What Happens To A Car When The Serpentine Belt Breaks? 2023

Cars are equipped with various peripheral devices which allow their engines to function adequately. These devices include an air conditioning compressor, water pump, power steering pump, alternator, and many more.

Without a serpentine belt, all these devices cannot function properly because this belt drives them all. Although you can still drive some minutes after the serpentine belt breaks, running into such issues at the beginning of the week, or on a long trip is even more frustrating.

Read on to know the details about what happens to a car when the serpentine belt breaks, the symptoms of a failing serpentine belt, and the average cost to replace it if need be.

Symptoms of a Failing Serpentine Belt

What Happens To A Car When The Serpentine Belt Breaks

A failing serpentine belt is not something you can do without in a long while. This is because the full functionality of your vehicle is compromised if your belt is cracked, snapped, worn, or damaged. Therefore, knowing the symptoms of a failing serpentine belt is fundamental to ensuring that your vehicle is kept in good shape on a going concern.

Some of the signs of a failing serpentine belt are:

  • No power steering
  • Squealing sound
  • No air conditioning
  • Visible belt cracks
  • Overheated engine
  • Pulley whine
  • Dead battery

No power steering

Your power steering is inefficient and ineffective without the serpentine belt. It enhances your ability to steer the vehicle smoothly without applying much pressure. A bad serpentine belt makes it very hard to move your steering wheel or drive effortlessly.

power steering fluid

Although this issue also relates to a low power steering fluid, after you have confirmed the recommended level of your power steering fluid, the next checkpoint should be your serpentine belt. Power steering failure can lead to serious safety issues, especially while on the motion.

Squealing sound

A squealing sound from the front of your vehicle is an indication of a slipping, misaligned, or failing serpentine belt. Sometimes, it just takes a realignment or tension to fix it. However, in many cases, unless you are a DIY car owner, you may have to get the help of a professional to replace the entire belt for you.

No air conditioning

Although many other factors can cause a malfunctioning air conditioning system, it does not exclude a failing serpentine belt since this belt is responsible for the functioning of your air conditioner.

serpentine belt

The inability of your air conditioner to blow out cool air might be a sign of a failing serpentine belt. You should take a further step by checking if your serpentine belt is still effective for driving your air conditioner compressor.

Visible belt cracks

In most cars, the serpentine belt is easy to access, so to know a failing belt, you can open the hood and check for yourself. If there are any visible cracks or damage to the belt, it means the belt has failed and must be replaced immediately. Other checks are uneven rib wear, damaged ribs, missing chunks, abrasions, rib separation, and unusual appearances.

Overheated engine

Your water pump is connected to the serpentine belt because the belt drives the pump and makes it release water when it ought to. A worn belt will not drive the water pump needed to cool off the engine and can result in overheating.

To see if your car is overheating, check the temperature gauge and see the direction of the needle. If it is towards the red zone, your vehicle is overheating, and continuous usage could damage your engine.

Pulley whine

An intermittent whine that changes your car speed can become noticeable if you have a failing serpentine belt. Sometimes, this could result from a low-tension belt that you have to check. Also, if the belt is too tight, it puts the excess load on the bearings and, ultimately, the pulleys connected to those bearings.

Once the bearing fails, the water pump also fails. So, you need to ensure your belt is not extremely tight to avoid costlier repairs.

Dead battery

The alternator in your car engine is responsible for charging the car battery. Whenever you are driving and you lose power intermittently, check the serpentine belt to see if it is still attached to your alternator. Even if you can start the car with a jump start, your alternator will not charge your battery in the future.

spark plugs

In addition, the battery is responsible for a host of other things like your radio, headlight, and spark plugs. So, these components will later fail in operation with a bad serpentine belt. Unfortunately, this same symptom can become our experience even with a snapped belt.

Performance Loss

Performance issues become noticeable with your vehicle if its serpentine belt is failing. When you start noticing flickering lights, dimmed headlights, failure to start, and so on, know that your serpentine belt has decided to go on a holiday.

What Does the Serpentine Belt Control?

A serpentine belt is also called an accessory or drive belt because it powers the individual devices external to the car engine. Devices like the compressor, alternator, air conditioner, and other systems are related to the serpentine belt.

Many cars use more than one belt because their manufacturers divide the tasks of controlling all these devices among two to three belts. In addition, the critical function performed by the belts makes them essential to the engine system and calls for a routine inspection.

The devices the serpentine belt controls can be divided into two broad categories: the mechanical and the electrical components.



The serpentine belt powers the mechanical components around your car’s engine. For example, the power steering depends on the power delivered by the belt. Also, the air conditioning system of your vehicle is connected to the serpentine belt. It means your radiator fan, compressor, water pump, and many other components will stop working without a functional serpentine belt.


Your serpentine belt plays a critical role in the overall charging of your car’s electrical system. It is attached to the alternator’s pulley to provide power to this unit. The alternator charges your car’s battery and holds electrical charges needed for a host of other things in your vehicle.

The serpentine belt replaces the traditional ‘V’ belt that the older alternators use, so with just one belt, all other external devices are driven without getting separate belts for each of them.

Important note:

serpentine belt

A serpentine belt can only fulfill its purpose when held under correct tension; it works with a tensioner (a mechanical device) to apply the right amount of resistance or force to the belt and drive all the components simultaneously.

A loose serpentine belt will fail in its functions and become inefficient over time, with a whistling sound accompanying it. Older cars need a manual adjustment, while newer ones already have tensioners that adjust the belt automatically.

