Can anyone help me to fix this board?

[d1ng0]

Hi guys, im a newbie but i love eletronics its my first post so if is bad sorry XD. I've been trying to fix the 18v battery charger for a few days but so far I haven't managed to fix it. So what happens is the following: I measured the voltage on the diodes and they are all above 0.5V so they are good; The capacitors are not swollen and I measured it with an ESR meter and it didn't give any high esr value, so they should be good too. I powered the board and on the left side of the metal part all the components have voltage, all the resistances and so on but none of the right part have it and I don't know what else to do. Can someone help me? ps. This is a toptul battery charger 18V.

 

[barry]

Without a schematic its impossible to even guess what’s wrong. But high ESR does not mean a capacitor is good; I would think just the opposite.

 

[d1ng0]

Yes but i can´t find any schematic online, if someone can find pls tell me. Its a Toptul battery charger 18V. Yes, i measure with the ESR meter and all capacitors gave me low ESR value.

 

[barry]

Ah, sorry, I misread your low esr comment. What about shorted caps? I think a low ESR doesn’t tell the whole story about the health of a cap. But unless you can maybe find a broken trace, there’s no way to tell anything. It’s like me asking you to tell me why the car on the side of the road doesn't run; maybe it’s out of gas, maybe it’s got a broken crankshaft.

 

[FvM]

Did you check input fuse F1? Common fault of SMPS is shorted primary transistor blowing the fuse.

 

[pjmelect]

As you don't have a circuit diagram look for the data sheet on U1, they normally have a sugested circuit which will be close to the circuit on the board.