UMD still not reading even with good laser assembly

[seriouslysilly]

Hi all,
I was recently handed a phat to try and fix.
Everything on this PSP works with the exception of reading UMDs.

Bought a few new laser assemblies and can confirm that they work as I have installed them into other phats and have no problems reading.

The strange thing about this psp is that it will state that it can't read the disk immediately after closing.  It doesn't even give enough time for the laser to read it, let alone turn on.
Like I said before, the laser assemblies work so it can't be those.

Has anybody come across a similar problem and can offer some advice on the matter?

Thanks!

[krazyone2006]

is the UMD switch on the back of the motherboard messed up maybe?

[seriouslysilly]

that black little switch?
Not sure but I think it still works.
If I press it down, the psp immediately says that it can't load the game.
So it's detecting that a UMD is inserted.  For some reason it's just saying it can't read immediately after closing and not giving a chance for the laser to read it.

[EliteGamer83]

Try bridging it.

[seriouslysilly]

bridge the pins on the switch?

if I do that, won't it be permanently on the "unable to load" message?

if I hold the switch down or keep the UMD disc in, the message just stays on the screen

[EliteGamer83]

Must be your motherboard then. I said bridge it as when the switch is pushed not all the points are making contact, there are 4 points and(or) meaning there are 2 tracks that need to be connected, so maybe only one of them is making contact to complete the circuit. So you could just take 2 piece of wire in the shape of a U and bridge the switch, if it doesnt work then just take the wire off.