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You did your due diligence and researched all the best treadmills. You found one that you love, and it’s the perfect addition to your home gym. You use it religiously and look forward to your daily workouts. 

But, one day, a dreaded error code shows up on your display, or your new treadmill simply will not power on. Now what? 

Not to worry; learning how to fix a treadmill may be easier than you think.

Like most home gym equipment, treadmills may have the occasional malfunction that requires some quick action. Regardless of size, brand or cost, most treadmills share common problems that can be repaired without causing serious downtime. Most issues concern the treadmill belt, console display, treadmill motor, or speed performance. This guide will provide you with the key tips and tricks for your treadmill repair. 

Common Problems

Despite the great variety of treadmills on today’s market, they all tend to share the same malfunctions. Whether you’re sweating it out on a NordicTrack, ProForm, Horizon, or using a compact treadmill versus traditional treadmill, you’ll come across some common problems. 

So, who are the usual suspects?

The main problems with treadmills are erratic speed, a slipping belt, non-working console display, a burning smell, and a faulty motor.

Erratic Speed

If you find your treadmill’s speed to be erratic, the problem could stem from a few areas. A damaged or rundown walking belt, lack of lubrication, inappropriate belt tension, or a bad drive motor could all be the source of inconsistent speeds. 

First, check your walking belt to see if there are any obvious flaws that would require you to replace the belt. If the belt seems to be in good shape, check the belt tension and lubrication to ensure the belt slides easily over the deck. If all these things check out, then the problem likely lies with a weak drive motor.

Slipping Belt

A belt that slips is probably one of the most common problems on a treadmill, and likely one that every treadmill owner will experience. Whether you’re using a treadmill for walking or hopping on for a run, slipping can occur when the treadmill belt does not have the appropriate tension. A lack of lubrication also causes the walking belt to stick or slip so it’s important to know when your machine needs some lubrication. Additionally, slipping can result from a poor grip on the front roller. 

common treadmill issues

Non-working Display

Even the most tech-savvy and interactive displays can lead to a headache if they stop working. A non-working display is a common treadmill problem and easily fixed by resetting the power or changing batteries. However, there are some treadmill display issues that may arise and can be a bit more complex to resolve, meaning you’ll probably need to call in the professionals. 

Burning Smell

A burning smell is something that requires immediate attention. It’s important to unplug your treadmill right away if you detect this smell. The source of this smell is usually one of three things: 

  • Improper friction between the belt and the deck
  • Electrical shorts
  • Overheating of the motor 

Regular lubrication and taking time to clean around the motor and fan blades both can help to prevent this problem. 

Controls on the Horizon 7.4 AT studio treadmill

Error Codes

Every treadmill carries its own specific error codes unique to the brand and/or model. That said, many treadmills share similarities in the codes they use. Here is a list of the codes you may encounter when you’re wondering how to fix your treadmill:

  • E01 error code: This usually means that the console board or display is not communicating with the motor control board. This can result from a faulty data cable (which can be replaced) or poor belt lubrication.
  • E02 error code: This code generally refers to a malfunction of either the console display or motor. If the motor is running smoothly, the display likely needs to be replaced.
  • E03 error code: An E03 code most commonly means the motor is not appropriately responding to an increase in speed, which is often caused by a drag in the motor belt. Most drag issues arise from a belt being too tight or too worn.
  • E04 error code: This error code means a power surge has interrupted the motor functioning or it indicates that the motor is disconnected. Simply check to ensure your motor cables are securely fastened and not loose. If so, unplug your treadmill, unplug all cables, and then refasten them prior to powering back on.
  • E05 error code: Usually an E05 error means the console is not communicating with the speed sensor. Locate your speed sensor and ensure it’s clean to potentially remedy this problem.
  • E06 and E07 error codes: These refer to a problem with the incline often caused by damage to the wire connecting it to the lift motor. Or, the lift motor incline range may need to be readjusted. 
  • E08 error code: Depending on the brand of treadmill, the E08 error may also mean there’s a problem with the lift motor control (incline).

It’s important to remember that error codes can vary between brands. While the codes listed here are a great guide, you should refer to the owner’s manual for your specific treadmill. 

