Announcement

Collapse
No announcement yet.

Vizio E471VLE Dead

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Vizio E471VLE Dead

    Hello all and happy New Year, I recently acquired this TV from a friend who stated "it's dead". I have had some success in the past restoring so I figured I would give this a go. I'm not an experienced electrician but I am comfortable using a meter and repairing pcb's. My lack of experience translates into difficulty diagnosing which is why I'm here.

    Upon attempted startup the set does nothing but a very short and very faint one time logo flash if even that. Preliminary testing yields the following results.

    Power board fuse = good
    No bloated or leaking caps
    Main cap 168v

    Pins with main board disconnected

    1 - 5.2v = 5.3
    2 - " "
    3 - " "
    4 - gnd
    5 - " "
    6 - " "
    7 - " "
    8 - 12v = 0
    9 - 12v = 0
    10 -12v = 0
    11 - p on/off = 0
    12 - blo/off = 0
    13 - lamp status = 0
    14 - dimming = 0

    Main board connected yields
    Pins 1 through 3 = voltage rapidly fluctuating from 0 to 2.3v
    Pins 4 through 14 = 0

    Can hear a small tick from power board every 1-2 seconds from area to the right of main cap

    Please advise as to what I can do to determine if this is a power or main board problem. Thanks in advance
    Attached Files

    #2
    Re: Vizio E471VLE Dead

    With main board disconnected you can jumper pin 1 to pin 11&12. You should then get your 12vdc and should get backlights. I suspect problem with main board if your standby voltage is fluctuating when connected. Check also your main cap when jumped. It should read around 390vdc
    I assume no responsibility for any stupid suggestions I might post.

    Comment


      #3
      Re: Vizio E471VLE Dead

      Originally posted by dskall View Post
      With main board disconnected you can jumper pin 1 to pin 11&12. You should then get your 12vdc and should get backlights. I suspect problem with main board if your standby voltage is fluctuating when connected. Check also your main cap when jumped. It should read around 390vdc
      Thanks for the reply. Can I jump without a resistor ?

      Comment


        #4
        Re: Vizio E471VLE Dead

        You can use 600ohm to 1k
        I assume no responsibility for any stupid suggestions I might post.

        Comment


          #5
          Re: Vizio E471VLE Dead

          Originally posted by dskall View Post
          You can use 600ohm to 1k
          I'll have to dig one up. I'll get back to you in a little while after completing jump and test. Thanks again

          Comment


            #6
            Re: Vizio E471VLE Dead

            You can also try this:
            Unplug the power to the power supply board, then use hair dryer to heat up the start-up/running caps C160, C161 for about a minute then power up the board with all the cables connected to see if the Standby Voltage will be steady or not.

            Vizio/JVC 0500-0405-1340 Power Supply / Backlight Inverter
            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


              #7
              Re: Vizio E471VLE Dead

              Originally posted by budm View Post
              you can also try this:
              Unplug the power to the power supply board, then use hair dryer to heat up the start-up/running caps c160, c161 for about a minute then power up the board with all the cables connected to see if the standby voltage will be steady or not.

              Vizio/jvc 0500-0405-1340 power supply / backlight inverter
              10-4

              Comment


                #8
                Re: Vizio E471VLE Dead

                Originally posted by dskall View Post
                With main board disconnected you can jumper pin 1 to pin 11&12. You should then get your 12vdc and should get backlights. I suspect problem with main board if your standby voltage is fluctuating when connected. Check also your main cap when jumped. It should read around 390vdc
                Ok jumped pins 1, 11, 12 and have backlights. At this point all voltages across cn201 are correct and stable. Main cap cap value is 383v.

                Going to try Bud's suggestion real quick and will post results


                Thanks again for assistance.

                Comment


                  #9
                  Re: Vizio E471VLE Dead

                  Originally posted by budm View Post
                  You can also try this:
                  Unplug the power to the power supply board, then use hair dryer to heat up the start-up/running caps C160, C161 for about a minute then power up the board with all the cables connected to see if the Standby Voltage will be steady or not.

                  Vizio/JVC 0500-0405-1340 Power Supply / Backlight Inverter
                  Tested and results are the same. Voltages fluctuating rapidly 0-3v

                  Comment


                    #10
                    Re: Vizio E471VLE Dead

                    So where do I go from here ? Do these results indicate a main board failure ?

                    Comment


                      #11
                      Re: Vizio E471VLE Dead

                      I would say you have bad regulator or something on main board loading down standby voltage
                      I assume no responsibility for any stupid suggestions I might post.

                      Comment


                        #12
                        Re: Vizio E471VLE Dead

                        Originally posted by dskall View Post
                        I would say you have bad regulator or something on main board loading down standby voltage
                        I am having trouble finding the original and revised main board available for purchase. Is it feasible determine exactly what's malfunctioning on the board or is this a scrap ?

                        Comment


                          #13
                          Re: Vizio E471VLE Dead

                          Try disconnecting the IR board from the main board to see if the STBY will be steady.
                          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


                            #14
                            Re: Vizio E471VLE Dead

                            Originally posted by budm View Post
                            Try disconnecting the IR board from the main board to see if the STBY will be steady.
                            Will when I get back to the house. Thanks

                            Comment


                              #15
                              Re: Vizio E471VLE Dead

                              Originally posted by budm View Post
                              Try disconnecting the IR board from the main board to see if the STBY will be steady.
                              Same result. Does this pinpoint the main board as the issue ? Is there any way to determine what component on the board is failing ? Looks like servicing the board might be the only hope as I cannot find a replacement.

                              Comment


                                #16
                                Re: Vizio E471VLE Dead

                                At this point, something on the main board is drawing too much current so the STBY 5V goes into shutdown/restart cycle.
                                May be check the resistance between GND and the 5VSTBY pin with all the board connected to see if it may show really low resistance or not.
                                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


                                  #17
                                  Re: Vizio E471VLE Dead

                                  Originally posted by budm View Post
                                  At this point, something on the main board is drawing too much current so the STBY 5V goes into shutdown/restart cycle.
                                  May be check the resistance between GND and the 5VSTBY pin with all the board connected to see if it may show really low resistance or not.
                                  Ok I will check this in the morning. Thanks

                                  Comment


                                    #18
                                    Re: Vizio E471VLE Dead

                                    Originally posted by budm View Post
                                    At this point, something on the main board is drawing too much current so the STBY 5V goes into shutdown/restart cycle.
                                    May be check the resistance between GND and the 5VSTBY pin with all the board connected to see if it may show really low resistance or not.
                                    I could not get an accurate reading. Resistance jumps from 1 to all over the place.

                                    Comment


                                      #19
                                      Re: Vizio E471VLE Dead

                                      You are checking resistance with power off
                                      I assume no responsibility for any stupid suggestions I might post.

                                      Comment


                                        #20
                                        Re: Vizio E471VLE Dead

                                        TV is unplugged from the AC outlet when checking the resistance.
                                        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

                                        Working...