PB MLT168A for an Akai LCT2701AD LCD TV

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  • orgud030364
    New Member
    • Mar 2014
    • 2
    • US
    #1

    PB MLT168A for an Akai LCT2701AD LCD TV

    I am new to troubleshooting TV's but had taken electronics courses in college 8 years ago and I am finally using my knowledge on TV's left behind in the garage by my growing children. I have a power supply board model MLT168A which was dead. Found several bad caps so I purchased the MLT168A kit and replaced the bad caps with the new. I finally got power output as following:

    5v = 4.97v (found in CON4)
    9v = 11.67v (found in CON5)
    12v = 11.67v (found in CON5)
    24v = 23.9v (found in CON7)
    24av = 20.8v (found in CON6)

    Voltage readings for 9v and 24av are incorrect.
    removed Zener diodes 4 and 5 which desoldering Zener diode 3 on one end and tested using a multimeter. Also desoldered three rectifiers without removing from board and also tested with the multimeter. All of these show they were good.

    what could be the problem?
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