Motor Not Working

A faulty motor can be one of the more expensive treadmill repairs you’ll come across, and it can take on many forms. A treadmill that powers on but does not respond to speed or incline adjustments likely has something wrong with the treadmill motor. Treadmills that power up and immediately go at full speed usually have faulty wiring or circuits leading to an issue with the motor. And finally, if your treadmill shuts down mid-workout, the motor may be to blame. 

Unfortunately, fixing a treadmill motor is not an easy repair. This usually requires a professional, given the intricacies of treadmill motors. And that doesn’t come cheap. You can expect to pay at least $200 to $300 for a motor plus the cost of labor. All in, you are likely spending an easy $500, which can be a big pill to swallow. 

Regular maintenance is so important and can prevent many of these problems. There should be suggestions for regular maintenance in your owner’s manual.

Malfunctioning Belt

Treadmill belt slipping and/or belt sticking is an annoying but somewhat inevitable issue every treadmill owner faces at some point. If you feel some hesitation during a treadmill workout, it’s time to investigate. 

A belt that slips and moves at a different angle than the person using it can lead to a dangerous fall. Falling outside when running is one thing, but falling on a moving treadmill is an entirely different animal. Trust me. So it’s important to get to the bottom of this problem right away.

The walking belt works by smoothly sliding over the deck and rollers. When there’s unnecessary friction between these surfaces, a belt will slip or stick. Properly lubricating the belt will fix this problem. Be sure to get a lubricant that’s safe to use on your specific belt (check that owner’s manual).

A belt that’s too loose will also slip out of alignment. You can check this by gently pulling up on the belt. A good rule of thumb is that you shouldn’t be able to get more than three fingers between the belt and the deck. If that gap is larger, it’s time to tighten the belt.  

RELATED: How to move a treadmill

Treadmill deck for Sunny Health and Fitness Treadmill

The drive belt is completely different from the walking belt and can be the cause of slipping. This belt connects the treadmill motor and first roller under the deck, which transfers the motor’s power to the deck. If the drive belt is misaligned, you will feel that same hesitation of the walking belt. Treat the drive belt with an approved belt dressing to prevent any further issues. 

Another source of slipping happens when the pulley, located under the front hood, loses its grip on the running belt. In simpler terms, this means the belt is literally slipping off the front roller or very misaligned. 

Not to worry—there’s a little tape trick that can diagnose this problem. Stick a piece of colored tape from the pulley to the roller in a straight line. Power up the treadmill, and when the belt slips, switch it off and check the tape. If the tape has broken apart, your roller and pulley are misaligned and just need some tweaking. 

No Console Display 

You’re all laced up and pumped to run on your treadmill. But, you jump on, and a blank console display stares back at you. While super annoying, this usually has a simple solution. First determine the power source for your display. If your console display works off batteries, try replacing them. 

If not, check the power cord and make sure it’s securely plugged into the wall and not crimped. In fact, make sure all wires aren’t crimped up and the cable connections are tight. If all looks good, simply unplug your treadmill for 60 seconds and then plug it back in. You may also want to check your circuit breakers, as a tripped circuit breaker can also lead to a blank treadmill display.

Troubleshooting Tips

While we aren’t treadmill doctors, we can offer a few possible solutions if you need ideas about how to fix your treadmill.

How to fix a treadmill troubleshooting tips

Adjust the Belt

While there are many different options out there for your home treadmill, the belts are usually very similar. Whether you’re using a manual treadmill or traditional treadmill, the treadmill belt is usually made from rubber and comes in one of three different thicknesses: single-ply, two-ply and four-ply. The steps to adjust the belt on both treadmills are the same and depend on whether you have a two-adjustment bolt style or one-adjustment bolt. 

But, before doing anything, power off your treadmill.

To know which style you have, you need to inspect the right side of the rear roller. If the bolt there has an Allen wrench head, you have a two-adjustment bolt style. To adjust a two-adjustment bolt style, use the Allen wrench to turn both the rear roller bolts clockwise one quarter of a turn and check the walking belt. If it still needs to be tightened, turn it again. 

Conversely, if you need to loosen your belt, use the Allen wrench to turn both rear roller bolts counter-clockwise a quarter of an inch and check the tension on the belt. 

One-adjustment bolt styles are adjusted by turning only the right rear tension bolt and holding the tension nut on the end of the bolt while putting a second wrench on the bolt head. Again, turn the wrench in small increments to either tighten (clockwise) or loosen (counter-clockwise) your walking belt until the tension is right. 

