placed in the trunk.
  • Disconnect the negative terminal of the battery by loosening its bolts using pliers or a wrench.
  • Connect the negative terminal to the positive terminal of the battery. It’ll create a spark and reset your hybrid battery.
  • Then reattach the negative terminal to its original place and secure it with bolts.
  • Turn on the car and run it for a while so the battery can start recharging. At a time, you should notice that the cooling performance of the hybrid battery in low light has vanished.

Cost of Fixing the Cooling Performance of the Hybrid Battery

The hybrid battery comes in different types including mild hybrid, plug-in hybrid, and full hybrid. Different makes and models use different types of hybrid batteries.

Hence the cost of fixing this warning light problem varies depending on the make and model of the vehicle, the type of hybrid battery, and the source of the problem. According to AutoZone, if you need to replace the battery pack to disappear the error message, it can cost around $1,000 to $6,000. However, the most common hybrid battery cost under $3,000.  

Installing a high-voltage hybrid battery may take a few hours or even a full day. So you have to pay around $500 to $1,500 to a certified mechanic. But if you only need to replace the hybrid inverter coolant drain, flush, and refill, it’ll cost only around $170 to $194. The labor cost will be around $90 to $113.


Does AC affect the cooling performance of the hybrid battery?

The AC runs off the hybrid battery. So the charging system of the battery can go down quickly which can make the cooling fan weak and disturb its cooling performance.

How to improve the cooling performance of the hybrid battery?

To improve the cooling performance, keep the cooling fan clean of any dust or obstacles. Drain the battery regularly and recharge it to full capacity as well as make sure all its connections are secure and working properly.

Do Hybrid Cars Have Multiple Cooling Systems?

Yes, a hybrid vehicle has a minimum of two cooling systems. One for the vehicle’s gas-powered or diesel engine and the other one is for the electric engine.

Final Words

If you notice the cooling performance of the hybrid battery is low, don’t get panic. Instead, clean the cooling fan and make sure all the connections are secure. If you have pets, don’t let them seat near the cooling fan.

If any of those ideas don’t work, bring the car to a licensed mechanic. Remember, a little awareness and routine maintenance can help you keep this warning light off and avoid expensive repair costs. 

My name is Henry Roberts and I am an experienced car mechanic with over 15 years of expertise in the automotive industry. I am currently running a Auto Repair Shop in Denver, Colorado. I have been servicing and repairing vehicles at my shop, where i have built a solid reputation for my skill and knowledge. I am passionate about sharing my automotive knowledge through blogging and my goal is to provide accurate and helpful information to car owners to keep their vehicles in perfect condition.

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