Announcement

Collapse
No announcement yet.

User Profile

Collapse

Profile Sidebar

Collapse
Avatar
lotr
Member
Last Activity: 02-03-2014, 10:07 AM
Joined: 12-12-2011
Location:
  •  
  • Filter
  • Time
  • Show
  • Source
Clear All
new posts
  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    So I replaced the resistor, checked it before and after installing, plugged in the power cord and the power led comes on and then a few seconds later the Philips logo showed up on the screen and the tv WORKS!!!!

    Thanks PlainBill for all the help and hopefully this helps out other people with same problem.

    If you are going to be in Toronto area let me know and I'll buy you a beer.
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    Ok, I took out the resistor and still no reading so definitely will need replacing.

    Schematics call for 470K 1/4W, should this be okay or should I use another value.
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    I checked the resistance of all 4 resistors.

    R603 could not get a reading
    R604 474K
    R605 472K
    R606 470K

    I also checked the resistance of the after pin to the before pin of each resistor and got a reading of 0 which usually means continuity so they must be all connected.

    Is the problem R603 or do I have to measure it out of circuit?
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    I would like to say thanks for being patient as I only know the basics and am trying to learn as we go.

    I checked the solder joints and they all look okay and there is no movement for any of the resistors.

    There is no R609 installed on the board so I used R611 as the live ground point (if I read the schematics correctly) where I placed the black test lead.

    Now when I usually check to see where one component is connecting to another component I check the trace lines, however there is no trace lines on...
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    I removed C603 from the board but did not get any resistance reading with the DMM.

    I am not sure what you mean by the voltage at the junctions between two resistors. I took readings with the test leads before and after each of the resistors (R603, R604, R605, R606). I took these readings with C603 back on the board.

    R603 140V
    R604 0
    R605 0
    R606 0

    When I went to check the voltage on R603 there was a noise for about 1 sec and then there was a click sound and another click 1 sec later...
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    Attached pic to help with explanation.

    Q601 with ground on pin 3 of T601.

    Pin 1 (on 200M setting on DMM), 2.8
    Pin 2 (on 200V setting on DMM), 169
    Pin 3, 0

    Q602 with ground on pin 3 of T601

    Pin 1, 0
    Pin 2 (on 200M setting on DMM), 8.6
    Pin 3, 0

    IC601 with ground on pin 3 of T601

    Pin 3, 0
    Pin 4 (on 200M setting on DMM), 13.6

    IC601 with ground on pin 12 of T601 (I am assuming that the pin layout is like IC chips...
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    I don't know much about transistors so I did some reading and hopefully I measured it correctly.

    I have number the pins in the attachment to help with this explanation.

    On Q601, I had the red test lead on pin 3 and moved the black test lead from pin 2 to 1, using the diode check setting on DMM and measured readings only one way. The 200 ohms setting I got the momentary reading like the others from before.

    On Q602, I had the black test lead on pin 2 and moved the red test lead from pin 1 to 3, using...
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    Appreciate the help even on football Sunday.

    I have not checked the voltages yet because I can not flip the board because there are cables on two different sides of the board and because of the tightness of the heatsink and transformer I can not get the test lead in without touching something. So I am going to buy some test leads with a mini grabber and then check the voltages.

    I did check the diodes and there are some interesting results.

    (Note: two diodes on the schematics were not installed on the...
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    Yes, I am interested (as long as your not suggesting I use my hands to check voltages ).

    If you can provide instructions on what to do I do not believe I will have problems.

    Thanks.
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    Yes, I used 820K 1/4W for both R1217 and R1218 and used 390K 1/4W for R1219.

    I checked the resistors with a meter before using them and the connections are good on the board.
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power

    I changed all three resistors, no luck.

    Still the same problem, clicking can be heard when tv is plugged and unplugged otherwise nothing, no power led no other sounds.

    Any other suggestions on what I can check to see why there is no power going from the inverter/power board to the signal board?
    See more | Go to post

    Leave a comment:

  • lotr
    replied to Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources
    Re: Philips 42PFL3704D LCD no power



    I checked the service manual and it says:

    R1217 820K 1/4W
    R1218 820K 1/4W
    R1219 820K 1/4W

    Should I change just R1219 to 390K?



    I checked the fuse and it is giving a resistance of 0.7 ohms which I believe reading in one of the threads was an ok value.

    I checked the input voltage from the power chord on the circuit board at CN1601 and there is 120V AC coming in.

    I could not find where to check for the standby voltage but I did...
    See more | Go to post

    Leave a comment:

  • lotr
    started a topic Philips 42PFL3704D LCD no power
    in Troubleshooting TVs and Video Sources

    Philips 42PFL3704D LCD no power

    I bought this Philips tv about 1 1/2 years ago, from that time on two occasions the tv turned off and would not turn on until I unplugged and plugged the power cord back in.

    The third and final time it did the same thing however after turning off the tv it would not turn back on and there is no power led or standby led either.

    The remote or the power button on the tv does nothing when pressed. When I unplug and plug the power cord there is a clicking sound and nothing else.

    I have read some threads here and my problem sounds similar to some threads...
    See more | Go to post
No activity results to display
Show More
Working...
X