Lubricate the Belt

Lubricating your belt should be part of regular treadmill maintenance. Many manufacturers have lubricants specifically designed for their line of treadmills. It’s a good idea to purchase some directly from the manufacturer if you don’t receive lubricant with your treadmill purchase. Check your owner’s manual for explicit guidance on appropriate lubricants that can be used. 

All treadmills require a 100% silicone lube, which comes in two forms: silicone spray or silicone liquid. Both are applied the same way, as silicone liquid should be transferred into a spray bottle. To treat your treadmill, use a spray bottle (if using liquid silicone), paper towels, a towel and a screwdriver. 

If possible, place your treadmill on a towel or put some rags around and under it to catch any lube that may drip. Then expose the lower portion of the treadmill belt, loosening the rollers with a screwdriver and lifting the edges of the belt. Next spray the lubricant on the deck in a uniform fashion using the paper towels to wipe off any excess lube. Apply a thin layer on the entire running belt as well to ensure there’s proper and uniform lubrication. Screw everything back in place, and you’re ready to go. 

Word to the wise: Never use WD-40, Vaseline or petroleum-based lubricants on your treadmill.

Check the Power

Now, you may be thinking, “Who wouldn’t check the power?” when their treadmill won’t turn on. But, you’d be surprised. Suffice it to say, it happens. A broken power cord, tripped circuit breaker, faulty power switch, or wiring failure can all prevent a treadmill from powering up.

The first thing to check is the power cord to ensure it’s not crimped and is securely fastened to the outlet in the wall. Next, check your circuit breakers to see if they’ve been tripped and need to be reset. You also want to look at the power switch on the base of your treadmill and all wiring to make sure they’re secured. Generally, checking and correcting these things will get your treadmill back in working order. 

Final Verdict 

As the owner of any piece of fitness equipment, you should provide regular maintenance to prevent any unnecessary problems. But, the truth is that even with regular care and maintenance, most treadmills will eventually run into one of the common issues described here. Understanding how to fix a treadmill and troubleshoot issues that arise will help save you money and time with some easy DIY fixes. 

FAQ About How to Fix a Treadmill

Is it worth fixing my broken treadmill?

Generally, fixing a treadmill is much more affordable than purchasing another. Depending on the part or parts that either need to be fixed or replaced, the cost of a treadmill repair is minimal compared to the cost of buying a new one. That said, there are treadmills on the market that you can buy for $500 to $600. If your treadmill is over 10 years old and the cost to repair is greater than $400, you may want to consider one in this price range.

RELATED: Treadmill Buying Guide

Why would my treadmill motor not be working?

Surprisingly, problems with a treadmill motor usually stem from issues elsewhere. And, not to sound like a broken record, regular maintenance and lubrication can prevent many problems that cause a motor to burn out and stop working.

Most commonly, motors break down when there is too much friction between the belt and deck. On cheaper models of treadmills, the motor consists of cardboard. This immense friction will cause the belt to actually feel hot and in turn, burn through the cardboard and core of the motor. 

Some motor problems are outside of our control. Faulty wiring, motor control failures or electrical surges all can cause a motor to stop working. Follow the troubleshooting tips in this article to diagnose the source.

How long do treadmills last?

Most manufacturers report that a treadmill’s lifespan ranges from seven to 12 years. These numbers are largely dependent on the quality of the treadmill, the frequency of use and equipment maintenance provided. 

How do I get new parts for my treadmill?

Getting new parts for a treadmill can be as simple as a google search. But, before looking to purchase a part, check your treadmill’s warranty. Some warranties will cover issues with treadmill parts so you can get the part you need directly from the manufacturer. If the warranty has passed or doesn’t cover the part you need, hop on the internet and do some searching to find and price out the part. Most parts can be found on Amazon or the manufacturer’s website.

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You did your due diligence and researched all the best treadmills. You found one that you love, and it’s the perfect addition to your home gym. You use it religiously and look forward to your daily workouts. But, one day, a dreaded error code shows up on your display, or your new treadmill simply will not power on. Now what? Not to worry; learning how to fix a treadmill may be easier than you think.  » Read more about: Help Is Here: How to Fix a Treadmill  » Read more