Thank you to the guys at HEGE supporting Badcaps [ HEGE ] [ HEGE DEX Chart ]

Announcement

Collapse
No announcement yet.

BenQ FP71G+S (No, it's not just the backlight)

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
    #1

    BenQ FP71G+S (No, it's not just the backlight)

    No, it's NOT just the backlight this time. When I turn it on, it says on for about 1 or 2 seconds and powers off again completely (the power light also turns off). Upon opening it I noticed what looks like some heat discolouration around the bottom left corner of the first pic. The transistor on the other side (IC701) doesn't look fried, although I can't read the markings on it. It looks like there is a coat of flux on it, which I cleaned off. Markings are L117 33 KDF6520 (
    hard to tell. Could also be KOF6520). The caps are all Elite, except for a few small 100uF 25V Jamicons and two light green 1000uF 10V Lelons.

    What do you guys think? Caps? or something else?
    Attached Files
    I love putting bad caps and flat batteries in fire and watching them explode!!

    No wonder it doesn't work! You installed the jumper wires backwards

    Main PC: Core i7 3770K 3.5GHz, Gigabyte GA-Z77M-D3H-MVP, 8GB Kingston HyperX DDR3 1600, 240GB Intel 335 Series SSD, 750GB WD HDD, Sony Optiarc DVD RW, Palit nVidia GTX660 Ti, CoolerMaster N200 Case, Delta DPS-600MB 600W PSU, Hauppauge TV Tuner, Windows 7 Home Premium

    Office PC: HP ProLiant ML150 G3, 2x Xeon E5335 2GHz, 4GB DDR2 RAM, 120GB Intel 530 SSD, 2x 250GB HDD, 2x 450GB 15K SAS HDD in RAID 1, 1x 2TB HDD, nVidia 8400GS, Delta DPS-650BB 650W PSU, Windows 7 Pro
    Tags: None
    #2
    Re: BenQ FP71G+S (No, it's not just the backlight)

    Have you tried testing for shorts on the part that got hot?

    Comment

      #3
      Re: BenQ FP71G+S (No, it's not just the backlight)

      I bet the L117 33 is a voltage regulator that outputs 3.3V DC. I only say this because of my recent finds with A1117 voltage regulators in my Daytek thread.

      On both my FP71G+, I have the same discoloration from the same IC701 location.

      Check (since you didn't say you did or not)

      1) PF801. On mine, it it shorted.
      2) Check c5707 transistors. I have 2 bad on mine.
      3) Check FU9024N.

      Originally posted by c_hegge
      The transistor on the other side (IC701) doesn't look fried, although I can't read the markings on it. It looks like there is a coat of flux on it, which I cleaned off. Markings are L117 33 KDF6520 (hard to tell. Could also be KOF6520).
      --- begin sig file ---

      If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

      We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

      Please do not post inline and offsite as they slow down the loading of pages.

      --- end sig file ---

      Comment

        #4
        Re: BenQ FP71G+S (No, it's not just the backlight)

        Originally posted by el3ctroded
        Have you tried testing for shorts on the part that got hot?
        I did. it doesn't seem to be shorted.

        Originally posted by retiredcaps
        1) PF801. On mine, it it shorted.
        2) Check c5707 transistors. I have 2 bad on mine.
        3) Check FU9024N.
        1. Aren't fuses supposed to be shorted and only open when they blow?
        2. Thanks. Will do.
        3. Assuming you mean transistors Q812 and Q805, neither are shorted on this monitor
        I love putting bad caps and flat batteries in fire and watching them explode!!

        No wonder it doesn't work! You installed the jumper wires backwards

        Main PC: Core i7 3770K 3.5GHz, Gigabyte GA-Z77M-D3H-MVP, 8GB Kingston HyperX DDR3 1600, 240GB Intel 335 Series SSD, 750GB WD HDD, Sony Optiarc DVD RW, Palit nVidia GTX660 Ti, CoolerMaster N200 Case, Delta DPS-600MB 600W PSU, Hauppauge TV Tuner, Windows 7 Home Premium

        Office PC: HP ProLiant ML150 G3, 2x Xeon E5335 2GHz, 4GB DDR2 RAM, 120GB Intel 530 SSD, 2x 250GB HDD, 2x 450GB 15K SAS HDD in RAID 1, 1x 2TB HDD, nVidia 8400GS, Delta DPS-650BB 650W PSU, Windows 7 Pro

        Comment

          #5
          Re: BenQ FP71G+S (No, it's not just the backlight)

          I agree with retiredcaps, that's a 3.3 volt regulator.

