42PFL7406 No Power

Collapse
X
Collapse
+ More Options
Posts
 
  • Time
  • Show
Clear All
new posts
  • trunks81
    Badcaps Veteran
    • May 2020
    • 265
    • Nederland

    #21
    Re: 42PFL7406 No Power

    Hello

    this are the part numbers of those parts

    Q601 = K3530
    Q801 = Cannot read
    Q701A = K4A60DA
    Q701B = K4A60DA
    IC601 = 2QS02G
    IC801 = 1608B
    IC701 = DDA009
    IC901 = DDA010
    IC902 = S101202D
    Attached Files
    Last edited by trunks81; 07-18-2020, 12:51 PM.

    Comment

    • trunks81
      Badcaps Veteran
      • May 2020
      • 265
      • Nederland

      #22
      Re: 42PFL7406 No Power

      Originally posted by thommyX
      IC901 is a DDA010 and IC902 is an ST9S101 / IN1M101.
      If the brown out is faulty, you have fluctuating tensions.


      LG Thomas
      Changed both IC and problem is still the same

      Comment

      • dick_barton
        Badcaps Legend
        • Aug 2015
        • 6642
        • Wales

        #23
        Re: 42PFL7406 No Power

        What voltage do you have across C908 and also at the FB pin 2 of IC901 and are they steady
        Last edited by dick_barton; 08-12-2020, 09:38 AM.
        Willing to help but I'm no expert.

        Comment

        • trunks81
          Badcaps Veteran
          • May 2020
          • 265
          • Nederland

          #24
          Re: 42PFL7406 No Power

          On pin 2 of IC902 iam getting 0V to 0.23V
          On C908 iam getting 13v to 19v
          Also i found that ZD904 is low in diodemode 0.0029 in both directions
          When soldered out iam getting 0.69 and reverse 2,7

          Comment

          • dick_barton
            Badcaps Legend
            • Aug 2015
            • 6642
            • Wales

            #25
            Re: 42PFL7406 No Power

            It looks like your pfc circuit is switching on when the voltage across C908 reaches 18V and then stopping when the voltage falls which would be the reason your secondary voltages are oscillating.

            It does look like a short but is it the zener or R902 since that is across ZD904. You could lift one end of ZD904 to test it or it could be a short on the IC pin to ground.

            CS is the current source pin which would have a low value resistor (R902) attached to it and hot ground.
            Last edited by dick_barton; 08-12-2020, 12:35 PM.
            Willing to help but I'm no expert.

            Comment

            • trunks81
              Badcaps Veteran
              • May 2020
              • 265
              • Nederland

              #26
              Re: 42PFL7406 No Power

              When ZD904 soldered out iam getting 3ohm in R902 also when soldered out it is 3ohm marking on the resistor is 47Y
              Attached Files
              Last edited by trunks81; 08-12-2020, 12:59 PM.

              Comment

              • dick_barton
                Badcaps Legend
                • Aug 2015
                • 6642
                • Wales

                #27
                Re: 42PFL7406 No Power

                47Y is 47 ohms according to http://kiloohm.info/eia96-resistor/47Y

                Are you certain it's 47Y since that seems to be a high value resistor as a source resistor.
                Last edited by dick_barton; 08-12-2020, 01:01 PM.
                Willing to help but I'm no expert.

                Comment

                • trunks81
                  Badcaps Veteran
                  • May 2020
                  • 265
                  • Nederland

                  #28
                  Re: 42PFL7406 No Power

                  iam confused.. according to the same site it is an 3.01 ohm
                  Please see picture in previous post for resistor

                  Comment

                  • dick_barton
                    Badcaps Legend
                    • Aug 2015
                    • 6642
                    • Wales

                    #29
                    Re: 42PFL7406 No Power

                    I stand corrected it is 3.01 ohms.
                    Willing to help but I'm no expert.

                    Comment

                    • budm
                      Badcaps Legend
                      • Feb 2010
                      • 40746
                      • USA

                      #30
                      Re: 42PFL7406 No Power

                      I forgot about this thread, too busy with the 37" & 47" threads.
                      So at this point if you run the power supply board by itself and force it on, is the PFC boost Voltage staying on?
                      Last edited by budm; 08-12-2020, 03:52 PM.
                      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

                      • trunks81
                        Badcaps Veteran
                        • May 2020
                        • 265
                        • Nederland

                        #31
                        Re: 42PFL7406 No Power

                        I connected pin 1 and 2 on 1M95 (CN4) with an 1K Resistor
                        And on

                        C800 = 313VDC
                        C908 = 17.21VDC

                        Comment

                        • budm
                          Badcaps Legend
                          • Feb 2010
                          • 40746
                          • USA

                          #32
                          Re: 42PFL7406 No Power

                          Originally posted by trunks81
                          I connected pin 1 and 2 on 1M95 (CN4) with an 1K Resistor
                          And on

                          C800 = 313VDC
                          C908 = 17.21VDC
                          The PS-ON (STANDBY) for this Philips power supply is Active Low, so you need to Ground pin 2 (STANDBY) of CN4 to Ground pin 3, 4, 8, or 14 using 100 Ohms resistor or so to turn on the power supply.
                          Attached Files
                          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

                          • trunks81
                            Badcaps Veteran
                            • May 2020
                            • 265
                            • Nederland

                            #33
                            Re: 42PFL7406 No Power

                            does it really need to be an 100ohm ? because i dont have it right now

                            When stubborn using an 1K iam getting

                            C800=407
                            C908=17.30
                            Last edited by trunks81; 08-13-2020, 04:45 AM.

