If your dryer cuts out after a few minutes, chances are it is overheating in some way, shape or form. It could mean the vent is clogged, the element is heating all the time or the motor is bad. The moisture sensor can also cause this although this is very uncommon.
Some dryers will cut out in the event that it overheats and if you wait a few minutes, it will cool and allow you to turn it back on. However, if you do not repair the issue it will continue to overheat and cut off. A clogged vent will cause this, so anytime you have a dryer that will run for a few minutes then cut off, the first thing you should check is the vent.
A grounded element will cause a dryer to overheat. As stated above, some dryers will cut off if they overheat so if your dryer cuts out after a few minutes, the element could be grounded out. A grounded element can cause the heating element to put out heat the whole time the motor is running. This will cause the dryer to overheat and when this happens the hi-limit will blow or the dryer will cut itself off due to overheating.
To check this, unplug the dryer and locate the element. Once you locate the element, disconnect the wires and using an ohmmeter test for continuity on the element. If the element is good you should get a reading between the two terminals, if not the element is bad and it should be replaced. However, if your dryer is overheating, it is doubtful element will have no reading. Next, using your ohmmeter, check each terminal to ground (metal element housing) if you get a reading here your element is grounded out and could be causing you problem.
Some dryers use relays to energize the element as needed. If this relay sticks it can cause the element to stay on continually. This will cause the dryer to overheat, so if your dryer cuts out after a few minutes you could have a bad relay. On some dryers this relay will be mounted to the control panel or maybe mounted near the element (depending on the model). On some dryers, this relay will be mounted on a main board.
Moisture sensors consist of two bars inside the dryer. When wet clothes come in contact with these bars, it shorts the sensor out, thus when the clothes are wet the moisture sensor is constantly being shorted out, “telling” the dryer control the clothes are wet.
Moisture sensors are very reliable and very seldom fail. However, sometimes the wire going to the moisture can break or come loose. If this happens the dryer will sense that the sensor is open, which under normal circumstances, this would mean the clothes are dry, meaning there is no need for the dryer to run much longer (this can make your dryer cut off prematurely).
Also, sometimes the plastic housing the sensor is embedded in will crack and cause the bars to end up too far apart which can cause the same issue.
For the most part, if the housing isn’t cracked and there isn’t a loose wire, the moisture sensor most likely isn’t your issue, however to be sure you can check it. Find a place to disconnect the sensor, on some dryers you can pull the wires off right at the sensor and some you may have to disconnect from the control, in which case you will need to see the wiring diagram to find the wire. Once you have disconnected the sensor, test ohms across the sensor. Be sure the meter is set at the highest ohms setting. It should be an open circuit, and then wipe the sensor with a wet rag. When you wipe the sensor with the wet rag you should get a reading on your ohmmeter.
If your dryer cuts out after a few minutes the motor can be overheating. This could be due to a clogged vent, a bad motor or lint on the motor. Sometimes it can be hard to tell if the motor is overheating but often when the motor is overheating; it will run a few minutes and then cut off. Then if you wait a few minutes, you will hear a faint click coming from the motor, as soon as you hear the click try the dryer and if it runs then it is a good chance the motor is overheating. Sometimes you can’t hear the click, in which case you will have to access the motor and see if it is very hot. If so, try cleaning the motor because sometimes lint can build up on the motor and cause it to overheat.
If you clean the vent out and clean the lint off the motor and it still overheats you have a bad motor.