Checking electronic components

[A.N.O]

hi guys
I have some questions in electronic circuit maintenance and I need your help please.
can I check the capacitor and Inductors in circuit by multimeter?
how I can check the ICs in circuit when I don't have datasheet?

thanks advance

 

[ahmad1954]

if check capacitor and inductor in circuit, probably you don't acquire exact result because other elements have affect to these elements.
what IC do you want to check?

 

[A.N.O]

that is right,but I wonder If I have circuit don't work well how I can know that the wrong in a capacitor or in a second part.

thanks

 

[jiripolivka]

that is right,but I wonder If I have circuit don't work well how I can know that the wrong in a capacitor or in a second part.

thanks

It is often almost impossible to test installed components in a circuit. First you need the schematic, and with a voltmeter or better an oscilloscope you can test voltages in important points like inputs and outputs. In=circuit testing of capacitors, inductors and resistors is always affected by presence of other components. ICs can be damaged if you try to use an ohmmeter as it can apply dangerous voltages or currents in it.
Schematics, data sheets and experience is a good combination for testing but it often fails. The best way is to compare a good and bad circuit board if you have a chance. Most industrial circuit testers work that way.

 

[A.N.O]

thanks.....

 

[kam1787]

often you can narrow down the possible bad components;

1 - visual inspection
2 - smell !!!
3 - use a multimeter to put components in one 0f 3 groups; believed good, believed suspect, believed bad
4 - pull the believed bad components out, then test out of circuit
5 - if that fails, go after the believed suspect

 

[A.N.O]

often you can narrow down the possible bad components;

1 - visual inspection
2 - smell !!!
3 - use a multimeter to put components in one 0f 3 groups; believed good, believed suspect, believed bad
4 - pull the believed bad components out, then test out of circuit
5 - if that fails, go after the believed suspect

thanks for your help