3 Steps How To Fix a Shredder That Won’t Turn Off

October of last year, the results of my midterms came in. I had performed poorly would be an understatement. Envisioning my parents being disappointed, and to save them from this misery, I decided to give the new paper shredder a test run.

To fix a shredder that won’t turn off, wipe away any dust or debris covering the sensors. Locating the sensors on your shredder can take effort, but once you do that and the sensor is clean, the shredder will be set in most cases.

In the remainder of this article, I will cover questions related to this scenario. This includes why your paper shredder keeps running after usage, the types of sensors, locating the sensor, how to clean a shredder sensor, and how to prevent damage to a sensor.

Why Does Your Paper Shredder Keep Running?

You’re having a problem with your shredder; the machine is behaving in a haunted manner and won’t stop after devouring your precious paper. It is only human to worry and consider sending it back to the manufacturer.

A shredder that keeps running has sensor-related issues. This usually does not indicate mechanical or electronic problems. In most instances, it requires little maintenance, and the problem is soon solved.

A continuously-running shredder mainly exhibits an issue related to the shredder’s sensor. It is exacerbated by debris, which may block the sensor.

This YouTube video does well in explaining how to fix a paper shredder that won’t stop:

Read: How Long Can You Run A Paper Shredder?

Types of Shredder Sensors

First, you need to know your shredder machine’s different types of sensors. They include:

• The auto-start/stop sensor 
• A bin/bag sensor 
• An overload sensor
• A load indicator sensor

A few practical measures can protect your machine from damage and you from accidents.

A shredder that won’t turn off has an auto-start/off sensor issue. The auto-start/off sensor comes in two modes: a photo sensor and a mechanical type. Identifying the type of sensor will help you locate and fix it.

Mechanical Sensor

This type of sensor consists of a metallic part that is depressed once a paper is fit into the tray. This signals the machine to start shredding. Once the document’s weight disappears from the tray, the sensor returns to its position and the shredder stops.

This type of sensor is disadvantaged as its sensitivity reduces over time and is the main reason for the dysfunction in these types of shredders.

Read: Jammed Paper Shredder Won’t Feed Paper. How To Fix It?

Photo Sensor

This sensor is more reliable than the mechanical subtype as it covers almost the entire tray. It consists of a detector and a light source easily identifiable by a color marking. A photo sensor malfunctions mainly due to damage caused by dust.

Photo sensors have a protective mechanism and should never be disabled to prevent exposure to dangerous accidents and consequences.

Where Is the Sensor Located?

Identifying and locating the sensor is the first step in troubleshooting your shredder. Most shredders, including models from Fellowes, MBM, GBC, Martin Yale, HSM, and Dahle, have sensors placed near various parts. After turning off the machine, you can use a flashlight to locate the sensor.

The sensor location is identified using the user manual. The mechanical type of sensor is located at the top of the shredder. In contrast, the photosensor can be found in the center of the paper entry throat.

Suppose your model has safety flaps over its cutters, in that case, you will have to remove them before the sensor can be located safely.

Read: How To Fix A Paper Shredder That Won’t Turn On?

How To Clean a Shredder Sensor?

Once the sensor has been successfully located using a flashlight, it can be cleaned using a variety of objects.

This YouTube video will give you a fundamental understanding of how to clean your shredder sensor:

A cotton swab, straw, or soft fiber cloth can easily clean the sensor. However, the exact method to clean it will be different for both the photo and mechanical sensor.

How to Clean a Photo Sensor?

To clean a photo sensor do the following: 

1. Unplug and remove your device from the power source. 
2. Locate the sensor. 
3. Dip the cotton swab or the soft fiber cloth in isopropyl alcohol or propanol (it should be damp, not dripping). 
4. Clean all sensor parts carefully, removing the dust, oil, and debris, without damaging any sensor part.

However, accessing the sensor in some shredding machines might be challenging. After unplugging and removing the appliance from the source, you should take the paper catch bin out and turn the shredder upside down. Then, use a screwdriver to unscrew the machine, flip the unit with the right side facing up and the top piece held firmly. 

One side of the top piece will be looser than the other end thus you can carefully remove it without damaging any parts.The shredder sensor should not be easily visible.

The above procedure will fix the problem in most cases, and your shredder should be back up and running.

If it doesn’t work, the sensor has a technical issue, and you need to contact the manufacturer.

Read: Why Do Paper Shredders Overheat? – Troubleshooting Guide

How to Clean a Mechanical Sensor?

Unfortunately, a mechanical sensor doesn’t have as simple a fix as cleaning it with a piece of cotton. This is because, in most cases, the issue lies in the sensitivity of the tray that signals the machine to start/stop shredding.

A mechanical sensor that won’t stop after shredding might have dust, food, or a definite article forcing down the tray. Paper parts are commonly found forcing down the sensor in this type of shredder. You need to carefully examine the paper tray in your device, and if stuck, disassemble and then reassemble it.

You can also try inserting a pointed object (a toothpick or needle) into the sensor’s hole to see if there is any difference in the machine’s behavior.

Finally, if all else fails, replace the part.

Prevention of Sensor Malfunction

Sensors are subject to wear and tear like all electrical and mechanical equipment.

The most common cause of your shredder not stopping is if the sensor becomes cloudy due to dust or excessive light exposure over time.

Thankfully, all the issues mentioned in this article can be prevented by doing the following:

• Clean the auto-start/off sensor and related parts thoroughly in case of a photo sensor.
• A mechanical sensor is rarely fixed by simply cleaning it. However, it can be repaired or replaced.
• Clean the paper detection sensors.
• Ensure that the shredder is not placed directly under excessive sunlight; this can easily damage the sensors.
• Make sure to maintain your shredder thoroughly and regularly.
• Use soft cloths, vacuum, and cotton swabs dampened with alcohol for cleaning.
• The shredder blades work by cutting the paper. The dust eventually builds up, which wears them down. Thus you should regularly oil the blades as instructed in the manual.
• In case of any issues, place a service call or contact your manufacturer’s customer support.

A shredder can bring up a lot of problems, the sensor being one of them. In this case, it is necessary to consult the user guide provided with your machine for optimum performance. All companies also offer helplines for customer support and satisfaction.

Document Dynamix has also provided an online guide to troubleshooting problems related to your shredder machine.

Read: Why HP Printer Not Communicating With Computer?

Final Thoughts

A paper shredder, an essential office appliance also found in homes, is used to eliminate useless paper. Like all machines, it is susceptible to faults and problems.

It’s vital to maintain and take care of your shredder. Hopefully, the methods mentioned here will solve your problem of a continuous running shredder in most cases, if not all.

However, you may need to consult a professional if your issue persists.

So, next time you decide to get rid of classified papers or academic results that your parents shouldn’t see, consider hiding them instead of feeding them to a malfunctioning shredder!