Acer 42" LCD tv no power or stdby light

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  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #21
    Re: Acer 42" LCD tv no power or stdby light

    Just trace out the connections from the Gates back to the IC pins. You should get the P/N of that SMPS IC to get the pin out.
    Never stop learning
    Basic LCD TV and Monitor troubleshooting guides.
    http://www.badcaps.net/forum/showthr...956#post305956

    Voltage Regulator (LDO) testing:
    http://www.badcaps.net/forum/showthr...999#post300999

    Inverter testing using old CFL:
    http://www.badcaps.net/forum/showthr...er+testing+cfl

    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
    http://s807.photobucket.com/user/budm/library/

    TV Factory reset codes listing:
    http://www.badcaps.net/forum/showthread.php?t=24809

    Comment

    • slowcap
      Member
      • Feb 2013
      • 15
      • nz

      #22
      Re: Acer 42" LCD tv no power or stdby light

      UPDATE:

      receiver the new mosfet's today, decided to not replace the driver ic as was willing to take the risk, soldered in the new fets and the old bridge rectifier, new fuse and plugged it in, to my surprise no pops or explosions, and the standby light is now on, so I pressed the power button on the remote and the light turned green, and that was it, no picture and no sound, I checked and there is no 24v for backlight and no 12v from power board, so all I have is 5v, there is .4v on the 24v line from the board to backlight, where to next? , I have bought a 2 channel oscilloscope , just waiting on a 100mhz probe. will now search for now 24v power problems while awaiting for a reply.

      Comment

      • budm
        Badcaps Legend
        • Feb 2010
        • 40746
        • USA

        #23
        Re: Acer 42" LCD tv no power or stdby light

        You can still have bad SMPS IC300 hwich drives the MOSFETs. Did you trace out the connection and components as I suggested between the Gate and the output Gate drives of the SMPS IC.
        Do you also get 380VDC on that large filter cap on the hot side when you power up the TV?
        Never stop learning
        Basic LCD TV and Monitor troubleshooting guides.
        http://www.badcaps.net/forum/showthr...956#post305956

        Voltage Regulator (LDO) testing:
        http://www.badcaps.net/forum/showthr...999#post300999

        Inverter testing using old CFL:
        http://www.badcaps.net/forum/showthr...er+testing+cfl

        Tear down pictures : Hit the ">" Show Albums and stories" on the left side
        http://s807.photobucket.com/user/budm/library/

        TV Factory reset codes listing:
        http://www.badcaps.net/forum/showthread.php?t=24809

        Comment

        • slowcap
          Member
          • Feb 2013
          • 15
          • nz

          #24
          Re: Acer 42" LCD tv no power or stdby light

          hi, I did follow both gates and both go to the IC300, I soldered a wire to the +ive and the -ive side of the large cap and checked the voltage when pluged in, and its 349 at rest then 415vdc when turned on
          Last edited by slowcap; 04-18-2013, 01:53 AM.

          Comment

          • budm
            Badcaps Legend
            • Feb 2010
            • 40746
            • USA

            #25
            Re: Acer 42" LCD tv no power or stdby light

            The PFC is working but the 12/24V SMPS IC is not working.
            Never stop learning
            Basic LCD TV and Monitor troubleshooting guides.
            http://www.badcaps.net/forum/showthr...956#post305956

            Voltage Regulator (LDO) testing:
            http://www.badcaps.net/forum/showthr...999#post300999

            Inverter testing using old CFL:
            http://www.badcaps.net/forum/showthr...er+testing+cfl

            Tear down pictures : Hit the ">" Show Albums and stories" on the left side
            http://s807.photobucket.com/user/budm/library/

            TV Factory reset codes listing:
            http://www.badcaps.net/forum/showthread.php?t=24809

            Comment

            • slowcap
              Member
              • Feb 2013
              • 15
              • nz

              #26
              Re: Acer 42" LCD tv no power or stdby light

              Is that the ic300 ?

              Comment

              • slowcap
                Member
                • Feb 2013
                • 15
                • nz

                #27
                Re: Acer 42" LCD tv no power or stdby light

                I have ordered a new ic300 chip, it part number is DLA001D pwm controller, will update when I put it in.

                Comment

                • budm
                  Badcaps Legend
                  • Feb 2010
                  • 40746
                  • USA

                  #28
                  Re: Acer 42" LCD tv no power or stdby light

                  Did you look REAL close at all the resistors and Diode on the output pins of the IC which drive the Gate of the MOSFETs, when MOSFET shorted out that bad, those components will be damaged also.
                  Never stop learning
                  Basic LCD TV and Monitor troubleshooting guides.
                  http://www.badcaps.net/forum/showthr...956#post305956

                  Voltage Regulator (LDO) testing:
                  http://www.badcaps.net/forum/showthr...999#post300999

                  Inverter testing using old CFL:
                  http://www.badcaps.net/forum/showthr...er+testing+cfl

                  Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                  http://s807.photobucket.com/user/budm/library/

                  TV Factory reset codes listing:
                  http://www.badcaps.net/forum/showthread.php?t=24809

                  Comment

                  • slowcap
                    Member
                    • Feb 2013
                    • 15
                    • nz

                    #29
                    Re: Acer 42" LCD tv no power or stdby light

                    well its time for an update, I received the ic300 chip for $4 including shipping to New Zealand, soldered it in and tried it out, guess what. Its fixed and back to itself, thank you very much Budm for your help and diagnosis.

