LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • yomamaphat
    Member
    • Jun 2010
    • 12

    #1

    LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

    Hi all,

    This is from a PowerMac G5 Quad 2.5GHz. I wasn't there when it died, so I don't know of any smells or sounds that might have occured. Inside it looks clean though, can't see any vent marks, signs of heat, or anything.

    The big black caps are "Ltec", some of the smaller brown ones are "taicon" and "Ltec" and some don't seem to say their brand as explicitly.

    I power it on by shorting green, like I have with ATX powersupplies, although this has bizarre connectors it still works.

    A relay clicks, the fans twitch then stop. A few seconds later a steady buzz starts and continues until I unshort the green. The buzz is coming from right near the relay (maybe the black thing behind it? "L1"? silkscreened on the PCB).

    I measured what happens to the voltage on the 5 and 12 V wires. The 5V spikes up to 1 - 3 volts and then falls quickly to zero. The 12V barely goes up at all, just showing < .05V

    I haven't looked at the underside yet, but will soon. Any ideas? What to test next?

    Thanks in advance!
    Attached Files
  • yomamaphat
    Member
    • Jun 2010
    • 12

    #2
    Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

    It's not L1 that would be buzzing, maybe BD1 (can rectifier bridges buzz?).

    Comment

    • stj
      Great Sage 齊天大聖
      • Dec 2009
      • 30951
      • Albion

      #3
      Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

      only coils can buz.

      Comment

      • yomamaphat
        Member
        • Jun 2010
        • 12

        #4
        Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

        Well I have thoroughly looked at both sides for physical damage and can't find anything. Can I test the switching transistors without removing them like this guy says?: http://www.mikesarcade.com/cgi-bin/s...e=psrepair.txt

        I know I have not given much info to trouble shoot with, but any suggestions on what I should first start testing would be appreciated. Is the above guide a good place to start?

        Thanks!

        Comment

        • stj
          Great Sage 齊天大聖
          • Dec 2009
          • 30951
          • Albion

          #5
          Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

          the fan twitch makes me suspect there is a short-circuit shutting the supply down.

          can you start the psu when it's not connected to the motherboard?

          Comment

          • yomamaphat
            Member
            • Jun 2010
            • 12

            #6
            Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

            No, seems like the same results connected or disconnected.

            Comment

            • stj
              Great Sage 齊天大聖
              • Dec 2009
              • 30951
              • Albion

              #7
              Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

              disconnect it and meter the resistance between ground and each voltage line on the plug.

              see if one looks a lot lower than the others.

              Comment

              • yomamaphat
                Member
                • Jun 2010
                • 12

                #8
                Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

                I got 1.65k on the 5V, 940 on the 3.3V. On 12A & B I get 3.1k. (all these use the chassis ground)

                On the 12mpu1 & mpu2 I get just 2 ohms to its grounding line. (This has it's own isolated ground apparently. To the chassis I get 22.1k from the either positive and negative.)

                Should I try to trace which components are in line with the 12V mpu rail and maybe do some pulling and testing?

                Comment

                • stj
                  Great Sage 齊天大聖
                  • Dec 2009
                  • 30951
                  • Albion

                  #9
                  Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

                  yes, start with the main diode(s) from the transformer to the 12vmpu lines.
                  if the diode isnt shorted then check the caps.

                  Comment

                  • yomamaphat
                    Member
                    • Jun 2010
                    • 12

                    #10
                    Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

                    I found damage, hopefully not caused by me. It's in a spot where I don't think I did it. I'm not sure why I missed it when looking the unit over initially though...

                    I believe the main diode is OK.
                    I have no ESR meter for testing caps, but my dad in another state might and I'll be moving there in a couple weeks. I'll probably put this on the back burner until I make my move.

                    Thanks for the help so far.
                    Attached Files

                    Comment

                    • stj
                      Great Sage 齊天大聖
                      • Dec 2009
                      • 30951
                      • Albion

                      #11
                      Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

                      you dont need an esr meter to find a short,
                      remove the suspect part and meter from the connector to see if the 2ohm reading goes up.