          The fact that it does a total shutdown is significant. The first step would be to check the 5.5, 3.3, and 12 volts (if present) on the cable to the logic card. If they are still present and stable, the problem is PROBABLY on the logic card. If they disappear, look at the power supply board.

          It goes without saying - replacing those Elite caps would be a very good idea. Also, check any voltage regulators on the logic card.

          PlainBill
          For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

          Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

          Comment

            #6
            Re: BenQ FP71G+S (No, it's not just the backlight)

            Yes, sorry, I meant open. I should have just wrote, make sure the picofuse is 0.03ohms or less.

            Originally posted by c_hegge
            1. Aren't fuses supposed to be shorted and only open when they blow?
            --- begin sig file ---

            If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

            We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

            Please do not post inline and offsite as they slow down the loading of pages.

            --- end sig file ---

            Comment

              #7
              Re: BenQ FP71G+S (No, it's not just the backlight)

              Retiredcaps, I checked the pico fuse and it seems fine

              PlainBill, Do you know what voltages to expect on which pins? There is no cable for logic board, it plugs straight in to the power supply.
              I love putting bad caps and flat batteries in fire and watching them explode!!

              No wonder it doesn't work! You installed the jumper wires backwards

              Main PC: Core i7 3770K 3.5GHz, Gigabyte GA-Z77M-D3H-MVP, 8GB Kingston HyperX DDR3 1600, 240GB Intel 335 Series SSD, 750GB WD HDD, Sony Optiarc DVD RW, Palit nVidia GTX660 Ti, CoolerMaster N200 Case, Delta DPS-600MB 600W PSU, Hauppauge TV Tuner, Windows 7 Home Premium

              Office PC: HP ProLiant ML150 G3, 2x Xeon E5335 2GHz, 4GB DDR2 RAM, 120GB Intel 530 SSD, 2x 250GB HDD, 2x 450GB 15K SAS HDD in RAID 1, 1x 2TB HDD, nVidia 8400GS, Delta DPS-650BB 650W PSU, Windows 7 Pro

              Comment

                #8
                Re: BenQ FP71G+S (No, it's not just the backlight)

                Originally posted by c_hegge
                Retiredcaps, I checked the pico fuse and it seems fine

                PlainBill, Do you know what voltages to expect on which pins? There is no cable for logic board, it plugs straight in to the power supply.
                Look at the back of the board. There are 12 pins. 4 of them are obviously ground, two of them are not used. Two others are connected to thin traces; they are the control lines for the inverter. That leaves you with two sets of two. You had better be able to take it from there.

                PlainBill
                For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                Comment

                  #9
                  Re: BenQ FP71G+S (No, it's not just the backlight)

                  Here is what I have on mine. I only measured the "even" pins because the "odd" numbered pins are hard to reach with the probes.

                  pin 2: 0.00V
                  pin 4: 0.00V
                  pin 6: 0.00V
                  pin 8: 5.23V
                  pin 10: 3.29V
                  pin 12: 3.25V


                  Originally posted by c_hegge
                  PlainBill, Do you know what voltages to expect on which pins?
                  --- begin sig file ---

                  If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                  We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                  Please do not post inline and offsite as they slow down the loading of pages.

                  --- end sig file ---

                  Comment

                    #10
                    Re: BenQ FP71G+S (No, it's not just the backlight)

                    Voltages are there, even after the shut down. Also, after it shuts down, you can power it back on immediately after, without unplugging the AC, but it will just shut off again. Looking like the logic board at this point.
                    I love putting bad caps and flat batteries in fire and watching them explode!!

                    No wonder it doesn't work! You installed the jumper wires backwards

                    Main PC: Core i7 3770K 3.5GHz, Gigabyte GA-Z77M-D3H-MVP, 8GB Kingston HyperX DDR3 1600, 240GB Intel 335 Series SSD, 750GB WD HDD, Sony Optiarc DVD RW, Palit nVidia GTX660 Ti, CoolerMaster N200 Case, Delta DPS-600MB 600W PSU, Hauppauge TV Tuner, Windows 7 Home Premium

                    Office PC: HP ProLiant ML150 G3, 2x Xeon E5335 2GHz, 4GB DDR2 RAM, 120GB Intel 530 SSD, 2x 250GB HDD, 2x 450GB 15K SAS HDD in RAID 1, 1x 2TB HDD, nVidia 8400GS, Delta DPS-650BB 650W PSU, Windows 7 Pro

                    Comment

                      #11
                      Re: BenQ FP71G+S (No, it's not just the backlight)

                      Originally posted by c_hegge
                      Voltages are there, even after the shut down. Also, after it shuts down, you can power it back on immediately after, without unplugging the AC, but it will just shut off again. Looking like the logic board at this point.
                      That's what I would expect. I would carefully check the voltage regulators on the logic board.

