Power supply troubleshooting is generally easy to do, but if it's the switch mode type, then prepare to pull your hair out in frustration!
You see, switch mode power supplies (SMPS) are not as easy to fix as the linear ones. Due to the complexity of SMPS circuit designs, many newbie technicians would shy away from working on them.
That's what I did when I first got into the electronics repairing business about a year ago.
Later, I managed to track down a copy of switch mode power supply troubleshooting manual that taught me how to repair a wide variety of SMPS in a bit-by-bit fashion.
I only wish I discovered that manual from the very beginning! Anyway you can click here to give it a look.
It's very detailed so might take some time for you to go through each chapter and repairing lesson.
In the meantime, I want to share with you a few laser-focused tips for troubleshooting any kind of SMPS.
Alright here we go…
Tip Number One
Now, this tip is going to sound very obvious, but it's worth emphasizing because a lot of novice technicians don't do this…
Learn to FULLY interpret schematic/block diagrams. Remember, the keyword here is…"fully". Don't study only specific parts of the diagrams - learn all of them!
This way, you'll be more flexible in dealing with various switch mode power supply troubleshooting and repairing problems.
Tip Number Two
Upon removing the casing of an SMPS unit, one of the first things that I would look for is dark or burnt-like areas. In many cases, a shorted component (due to excessive heat) would often darken its surrounding area.
Diodes like zener and schottky as well as power ICs are susceptible to this problem. So make sure you inspect those darken areas!
Tip Number Three
How is your sense of smell? Sorry…I ask you this because in order to detect a very common yet often overlooked SMPS problem, you need to have a rather keen sense of smell.
Burnt coil is a very common issue but it's not easy to detect if the damage occurs in the internal winding section. That's why you need to smell it!
However if your sense of smell is not working so well, don't worry…I can't smell very well either because I used to smoke for 15 years (just quit recently)!
Anyway, if smelling is a problem, then simply use the blue ring tester to determine if the internal winding part is burnt.
And once again, if you need more in-depth help in conducting switch mode power supply troubleshooting, just follow this link to get a detailed repair guide that's quite crammed with instructional photos.
You can actually download it direct to your computer so no shipping required. Go ahead and click this link.
