HP 1905 No power. No led. No output voltage.

[alexanna]

Re: HP 1905 No power. No led. No output voltage.

Well I know everyone is going to think I have totally lost it, But
I had a H.P. monitor with similar symptoms and when I had my positive DMM lead hooked to one of the pins of the X201 crystal and the neg. Lead to a ground screw with DC volts selected, the monitor would power on and work. I have no Idea why, But the logic board ended up in the parts box.
This is true , no bull S.
Al.

[newbie1]

Re: HP 1905 No power. No led. No output voltage.

At this point the only thing I can think of is that the EEPROM, U205, got corrupted. According to the schematic, it's a M24C16-MN6T. IF there's a method to perform an EEPROM reset, then that's a possible solution. On some Samsung's you can just replace the old EEPROM with a blank one. I don't know how it works in your case.

thanks jet. i will try to google how to reset it WITHOUT de-soldering it. If this guy is expensive, i don't think i want to risk spending more on a blank one without assurance that it will work. Heading to scrap yard?. or just keep for future use?

Well I know everyone is going to think I have totally lost it, But
I had a H.P. monitor with similar symptoms and when I had my positive DMM lead hooked to one of the pins of the X201 crystal and the neg. Lead to a ground screw with DC volts selected, the monitor would power on and work. I have no Idea why, But the logic board ended up in the parts box.
This is true , no bull S.
Al.

Hey Al, i tried this method of yours just now. BUT sadly mine doesn't work. Well, sometimes, while repairing all these monitors i get it working with some unconventional/weird ways. I remember months back a Samsung with No display, open up but No bad caps, no poor solder joint. I just re-assembled again & it works!!.. & it still going strong.. My solder iron wasn't warm yet.. haha..

[newbie1]

Re: HP 1905 No power. No led. No output voltage.

So far, I could not find any sources on how to hard reset the EEPROM through google. I have measured that U205 is receiving steady VCC. I have checked that this EEPROM is cheap but I am not sure whether the blank one will work. Another thing i observed just now was the Logic Processor is damn hot, touching it on the top side. I am not sure whether this is normal or not. Anybody knows?.

[SURFER7]

Re: HP 1905 No power. No led. No output voltage.

newbie1 did you happen to fix the f1905e LCD

[newbie1]

Re: HP 1905 No power. No led. No output voltage.

Sorry for the late reply guys. Have been busy with the family matters lately.

Hey surfer7. Dude, unfortunately no. Something just gone bonkers in the logic card section (Suspect it is the EEPROM or the processor) but just could not point my finger at any one of them specifically and, plus, i do not have the skill/s to solder/re-solder them. Are you having the same issue as well?

BUT i manage to use the panel & swap it on another HPv19 with specks of dust INSIDE the panel and sold it off. So, at the very least, i got back what i paid for this crappy HP 1905.

[SURFER7]

Re: HP 1905 No power. No led. No output voltage.

I just fixed mine. It was the fuse. 2.5A 250V fuse replaced with a 2A 250V and it worked
the first power on. I found this on the road. http://www.youtube.com/watch?v=BuVxN-ovg-g