Have you tried to repair the solder joints on the 0.75 Ω resistor?

not yet but it's weird that it worked the first day and then not any more. I going to repair it today. Can you actually damage the 0.75 Ω resistor while soldering it ? because I'm working with soldering iron and that thing is really small

 

I do not know...

It's a relatively large resistor (Imperial 1206, I think), so I think a little fresh solder can fix the problem?

If it was here at my job, it would be to solder the resistor out, remove all the old solder on both PCB and component, cleaning all the old flux residues and then solder the resistor back on the PCB again.

 

This is close to what you need: http://www.ebay.com/itm/MR16-3x1W-l...es-/192068541392?_trksid=p2141725.m3641.l6368

So is this: http://www.ebopto.lightstrade.com/view/65744/12V-LED-Driver-250mA-EB905.html

With either, you could use a resistor in series to reduce the current just a little more to get it down to your target. Something like a 10Ω, 5W resistor. (I'm just guessing at the Ω value.)

 

So I tried to repair the solder joints on the 0.75 Ω resistor but without success. I mean I I did it again but still nothing.

This is close to what you need

is this one not ok ? i see it's adjustable http://www.ebay.co.uk/itm/TOP-DC-DC...095221?hash=item43e6bf2475:g:z7MAAOSwYHxWK9uH

 

That looks good. It might be a little touchy to adjust the current at that low level since it's such a small portion of the total range, but if you can get it adjusted it should do the job.

 

I adjusted everything with a normal 12v bulb and today I installed the board.
Thank you guys for helping me with this, I really appreciate your time. Right now everything works fine, you helped me save a lot of money. Thank you once again