Re: Dell - 1504FP W/Pictures - new problem

Hi guys,

As luck would have it of the two monitors I fixed, one has come back in when the smoke escaped from another component ... I'm just not sure which component it was. Any ideas what needs to be replaced there? See attached shots) ... and what may have caused it to fail? I suspect that after re-capping and replacing the busted txformers, the unknown component was next in line.

I may be able to get the second monitor back to compare PCBs and identify the burnt component(s) but thought I'd check here...

Hi guys,

I'm a bit stumped here.

-Scrapheap-destined Dell 19" E197fpf monitor that wouldn't power on at all.
-Found the 12V->5V DC-DC converter IC had failed (AP106 ).
It was outputting 11V to the rest of the cct. The 3.3V and 1.85V regulator outputs were still fine.
-I replaced it with a LM2575 1A Fixed-5V version. (). First time the monitor worked beautifully for about 10 minutes then died. Found the 5V regulator had died again.
-Didn't have my ESR meter yet so I replaced most of "secondary-side" electrolytic caps with...

Re: Dell - 1504FP W/Pictures - SOLVED

Hi guys,

Firstly thank you to all contributors - your wisdom really helped!

I had two Dell 1504FPs exhibiting the dreaded "2 seconds to black". I changed caps C17 A,B,C and D... C17 and C23 - but still no luck.

Checked the primary and secondary resistances on T1, T2, T3 and T4 and found the problem. Each monitor had a single transformer whose secondary was higher than the specified 0.9k. They were approx 1.7k and 1.9k respectively. So I removed them.

I took a healthy txformer...