PX-716UF malfunctioning?

So after extensive research on this forum and consulting the QPxTool website, I started to search for BenQ DW-1650s and PX-716As for use with an IDE-USB adapter (or, eventually, enclosure) for CD quality scanning purposes. Then, I found a PX-716UF (did not even know it existed) on shopgoodwill.com and won the auction @ $10.99 (ended up paying exactly $25 in total in the end). Today I unboxed it and connected it to my desktop and immediately after turning it on I noticed a high-pitched whining noise; it is constant and persists no matter what the drive is doing or not doing. Obviously, that did not seem very promising to me but nevertheless I inserted a data CD-R (CMC Magnetics) I burned recently with my WH16NS40 (fw 1.03). QPxTool reports “no media” for the PX-716"A" and no CD shows up in the file manager either (except for the disc in my WH16NS40 currently). I just tried a pressed audio CD and I get exactly the same results. After inserting a CD (again, for both discs) the status LED is constantly on for some seconds and green. Then, it starts somewhat rapidly blinking orange or amber 2 times before pausing briefly and repeating this continuously.

After seeing another PX-716UF thread I checked and the included PSU is a Plextor branded unit rated for 12 VDC/3A. I should also mention that I have verified that the whining noise comes from the drive itself and not the PSU. I see there is a “self-test” switch but I am not sure if I need Plextools to view the results (I only run Linux on this desktop as I do not have a Windows license for it and my only computer with Windows runs Windows 10). I do not know if the drive even came with a Plextools disc; I believe it only came with Roxio Toast and WinDVD discs.

Blinking amber led in Plextors means that the drive can not identify the disc correctly. I had the same problem with 3 Plextor 716A’s. I know these drives are recommended but i had a lot of problems with them. Later on i bought 3 Plextor 760A and these run fine. Your drive is old and most likely the laser is worn out.


Self-test instructions from the manual:

Using the PX-716UF Self-Test Diagnostics

The PX-716UF contains a set of self-test diagnostics that can help isolate trouble and determine if a problem is in the drive or elsewhere.

What You’ll Need

To perform the tests you’ll need a blank piece of Plextor-recommended DVD+R, DVD-R, or CD-R media. (See “Recommended Media” on page 81 or visit our web site.) The self-test will write to this media, so you won’t be able to use this disc again.

Performing the Self-Test

This tests three functions of the drive: writing at maximum speed, continuous playback at maximum speed, and random access. To perform the CD write/read test:

  1. Unplug the USB or FireWire cable from the rear of the Plextor PX-716UF drive. CAUTION: Failure to disconnect the USB or FireWire cable before starting the test could result in system data loss.
  2. Set the PX-716UF drive’s power switch to OFF (so the “0” is depressed).
  3. Slide the SELF TEST switch to the left (ON) position. Use a pen point, paper clip, or other similar object.
  4. While pressing the eject button, set the PX-716UF’s power switch to ON (the “1” is depressed). The front-panel disc/busy indicator blinks green and amber, and the disc tray opens.
  5. Insert a blank Plextor-certified DVD+R, DVD-R, or CD-R disc. Be sure to use only media of the type recommended by Plextor. Then close the disc tray. If the disc/busy indicator blinks amber three times, the loaded disc is not a blank DVD+R, DVD-R, or CD-R disc. Remove the disc and insert a blank, Plextor-certified recordable disc.
  6. The drive begins the diagnostic routine. Upon completion of the diagnostic, you see the results:
  • If there was no problem, the disc is ejected automatically. (That is, the disc tray opens, allowing you to remove the disc.)
  • If there was a problem, the disc is not ejected, and you see the disc/busy indicator blink green. One green blink indicates a write or read error. Two green blinks indicate an initialization error.
  1. If the disc was not ejected automatically, press the eject button to eject the disc.
  2. Turn the PX-716UF power switch to OFF, and set the SELF-TEST switch to the right (OFF) position.
  3. Turn the PX-716UF’s power switch to ON (so the “1” is depressed).
  4. Reconnect the USB or FireWire cable from your PX-716UF drive to the computer.

What the Self-Test Results Indicate

• If a drive passes the self-test, then the drive’s operation is OK.
• If the drive fails the self-test, in some cases the problem may be caused by the media. Try the self-test again using a different brand of DVD±R or CD-R media; if the drive passes the self-test this time, the drive is OK.

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Plextor had an early TLA run of 716A’s having bad OPU’s. I bought a new-old-stock specimen off eBay a while back, factory sealed, which would not recognize any disc and got refunded. It stands to reason there might be 716U/F’s having the same internals and the same issues.

I’ve posed the full diangostic instructions for the external unit above.

A lot of other people probably know a lot more about the history of Plextor and what lead them to stop making their own drives, but my personal experience with later Plextor drives has made me feel like they ceased trying before they ceased manufacturing. My old, old Plextor CD-ROM and CD-RW drives (from the 90’s) seem like they’re all going to last forever. My newer, closer-to-when-Plextor-called-it-quits PX-760 and PX-716 drives all seem like they’re looking for an opportunity to die. Beyond my anecdotal experience, I gather that these later drives are known to have a decently high failure rate on OPUs, because there’s a note on the Redump Wiki that says “The Plextors in the 700 range that can read DVDs have firmware bugs and the lasers can go bad.” I dunno what the firmware bugs are, but I’ve definitely had some lasers go bad.

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Just wanted to explicitly thank everyone for replying. I have contacted Goodwill and will let you know how it goes. I probably will get a new old stock Optiarc AD-7200S or one of the rebadged models as I want one anyway for burning and I have read it is decent for CD quality scanning and I do not want to really gamble with another old IDE drive. Only problem is I will have to buy another pricey ($55) OWC Mercury Pro enclosure (Adorama sells them with WH16NS40s installed, which is how I got my first one) as my desktop case does not have a 5.25" bay…