Trying to repair a DSL that doesn't power on at all. I checked the fuses (f1 and 2) with a meter and they tested good. I know the battery is good. AC power socket is broken, so I can't test with AC. I took motherboard from a known working DSL, put it in the non-working. On power up, Green light came on, both screens briefly flashed and then turned off. I put a bottom screen from a known working unit it it and it did the same thing. Haven't tried replacing the top screen. I also took the motherboard from the broken unit, put it in a known working unit and it still did nothing. Again, the fuses tested good on it. The flashing screens and powerdown with the good board baffles me. I am hoping to not have to replace the motherboard. I would appreciate any guidance or advice on possible fixes.
if it does nothing the only other easy fix (other than a fuse) is a large component just below the power switch, this sometimes drops off if the unit is knocked. Otherwise it is a new motherboard
Are you talking about the L2 component next to the power switch? It's there and I tested it with a meter. Checked out. I had a suggestion to test f2 by putting a meter probe in the hole just behind the fuse in the circuit and the other probe on the farthest battery connection. When I do this on a good board, I get get good continuity. On the one I'm trying to fix I get nothing. Do you think replacing F2 would solve my problem? I also determined that the top screen is bad by putting it in a working DSL and it flashes. The bottom screen worked fine when I did this check.
To test the fuse put the meter either side of the component, in the charging circuit there are other components. If the fuse is good then as you have a good board it is a matter of checking each component in the circuit to see if it has the same readings