                    Comment

                    • budm
                      Badcaps Legend
                      • Feb 2010
                      • 40746
                      • USA

                      #30
                      Re: Acer 42" LCD tv no power or stdby light

                      Thanks for the repair feedback, great work getting it working again.
                      Can you give the link to where you get the IC from?
                      Never stop learning
                      Basic LCD TV and Monitor troubleshooting guides.
                      http://www.badcaps.net/forum/showthr...956#post305956

                      Voltage Regulator (LDO) testing:
                      http://www.badcaps.net/forum/showthr...999#post300999

                      Inverter testing using old CFL:
                      http://www.badcaps.net/forum/showthr...er+testing+cfl

                      Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                      http://s807.photobucket.com/user/budm/library/

                      TV Factory reset codes listing:
                      http://www.badcaps.net/forum/showthread.php?t=24809

                      Comment

                      • brnrubbr
                        Member
                        • Jun 2013
                        • 37
                        • United States

                        #31
                        Re: Acer 42" LCD tv no power or stdby light

                        FYI, narrowed down an issue for a 42" Vizio to a bad DLA001D. Replaced the IC with a STMicroelectronics L6598D. All is well!

                        Issue: 5VDC good, 12VDC bad, 24VDC bad on power board.

                        Comment

                        • Maxamus58
                          New Member
                          • Jan 2011
                          • 3

                          #32
                          Re: Acer 42" LCD tv no power or stdby light

                          I am planning to replace this same IC on my 42" Acer. I have a rework station but I am not seeing any softening of the solder at 200 C (air) can anyone point me to a description of the best method of replacing this SMD. I'd like to know what temperature is safe and how long before I should expect to see the solder soften.

                          ChipQuik seems great but a little expensive for only occassional repairs.

                          Comment

                          • budm
                            Badcaps Legend
                            • Feb 2010
                            • 40746
                            • USA

                            #33
                            Re: Acer 42" LCD tv no power or stdby light

                            200C is too low.
                            sincde when hot air leave the nozzle, it will cool down a bit so you will have to set it a little higer.

                            http://electronics.stackexchange.com...air-rework-gun
                            Never stop learning
                            Basic LCD TV and Monitor troubleshooting guides.
                            http://www.badcaps.net/forum/showthr...956#post305956

                            Voltage Regulator (LDO) testing:
                            http://www.badcaps.net/forum/showthr...999#post300999

                            Inverter testing using old CFL:
                            http://www.badcaps.net/forum/showthr...er+testing+cfl

                            Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                            http://s807.photobucket.com/user/budm/library/

                            TV Factory reset codes listing:
                            http://www.badcaps.net/forum/showthread.php?t=24809

                            Comment

                            • Maxamus58
                              New Member
                              • Jan 2011
                              • 3

                              #34
                              Re: Acer 42" LCD tv no power or stdby light

                              Thanks budm. I bought this Acer for $150 figuring it to be a relatively simple repair being a power board issue only. The symptoms are that it takes several on/off before the backlight kicks in and a couple more before the tuning circuit settles and I get a clear picture. The input connectors are in poor condition which suggested to me that there was power leakage. After finding this thread and searching for replacement boards I actually found a second TV same model on ebay close by and picked it up for $30. It's connectors are in good nick and it has the same problem but with an extra twist that once up and running but before it is properly warmed it will freeze on garbled screen and emits a full volume banshee scream lol. I'll post back my results.

                              Comment

                              • giannioscar
                                New Member
                                • Sep 2015
                                • 2
                                • cagliari

                                #35
                                Re: Acer 42" LCD tv no power or stdby light

                                ciao scusate ma chiedo per cortesia una informazione ho lo stesso problema con acer ho sostituito tutto tranne dla001d che non trovo ho sostituito il pezzo con l6598d ma come ho appoggiato i piedini e andato in corto potreste aiutarmi grazie ciao

                                Comment

                                • giannioscar
                                  New Member
                                  • Sep 2015
                                  • 2
                                  • cagliari

                                  #36
                                  Re: Acer 42" LCD tv no power or stdby light

                                  Hello sorry but I ask for a courtesy Information I the Same Problem with acer I replaced everything EXCEPT dla001d What I do not find I replaced the piece with L6598D But as I put the legs and went in short you could help me with Hello

                                  Comment

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