IBM L170 power supply failure

IBM L170 power supply

IBM L170, manufactured in May 2004, model no. 6734-AB1

The screen would turn on fine, but when a signal was applied, the backlight would turn off.

Capacitors C201, C223, C922, C924, C925, C926 had failed. Capacitors C924, C925 and C926 are situated on the 5V rail and were successfully replaced by used 6,3V Chemi-Con KZG and Nichicon HM parts of equivalent capacitance. C201, C223 and C922 are situated on a well-regulated 12V rail. C201 and C223 were collectively replaced by one used 1500µF/16V Chemi-Con KZG (they’re directly in parallel with about 1cm of trace in between). C922 was replaced by another such.

IBM L170 power supply after repairs.

I should end with noting that these are some of my favourite consumer LCD screens ever made. Aside from the the power supply, the build quality is staggering. They weigh six kilograms and ship with a proper, extremely high-quality 100×100 VESA stand that you can bolt onto any monitor you wish, for an instant improvement in stability. They’re screwed together rather than snap-locked, and the serviceability is just staggeringly good all-around.


One thought on “IBM L170 power supply failure

  1. Salaam to all,
    I have same board 715L1013-1A-1…..
    I chang capacitors but supply still not working.also i chang FET and IC but supply not working.
    Anybody can help me for this problem???also value of resisters ( R906 & R907 )
    ( i put 1M ohm)

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