What Happens if a Serpentine Belt Breaks?

Now that you know what a serpentine belt controls, let us dive into the details of what happens if this belt breaks while driving or when parked in the garage.

The first thing that happens when your serpentine belt breaks is that all accessories connected to it lose power and will not be able to spin correctly; when your serpentine belt breaks. These accessories include the radiator fan, power brake, water pump, alternator, compressor, air conditioning system, and general cooling system of the car.

This leads to power loss or a decrease in power supply to the electrical system. For example, your steering wheel can immediately become very hard to turn due to power loss, and this is not good, especially if you lack enough strength to drive without one. In addition, it could disrupt your day’s journey.

water pump

Also, your water pump could become ineffective in supplying coolant to the car’s engine, therefore, leading to overheating. In addition, your alternator stops generating power to charge the car’s battery to function other electrical components in the car.

Although your serpentine belt cannot last forever, it could last you some 60 to 90 thousand miles even with proper maintenance. With the advancement in technology, some belt materials can give you up to 100 thousand miles. In any way, you should also confirm these figures from your owner’s manual so that you can get a specific range for your car.

Can Car Run Without Serpentine Belt?

No, your car cannot run without the serpentine belt because the engine will overheat, and a host of other accessories will stop working. In addition, if your serpentine belt breaks all of a sudden, your car may have to be towed because you will not be able to drive it as you often do.

A car was designed so that when one component fails, it only takes some time before others fail too. So, for example, a vehicle without a serpentine belt will only need a little time before its piston gets warped and the engine blocks crack from within.

Of course, it takes time before a tow truck comes by, and then the waiting time before it arrives, but this does not justify you driving without a serpentine belt. You can only continue the journey if your car is one of those built to supply engine coolant without the serpentine belt.


Besides, the average cost of replacing a serpentine belt is affordable compared to driving without it. So now, let us look at the average cost to replace a serpentine belt.

What is the Average Cost to Replace a Serpentine Belt?

Replacing a serpentine belt depends on how you want to go about it. A DIY car owner will only spend $58 on the part but must be ready to face off with the replacement for some hours because the difficulty level is intermediate.

To replace it at the mechanic workshop will cost an additional $54 to $68 on labor, totaling $126. Therefore, unless your belt gets damaged all of a sudden, you should make your serpentine belt replacement as part of your scheduled maintenance.

This will help you anticipate failure and cater to it before it happens. Although most serpentine belt has a 4-year warranty and cover about 100 thousand miles before replacement, you should still check them out during your routine maintenance.

In addition, your car’s serpentine belt might not cover as much distance because the time to replace it also depends on usage. So, to avoid engine damage, it is best to replace it when it is about to clock the 4-year age. Anytime you hear the squealing sound, get right down to know the actual problem.

Which Serpentine Belt Do I Need?

The best serpentine belt should have some of the following key features, and any belt that has these features is the one you need. In addition, you should consider the following in knowing the best serpentine belt for you.

  • Type of rib pattern
  • Shear resistance
  • Material used
  • Durability
  • Belt size

Type of rib pattern

Top serpentine belts

The rib pattern of your serpentine belt is an essential consideration because it contributes to the belt’s lifespan. Top serpentine belts have numerous valleys and crosscuts that allow more air to reach under the belt, therefore preventing stretching and overheating.

Shear Resistance

Shears and cracks are some of the structural failures accompanying a serpentine belt. Therefore, you should go for a belt that resists these structural failures. Although, the shear resistance has a lot to do with the materials and design of the belt, which makes them crack-resistant most times.

Material used

MOCA EPDM Serpentine Belt

Before Ethylene-Propylene-Diene-Monomer (EPDM) was introduced, the former material used to make serpentine belt was Neoprene. However, Neoprene received bad reviews for being shiny and developed cracks in no time. So, you should ensure you have a belt whose material is EPDM.


Any serpentine belt that cannot promise you about 100,000 miles before replacement is not strong enough to withstand rough conditions and heat. The average lifespan of a serpentine belt is about 60,000 miles. So, any brand with reviews less than 60,000 miles is a no-go brand for you.


The model number on the worn serpentine belt is essential for its replacement. If the old belt is too worn to see the model clearly, you can measure it yourself after taking it out. After measurement, you should pick the belt that is one size smaller.

This will help you get the best fit. Also, your car owner’s manual should have this detail (if you still have it) so that you can get the proper size that fits your car.

Here is our list of the best serpentine belt in the market today; all these belts meet these specifications, and the only thing left for you to do is to ensure it’s the size that fits your car.


How Long Can a Car Engine Run with A Broken Serpentine Belt?

Although this depends on the car and other associated factors, your vehicle can only run for an additional 20 to 90 minutes before it packs up. So if it’s a hot day, your car engine will overheat, and in modern cars, the engine light comes on to indicate overheating. On the other hand, on a cool day, you can buy yourself an additional 90 minutes to get down to the mechanic workshop.

Can A Car Start with A Broken Serpentine Belt?

Yes, your car will start with a  broken, bad, or missing serpentine belt, but you should be more concerned about what comes next. The battery powers the starter to keep your car going so that combustion can begin and power generated can move your vehicle. However, it is only a matter of time before your battery runs down, and that won’t be good if you have a long trip ahead.

Wrapping Up

Having understood the critical functions performed by your serpentine belt, you should take cognizance of the signs and symptoms of a failing serpentine belt so that you can work on it before complete failure.

Also, you save more money (especially as a DIY car owner) by making it scheduled maintenance rather than drive, assuming all is well with your car.

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