                      Comment

                      • yomamaphat
                        Member
                        • Jun 2010
                        • 12

                        #12
                        Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

                        Cool, that's a good idea. I'll do that when I get moved. Probably 2 - 4 weeks. Thanks again.

                        Comment

                        • Toasty
                          Badcaps Legend
                          • Jul 2007
                          • 4171

                          #13
                          Re: LiteOn 1000W Model: PA-5102-1-LF Part no. 614-0336

                          Bloody hell. Put the name of the system and PSU in the thread ~somewhere~. The TITLE is a good start.

                          Teslaconverter Tesla converter Apple PowerMac Power Mac G5
                          veritas odium parit

                          Comment

                          Related Topics

                          Collapse

                          • cheeky2
                            Dell XPS One 2720 AIO Liteon PS-3261-9DA not starting up immediately
                            by cheeky2
                            I suspect the issue is with the power supply Liteon PS-3261-9DA as apparently they are notorious for issues with them. Has anyone else had similar issues where the PC tries to boot up a few times before finally booting up. Now I have opened up the PSU which shows no signs of any capacitors failing. I did remove one capacitor that looked to have an issue however with my peak meter it showed it was within the limits with good very low esr values which was somewhat disappointing!
                            I am going to put a Meter leads across the outputs to see how stable they are when it occurs to see what they are...
                            11-20-2024, 06:52 AM
                          • jm1234
                            opto something Liteon 816A4
                            by jm1234
                            Hi,
                            I'm troubleshooting a power supply board and one opto coupler seems shorted. It's a through-hole, marked with 3 lines:
                            1223
                            816A4
                            W
                            I'm not sure what replacement to buy for it. It resembles LTV-816 (https://www.tme.eu/sk/en/details/ltv...output/liteon/), but I'm not sure it's 100% that. The data sheet shows multiple sub-types like 816M, 816S, but 816A is not there.
                            I do have other functional pieces on the same board, so I could do some measurements on those, but I'm not sure what to check.
                            Any idea appreciated.
                            05-20-2024, 03:30 AM
                          • MikeCebula
                            Apple 24" iMac A1225 Liteon PA-3241-02A1 schematic and boardview
                            by MikeCebula
                            Request schematic and possibly boardview for Apple 24" iMac A1225 Liteon PA-3241-02A1

                            Thank you,
                            Mike
                            11-04-2023, 10:18 PM
                          • s_henya
                            Liteon PA-12617 dead (Lenovo ideacentre3)
                            by s_henya
                            Hi Guys,
                            Trying to save this PSU from going to the bin.
                            PSU was found dead:
                            1.. Main fuse blown
                            2. Main switching transistor shortes
                            3. rectifier bridge shorted
                            4. low ohm resistor blown

                            replaced all of the above (resistor was replaced with a. Thin wire since i don't know what was the original value)

                            Have 330v on main cap. But standby is still not right.

                            maybe the driver chip died?...
                            09-06-2024, 03:15 AM
                          • antoniu200
                            New Headset with TRRS 3.5mm making a subtle buzz
                            by antoniu200
                            Hi! So, I recently had my Plantronics headset die (one 3 pole connector for the mic, another one for the headphones), because of the bad quality potentiometer, so I bought myself a new headset: a JBL Tune 500 (one 4 pole connector for both the mic and headphones). All great and dandy, until I notice a subtle buzz sound (~60Hz, very, very low dB) coming out of them when I connected them to my PC, but the sound wasn't present on my phone. Now, the first thing I tried was replacing my front 3.5mm jacks. After replacing them, the sound was still there.

                            Did some digging, and found out...
                            Front Panel PCB
                            0%
                            0
                            3.5mm front sockets
                            0%
                            0
                            The adapter
                            0%
                            0
                            Plantronics headset had a ground loop isolator (hence the quieter sound coming out of them)
                            0%
                            0
                            09-06-2019, 06:29 AM
                          • Loading...
                          • No more items.
                          Working...