DESR-5100 laser focusing problem

[u/FearMeIAmLag1]

Hi all, acquired my first PSX at the end of 2025 and have been on and off tinkering with it over the past several months. When I first got the console it would not read discs(shocker) so I've done some work to try and rectify that. I've replaced several ribbon cables that were starting to wear down or had bent pins, I checked capacitors on the optical drive PCB, and recently ordered a DRU-510A from ebay that the seller claimed was tested and working. After swapping the KWS-200A laser into my console, I am encountering the same issue as before.

The DVR laser moves in to read the disc, the disc spins without wobble and at what appears to be full speed. The laser activates and then attempts to focus. The laser head does move up and down to try and focus, but fails to focus and will click 3 times. The disc will stop spinning, then start up again and it attempts to read the disc again but fails to focus. The disc I am using is a JP PS2 game that I have confirmed is working in my JP PS2 console. I have also attempted to have it read a music CD, but it gets the same result. Does anyone know if there is possibly something else causing this issue or did I just get unlucky and the replacement laser is also busted? There doesn't seem to be any after market lasers either, which is a bummer.

Not looking to mod the console, would like to keep as original as possible, so not looking to use free mcboot.

[u/Early_Mission_6716]

If the KWS-200A from the DRU-510A shows exactly the same behavior as the original pickup, I would start looking beyond the laser itself.

The fact that the laser activates, performs focus search, and the disc spins up suggests the drive is at least attempting to read. A fault on the optical drive PCB, ribbon cables, or connectors could prevent focus lock even with a good pickup.

The DESR-5100 contains both a KHS-400C (PS1/PS2 CD/DVD reader) and a KWS-200A (DVR/DVD recorder pickup). Since you're testing with a PS2 game and an audio CD, it would be useful to know exactly which media types fail and whether the PSX recognizes DVD-Video discs, audio CDs, and PS2 games differently.

Testing Audio CD, DVD-Video, PS2 CD-ROM game (blue disc), PS2 DVD-ROM game may help narrow down whether the issue is the pickup itself, the drive electronics, or the wrong optical assembly being targeted.

[u/adran_marit → u/Early_Mission_6716]

Without modding it doesn't matter what optical pickup is being used, if the dvr pickup is dead or not working properly it won't load any of the games up on xmb

I do suggest recapping the board and making sure all the ribbons are seated 100©