A customer asked me to look at a controller board PCB from a split air con system. It generates an error code, but I don’t know if the fault is on this PCB or elsewhere. Learn how to spend an hour to methodically work through the PCB with a multimeter, what can we test, what can’t we test, and how to locate the faulty component. These techniques will allow you to fix a lot of PCBs without schematics.
Previous repair video on this Air Con (outdoor controller PCB)
DIY TL431 Tester
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Equipment used in my videos. These are affiliate links, you pay the normal price and I make a small commission.
ANENG AN8009 MULITIMETER
VC480C+ MILLIOHM METER
MESR-100 ESR METER
XC6013L CAPACITOR METER
LCR-T4 COMPONENT ANALYZER
FNB58 USB ANALYZER
TL460S PLUS PCI_E ANALYZER
TOOLTOP ET120MC2 SCOPE
FNIRSI 1014D SCOPE
NPS3010W 30V 10A PSU
T12 STATION WITH M8 9501 HANDLE
M8 9501 HANDLE
YIHUA 982 Soldering Station C210/C245
FNIRSI HS-02 PORTABLE SOLDERING C210/C245
QUICK 861DW
PROS’KIT SS-331H
INFIRAY P2 PRO IR CAMERA + MACRO LENS
TOOLTOP ET13S THERMAL CAMERA METER
ET13S MACRO LENS
OPTICAL MICROSCOPE
TOMLOV TM4K AF FLEX
TL866 II+ PROGRAMMER
CH341 PROGRAMMER
NC-559-ASM FLUX
DESOLDER BRAID (I use size 8045)
HX-T100 SOLDER (0.6MM)
ESD-11 TWEEZERS
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Thank you
Richard
به وضوح این روش برای عیب یابی ساعت ها و روزها به طول خواهد انجامید و شاید هرگز خرابی پیدا نشود
So at the 20:31 mark of this video you are testing a component and when you touch it with your prob it moves ever so slightly. But the slight move is probably a broken solder joint on the opposite side of the board. Just a heads up in case you missed it.
Action actually happens at 13:00. Good learning video.
I went to college for electronics engineering and cannot say enough how much I hate trouble shooting and repairs lol. I didn’t finish my degree, but that doesn’t change the reality that I went to create from scratch, not fix from old lol.
It’s a very, VERY challenging skill and education to be a competent electronics repair technician.
The reality is, to be the best engineer designing from the ground up? Nothing will make you the best of the best like fixing any random electronics “crap” lol.
You learn particular IC’s by model that are prone to particulars, why particular diodes are used over others, what caps are usually bad in conjunction to an IC you know well and on and on it goes.
It gives you a depth of insight, foresight and prediction to then produce new products that won’t be prone to the troubles of the past.
So much electronic equipment is made to a disposable standard. I have a three year old Xerox laser printer and guess what, the spares are not available, what a waste of resources!