                      PlainBill
                      For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                      Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                      Comment

                        #12
                        Re: BenQ FP71G+S (No, it's not just the backlight)

                        If it helps, on mine, I only see one obvious voltage regulator which is a 950T65. On pin 1, I get 3.3V DC and pin 3, I get 2.5V DC. pin 2 is GND.

                        Originally posted by PlainBill
                        I would carefully check the voltage regulators on the logic board.
                        PlainBill
                        --- begin sig file ---

                        If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                        We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                        Please do not post inline and offsite as they slow down the loading of pages.

                        --- end sig file ---

                        Comment

                          #13
                          Re: BenQ FP71G+S (No, it's not just the backlight)

                          I did a resistance test between the pins. It doesn't seem to be shorted. I got another monitor cheap, so I'm not all that worried over it anymore. I'll try re-capping the Power supply with pannies. If it doesn't help, I'll get rid of it.
                          I love putting bad caps and flat batteries in fire and watching them explode!!

                          No wonder it doesn't work! You installed the jumper wires backwards

                          Main PC: Core i7 3770K 3.5GHz, Gigabyte GA-Z77M-D3H-MVP, 8GB Kingston HyperX DDR3 1600, 240GB Intel 335 Series SSD, 750GB WD HDD, Sony Optiarc DVD RW, Palit nVidia GTX660 Ti, CoolerMaster N200 Case, Delta DPS-600MB 600W PSU, Hauppauge TV Tuner, Windows 7 Home Premium

                          Office PC: HP ProLiant ML150 G3, 2x Xeon E5335 2GHz, 4GB DDR2 RAM, 120GB Intel 530 SSD, 2x 250GB HDD, 2x 450GB 15K SAS HDD in RAID 1, 1x 2TB HDD, nVidia 8400GS, Delta DPS-650BB 650W PSU, Windows 7 Pro

                          Comment

                            #14
                            Re: BenQ FP71G+S (No, it's not just the backlight)

                            Before you recap, check the voltage on the regulator. I'm not 100% sure, but a resistance test may not be sufficient.

                            It may not be shorted, but it may not put out 2.5V DC.

                            Originally posted by c_hegge
                            I did a resistance test between the pins. It doesn't seem to be shorted.
                            --- begin sig file ---

                            If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                            We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                            Please do not post inline and offsite as they slow down the loading of pages.

                            --- end sig file ---

                            Comment

                              #15
                              Re: BenQ FP71G+S (No, it's not just the backlight)

                              Originally posted by c_hegge View Post
                              No, it's NOT just the backlight this time. When I turn it on, it says on for about 1 or 2 seconds and powers off again completely (the power light also turns off). Upon opening it I noticed what looks like some heat discolouration around the bottom left corner of the first pic. The transistor on the other side (IC701) doesn't look fried, although I can't read the markings on it. It looks like there is a coat of flux on it, which I cleaned off. Markings are L117 33 KDF6520 (
                              hard to tell. Could also be KOF6520). The caps are all Elite, except for a few small 100uF 25V Jamicons and two light green 1000uF 10V Lelons.

                              What do you guys think? Caps? or something else?
                              Damn! It looks like the same card I have in my hands right now! I'll get through the problem with all your infos and input. I'll come back to give you what happened or if I'm still searching!

                              Great forum! Great people!!

                              Cheers!!

                              Jeff

                              Comment

                                #16
                                Re: BenQ FP71G+S (No, it's not just the backlight)

                                Jeez, forgot to ask, how do I check the backlights?

                                Thanks in advance!

                                Jeff

                                Comment

                                  #17
                                  Re: BenQ FP71G+S (No, it's not just the backlight)

                                  Change the transistors of the backlights, 4+2.
                                  Even if they seems good with the diode test they probably have ad higher hfe draining more current and causing the logic to shutdown.
                                  You can find a kit on ebay.

                                  Comment

                                  Previous template Next
                                  Working...
                                  X