Need help with a Lite-On DVD writer

vbimport

#1

Hi, I bought a Lite-On SOHW 1653S DVD writer with both laser power adjusting potentiometers broken. I managed however partially adjusting the one for DVD, but it’s right on the edge of the still existing part of the potentiometer, (around 200 Ohms) so the drive only reads DVDs with difficulty. On the CD side, the case is even worse. Half of the potentiometer is missing, and I can’t make it recognize any disc.
Please if someone could help me out, by measuring the resistance of both potentiometers on a similar unit, I could replace them with fixed value resistors.
:bow:


#2

Maybe you can guides us where to mussure. :wink:

My recommendation to you is; replace this old in many aspects problematic drive with something better… :smiley:


#3

Ok, you have to take apart the unit by pulling down only the bottom side.
Than you have to pull out the disc rotating motor cable, (very simple operation, just be carefull to loose first that brown holding clip)
than gently lift up the pcb (there are 2 white holding clips in one side), and rotate until you see thee the 2 tiny potentiometers. (you have tu push the head towards the disc rot. motor for a confortable work)
The resistance can be measured between the middle and one side pin. (the other one is connected to the middle pin, so you measure 0 Ohms)
The whole operation takes no longer than a few minutes.
BTW, I dont want to trash it, it’s (will be - I hope) fully functional.
Many thanks again!


#4

anybody???


#5

I was googling for a solution on how to trim laser potentiometers for my old burner which cannot read dvds and I ended up here.
I am sorry that szabi has been left with no answer. The pot closer to the right side of the PCB measures 180Ω and the other one that is more inside the PCB measures 217Ω.

And is there anyone who has actually done pot trimming on DVD burners? I’d like to prolong my burner’s life a bit more.
Since I have nothing to loose (this being my old drive) I’m in for some action.


#6

And I just did it.
I decreased the resistance of both pots a little bit and now my drive can read dvds again. So if you have an old burner that stopped reading one type of discs (CD/DVD) you can do this trick.

Decreasing should be done in small steps and then check for the results. In my case (Sony DW-23A@LiteOn 1653S) the values are as follows:

[ul]
[li]default value of 217Ω trimmed down to 182Ω[/li][li]default value of 180Ω trimmed down to 162Ω[/li][/ul]

Since I didn’t know what pot is for what (szabi mentions that one is for DVD and another for CD laser) I had to adjust both of them.
But I also noticed that if you go too low with values, discs won’t read again.
For example, values of 164Ω and 133Ω (respectively for each pot) are no go for this drive.

I hope somebody else shares their experience with fixing drives this way. Although it’s said to be a temporary fix, I’ve read people reporting their drives serving as long as one year after the intervention.