Re: W241D (W240D) flickering Problem

Well, I hinted that I'd be back last January 2016... and here I am again with a flickering W241D. In other words, the repair lasts for around 5-6 years before it needs to be repeated. That hint about the missing HF blocking capacitor looks interesting so that will be my first approach, more later...

Re: W241D (W240D) flickering Problem



Replacing the two 100uF/16V SMD capacitors marked by red circles in Leontius' post earlier on this page solved the problem for me, after having gone through some earlier, partly successful (but in retrospect probably futile) steps.

I measured the capacitance and ESR for those caps I removed. One measured at 76uF/7 ohm, the other was 82uF/13 ohm - in other words, they were past due. As I did not have any 100uF capacitors handy I replaced each by two 47uF/25V (axial electrolytic) in parallel. The ESR for the replacements...

Re: W241D (W240D) flickering Problem

As to the temperature around those capacitors I can only guess, but - given that these monitors seem to fail because of insufficient cooling - it is probably higher than 55°C but a lot lower than 105°C. The total parts expenditure for replacing the secondary side capacitors lies somewhere around 5-6 € when bought in smaller quantities, much lower when bought in bulk. Given that the device is in a disassembled state to replace the regulators, replacing those capacitors is not that much more work. The monitor would certainly have worked without...

Re: W241D (W240D) flickering Problem

I got one of these monitors for free because it had the jitterbug. In this case it was caused by a faulty - ie temperature-sensitive - 1.8V regulator on the main board. The diagnosis was rather easy: wait 'till the monitor starts jumping, spray some cooling spray (I used electronic cleaner (Isopropyl Alcohol) spray as I do not have 'real' freezing spray) on the suspected component and observe. It stopped jumping around for a bit. The opposite of this method also works: turn the thing on when it is totally cold, the image should be fine. Now point...