                            Comment

                            • dick_barton
                              Badcaps Legend
                              • Aug 2015
                              • 6642
                              • Wales

                              #34
                              Re: 42PFL7406 No Power

                              What are the values of R959 & R960.

                              For standby: - do you have a couple of resistors you could put in parallel. e.g. 2 x 1K in parallel = 500 ohms
                              Last edited by dick_barton; 08-13-2020, 04:45 AM.
                              Willing to help but I'm no expert.

                              Comment

                              • trunks81
                                Badcaps Veteran
                                • May 2020
                                • 265
                                • Nederland

                                #35
                                Re: 42PFL7406 No Power

                                Both resistor measure oke, measured them in circuit

                                R959 = 01D = 100kohm
                                R960 = 69B = 5.11kohm
                                Attached Files

                                Comment

                                • dick_barton
                                  Badcaps Legend
                                  • Aug 2015
                                  • 6642
                                  • Wales

                                  #36
                                  Re: 42PFL7406 No Power

                                  Looking at those values I think it's safe enough to short standby to ground.
                                  Willing to help but I'm no expert.

                                  Comment

                                  • budm
                                    Badcaps Legend
                                    • Feb 2010
                                    • 40746
                                    • USA

                                    #37
                                    Re: 42PFL7406 No Power

                                    I suggest using resistor just in case OP ground the wrong pin on the connector by mistake if he jumps directly, OP can jump STANDBY pin to ground directly with no problem, I am just afraid that OP will make mistake and ground the wrong pin.
                                    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

                                    • trunks81
                                      Badcaps Veteran
                                      • May 2020
                                      • 265
                                      • Nederland

                                      #38
                                      Re: 42PFL7406 No Power

                                      ive used an 1K instead of 100ohm.. and that seems to work also

                                      Comment

                                      • budm
                                        Badcaps Legend
                                        • Feb 2010
                                        • 40746
                                        • USA

                                        #39
                                        Re: 42PFL7406 No Power

                                        So is the PFC Boosted Voltage present then?
                                        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

                                        • trunks81
                                          Badcaps Veteran
                                          • May 2020
                                          • 265
                                          • Nederland

                                          #40
                                          Re: 42PFL7406 No Power

                                          Originally posted by trunks81
                                          does it really need to be an 100ohm ? because i dont have it right now

                                          When stubborn using an 1K iam getting

                                          C800=407VDC
                                          C908=17.30VDC
                                          This is what iam getting with 1K present

                                          Comment

                                          Related Topics

                                          Collapse

                                          • Tynan Dill
                                            Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?
                                            by Tynan Dill
                                            I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.

                                            Upon bringing it home and plugging it up, it showed a standby light.

                                            I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.

                                            The screen seems to blackout and stay black, but with a flashlight I can see the display.

                                            With my Playstation 4 connected via HDMI, and running a game I can hear sound.

                                            Assuming...
                                            11-22-2024, 01:46 PM
                                          • PantherDave
                                            Microsoft Surface Pro (5th gen) model 1796 - no power
                                            by PantherDave
                                            Hi all!

                                            I'm trying to troubleshoot a Microsoft Surface Pro (5th gen) model 1796 that won't power on. Motherboard model is M1007506-015. My priority is retrieving data, but the SSD is integrated so it looks like if I can't repair it it'll need to go to a data recovery company. I've done a little basic board repair before, but nothing this advanced until now. So please forgive my ignorance in advance. 😅

                                            I found the boardview for this laptop in the forums here, and am able to open it on my PC with FlexBV.
                                            https://www.badcaps.net/forum/troubl...-hardware-devi...
                                            05-29-2024, 02:01 PM
                                          • GLISIT
                                            Asus Probook P5440UF-XB74 power issue
                                            by GLISIT
                                            Hi all,

                                            TL;DR - this laptop is driving me nuts with the oddball power-related behaviors. Appreciate any insight you can provide!


                                            I'm experiencing a power issue on an Asus Probook P5440UF-XB74. Although I've worked with electronics and computers for decades, this is my first attempt at getting into motherboard-level component troubleshooting. Any help the community can provide is greatly appreciated!

                                            A few weeks ago I was using the laptop (on battery power) for a Zoom meeting. The battery was running very low (long meeting) but I wasn't worried about...
                                            01-16-2025, 02:29 PM
                                          • sam_sam_sam
                                            Desoldering gun station modified to use a 18 volt @ 20 amp switching power supply
                                            by sam_sam_sam
                                            I have wanting to do this project for quite sometime now and I finally found a switching power supply that will work on this desoldering gun station ZD-915 that the original switching power supply took a shit and just was not worth trying to fix it because this switching power is not quite big enough to handle the heater element and the vacuum pump

                                            One note when I tested the switching power supply and the voltage control board I noticed that this desoldering gun heat up much faster than the original switching power supply which I was really surprised by to the point that I might buy...
                                            03-31-2024, 02:12 PM
                                          • Document Archive
                                            HP Pavilion Power Pavilion Power 15-cb009nl Notebook 15 Specification for Upgrade or Repair
                                            by Document Archive
                                            This specification for the HP Pavilion Power Pavilion Power 15-cb009nl Notebook can be useful for upgrading or repairing a laptop that is not working. As a community we are working through our specifications to add valuable data like the Pavilion Power 15-cb009nl boardview and Pavilion Power 15-cb009nl schematic. Our users have donated over 1 million documents which are being added to the site. This page will be updated soon with additional information. Alternatively you can request additional help from our users directly on the relevant badcaps forum. Please note that we offer no warranties that...
                                            09-06-2024, 05:59 AM
                                          • Loading...
                                          • No more items.
                                          Working...