Announcement

Collapse
No announcement yet.

Samsung 2493HM issue

Collapse
X
Collapse
 
  • Page of 3
  • Filter
  • Time
  • Show
Clear All
new posts
Previous 1 2 3 template Next
    #21
    Re: Samsung 2493HM issue

    Originally posted by werthles View Post
    Now i just need to find out what kind of fuse they are.
    It is hard to tell from the angle of the pictures, but they (the fuse values) are usually written write on the board.
    --- 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

      #22
      Re: Samsung 2493HM issue

      Yeah, i figured out what kind they were. I checked the bridge rectifier and its good. I should have the fuses in a week or so. Ill post pics of my setup for testing out those chips when i get the fuses.

      Comment

        #23
        Re: Samsung 2493HM issue

        Ok, i replaced the two fuses on the power board and i am back where i started. Meaning, i get a solid blue led and no picture. Im posting two pics of the opposite sides of the semi-assembled boards. The metal shielding is blocking access to the pins on those chips that i need to test. Is there a possibility of not connecting some of the components to do the test or will that yield inconclusive results?
        Attached Files
        Last edited by werthles; 02-23-2011, 03:16 AM. Reason: forgot the pics. oops

        Comment

          #24
          Re: Samsung 2493HM issue

          Leave the power boad face down. Unscrew the logic card and turn it face up (leave screws out). Put a piece of cardboard underneath the logic board so it is not touching the metal shield.

          Leave the connections in place.

          Now measure the voltage regulators on the logic card. You can still use a screw hole (GND) for the black probe.
          --- 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

            #25
            Re: Samsung 2493HM issue

            Ok, here is my problem. As you can see from the pics, this is the only way i can set it up where i got the wires hooked up (except the speakers, which i hope is ok for the test). Can i still use the screw holes on the logic board as a ground?
            Attached Files

            Comment

              #26
              Re: Samsung 2493HM issue

              you can use the screw holes or the metal shields of the VGA, DVI or HDMI connectors.
              i usually stick the negative lead of my DMM into the holes intended to fasten the VGA or DVI cable to the socket.

              oh and you might wanna get the keypad out of the casing and connect it up.. otherwise you won't be able to turn it on (most monitors stay in off-mode when the button board isn't connected)

              edit: in theory you should be able to use the whole metal cage as ground too. It should be grounded through the various screws of the PSU board and others.
              Last edited by Scenic; 02-24-2011, 01:39 AM.

              Comment

                #27
                Re: Samsung 2493HM issue

                Ok, i tested all the pins on those chips and i get no reading whatsoever. I used the metal shielding as the ground. Am i supposed to get at least some sort of reading?

                Comment

                  #28
                  Re: Samsung 2493HM issue

                  Originally posted by werthles View Post
                  Am i supposed to get at least some sort of reading?
                  Is the power LED on? If yes, you should defintely get a reading with your multimeter set on 20V DC.
                  --- 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

                    #29
                    Re: Samsung 2493HM issue

                    Ok, sorry for the delay. I forgot to hook up the control panel. Thats why i didnt get any readings at first. On the red circled chip i got 5.22, 0, 5.22 on the three pins starting from the top in the image. On the yellow circled chip i got 2.52, 0, 3.31 on the three pins starting from the top in the image.

                    Comment

                      #30
                      Re: Samsung 2493HM issue

                      Originally posted by werthles View Post
                      On the red circled chip i got 5.22, 0, 5.22 on the three pins starting from the top in the image. On the yellow circled chip i got 2.52, 0, 3.31 on the three pins starting from the top in the image.
                      Hmm, can you recheck the voltages for the red circled chip again? The readings you have provided don't seem right.

                      The yellow readings looks correct.
                      --- 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

                        #31
                        Re: Samsung 2493HM issue

                        I just checked again, same results.

                        Comment

                          #32
                          Re: Samsung 2493HM issue

                          Originally posted by werthles View Post
                          I just checked again, same results.
                          1) Okay, with power off and lcd unplugged, put your multimeter on 200 ohms (if manual), and measure the red circled component to see if it is shorted.

                          Measure the resistance between pin 1-2, 1-3, and 2-3. List all the ohms measurements. A reading of 30 ohms or less suggests the voltage regulator is shorted.

                          2) Can you post a clear focused picture of just the red circled component? Clear enough that we can see/read the part number.

                          3) What is the board designation for this component? That is, what is the PCB marking for this component? Is it something like U102?
                          --- 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

                            #33
                            Re: Samsung 2493HM issue

                            I was unable to get any reading under 200 ohms. I set it to 20k ohms and i got the following readings:

                            1-2: 3.15
                            1-3: 2.19
                            2-3: 10 (and constantly rising)

                            Ill have to look up on how to get my camera to be able to focus on those chips

                            Comment

                              #34
                              Re: Samsung 2493HM issue

                              Originally posted by werthles View Post
                              I was unable to get any reading under 200 ohms. I set it to 20k ohms and i got the following readings:

                              1-2: 3.15
                              1-3: 2.19
                              2-3: 10 (and constantly rising)
                              Just to clarify your multimeter's operation ...

                              If you have a manual ranging multimeter, set it to 200 (two hundred) ohms. Touch the black and red probe together. It should read 0.3 or 0.4 ohms. If it is higher than 1.0 ohm, there is something wrong with your multimeter.

                              If your multimeter reads "1" or "OL", it means the measurement is outside your chosen range. Don't confuse "1" on the left hand side of this display with 1.0 on the right hand side. The first means out of range and the second means 1.0 unit of your measurement.
                              --- 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

                                #35
                                Re: Samsung 2493HM issue

                                Im just gonna replace that one capacitor that i snagged from another system and see if that does anything.

                                Comment

                                  #36
                                  Re: Samsung 2493HM issue

                                  I just tested my multimeter, it works fine. I still could not get a reading off of those chips when the multimeter was set to 200 ohms. I only saw result when i switched it to 20k ohms.

                                  Comment

                                    #37
                                    Re: Samsung 2493HM issue

                                    I have a sense that I'm not getting the message through.

                                    Setting your multimeter on 200 ohms and getting a reading of "1" on the left hand side IS a reading. It implies the reading is > 200 ohms. That implies the voltage regulator is not shorted.

                                    However, the DC voltage readings suggests it is "failing high". Normally a voltage regulator takes a voltage in (say 5V DC) and outputs something lower like 3.3V or 1.8V DC depending on the regulator.

                                    With the part number you gave (6P741), I cannot find a datasheet to verify what should be the correct voltage. That is why I asked for a clear close up picture of the component.
                                    --- 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

                                      #38
                                      Re: Samsung 2493HM issue

                                      Sorry about that. I have been trying to figure out why i cant get my camera to get a close up of that specific chip. I will play around with it some more.

                                      Comment

                                        #39
                                        Re: Samsung 2493HM issue

                                        I tried to get my camera to focus on that chip and to no avail. Ill note what numbers i see around it. Maybe IC304 is its part number.

                                        Comment

                                          #40
                                          Re: Samsung 2493HM issue

                                          The 6P741 appears to be too small for a voltage regulator. Probably a special function chip.

                                          Comment

                                          Previous 1 2 3 template Next
                                          Working...