Problème alimentation

Just to confirm, a dead SMPS can be several things, if you are not an experienced technician then think about asking one to look at it for you as these things can give you a shock and, in some circumstances, can hold a charge after removing the power. Repair at your own risk!!

First, check the fuse, if it looks vaporized then you have a serious short, do not replace it without investigating further as it could make matters worse.

R102 often looks discolored due to heat, the part is a 75K 2W resistor but I would recommend changing this to a 82K 3W part, make sure you mount it slightly off the board to help dissipate heat better. This is known as the start-up resistor and is critical to getting the SMPS running.

The other common problem is C103 failing, the part is a 100uF 25v electrolytic capacitor, I replace this with a 35V device but make sure your replacement is marked 105 degrees.

I've had the odd FET fail but this is quite rare, the fixes above will solve more than 90% of the problems.