If I have a multimeter that can measure current, voltage, capacitors, resistors, ..etc., how can I detect the damaged component(s) in a PCB?
I try to visually detect if there are any damaged components such as a blown fuse, broken resistor, black components (due to excessive heat), weak wire welding, or sockets that are uninstalled properly.
I try to find if there are any short circuits using the multimeter. I test the terminals of every transistor, resistor, ...etc.
The worst part is that I measure the values of each component and see if the measured value matches the written value or not. But "loading effect" here is very annoying because I might measure a damaged capacitor but the measurement is close to the right one due to loading effect. I might measure a healthy capacitor but the measurement is incorrect due to loading effect as well.
I don't know how to test ICs.
Sometimes, I meet new weird components that I've never seen before. Of course, I don't know how to test them.
The three approaches that I mentioned are not effective at all especially when it's a big PCB and have a lot of components.
So how can I do effective maintenance to different electrical devices?