Most often, there are resistor malfunctions associated with the burnout of the conductive layer or a violation of the contact between it and the collar. For all cases of defects, there is a simple test. Let's figure out how to check the resistor with a multimeter.
Types of multimeters
The device is pointer or digital. The first does not require a power source. It works as a microammeter with switching shunts and voltage dividers in the specified measurement modes.
The digital multimeter shows on the screen the results of comparing the difference between the reference and measured parameters. It needs one that affects the accuracy of measurements as it discharges. It is used to test radio components.
Types of faults
A resistor is an electronic component with a specific or variable value of electrical resistance. Before checking the resistor with a multimeter, it is inspected, visually checking the serviceability. First of all, the integrity of the hull is determined by the absence of cracks and chips on the surface. Leads must be securely fastened.
A faulty resistor often has a completely burnt surface or partially in the form of rings. If the coating has darkened a little, this does not yet characterize the presence of a malfunction, but only indicates its heating, when the power released on the element at some point exceeded the permissible value.
The part may look like new even if the contact breaks inside. Many people have problems here. How to check the resistor with a multimeter in this case? It is necessary to have a circuit diagram, according to which voltage measurements are made at certain points. To facilitate troubleshooting in the electrical circuits of household appliances, control points are highlighted with an indication of the value of this parameter on them.
Resistors are checked last, when there is no doubt about the following:
- semiconductor parts and capacitors are intact;
- there are no burnt tracks on printed circuit boards;
- there are no breaks in the connecting wires;
- connector connections are secure.
All of the above defects appear with a much higher probability than the failure of the resistor.
Characteristics of resistors
The resistance values are standardized in series and cannot take any values. Permissible deviations from the nominal value are set for them, depending on the manufacturing accuracy, ambient temperature and other factors. The cheaper the resistor, the greater the tolerance. If, during the measurement, the resistance value goes beyond its limits, the element is considered faulty.
Another important parameter is the power of the resistor. One of the reasons for the premature failure of a part is its incorrect choice for this parameter. Power is measured in watts. It is chosen the one for which it is designed. On the symbol diagram, the power of the resistor is determined by the signs:
- 0.125 W - double slash;
- 0.5 W - straight longitudinal line;
- Roman numeral - power value, W.
The replacement resistor is selected according to the same parameters as the faulty one.
Checking resistors for compliance with ratings
To check, you need to find the resistance values. They can be seen by the serial number of the element on the diagram or in the specification.
Resistance measurement is the most common way to test a resistor. In this case, compliance with the face value and tolerance is determined.
The resistance value must be within the range set by the switch on the multimeter. The probes are connected to the COM and VΩmA jacks. Before checking the resistor with a tester, the serviceability of its wires is first determined. They are closed together, and the device should show a resistance value equal to zero or a little more. When measuring low resistances, this value is subtracted from the instrument readings. 
If the energy of the batteries is not enough, the resistance is usually different from zero. In this case, the batteries should be replaced as the measurement accuracy will be poor.
Beginners, not knowing how to check the resistor for performance with a multimeter, often touch the probes of the device with their hands. When values are measured in kiloohms, this is unacceptable, since distorted results are obtained. Here you should know that the body also has a certain resistance.
When the device fixes the resistance value equal to infinity, this is an indicator of the presence of a break (on the screen "1" is lit). It is rare that a resistor has a breakdown when its resistance is zero.
After measurement, the obtained value is compared with the nominal value. This takes into account the tolerance. If the data matches, the resistor is good.
When there are doubts about the correctness of the readings of the device, you should measure the resistance value of a good resistor with the same rating and compare the readings. 
How to measure resistance when the value is unknown?
Setting the maximum threshold when measuring resistance is optional. In ohmmeter mode, you can set any range. The multimeter will not fail because of this. If the instrument reads "1", which means infinity, the threshold should be increased until the result appears on the screen.
Calling function
And how to check the resistor with a multimeter for serviceability? A common way is dialing. The switch position for this mode is indicated by a signal diode icon. The sign of the signal can be separately, the upper limit of its operation does not exceed 50-70 ohms. Therefore, resistors whose values exceed the threshold do not make sense to ring. The signal will be weak and may not be heard.
At circuit resistance values below the limit value, the device emits a squeak through the built-in speaker. The continuity is done by creating a voltage between the points of the circuit, selected using probes. For this mode to work, you need suitable power sources. 
Checking the health of the resistor on the board
Resistance is measured when the element is not connected to the rest in the circuit. To do this, you need to release one of the legs. How to check a resistor with a multimeter without soldering it out of the circuit? This is done only in special cases. Here it is necessary to analyze the connection diagram for the presence of shunt circuits. Semiconductor parts especially affect the readings of the device. 
Conclusion
When deciding how to check a resistor with a multimeter, you need to figure out how electrical resistance is measured and what limits are set. The device is intended for manual use and you should remember all the methods of using the probes and the switch.