My fridges srs540hp keep on beeping every 2 to 3 min and the light swicth of by itself we already relplace the light swith but didnt do anything the problem still the same

SOURCE: Noise from Deodorizer

Your defrost sensor is not working and is allowing a large build up of ice in the fan compartment situated behind the interior back panel (low down) in the fridge compartment. What you hear when you open the door is the fan slowing down (the fan is switched off because you opened the door) and the blades are striking the ice build up making a scraping noise which stops when the fan stops. Removing the inner panels (two, top & bottom) will allow you to get in to the fan area & then defrost manually. ( I use a wallpaper steamer which takes about five minutes to get rid of the ice) Note the topmost inner panel has a couple of electrical connectors to the interior lights which you must disconnect before you can remove the panel. The final solution is to replace the defrost sensor then sell it quick and buy a better designed fridge freezer!! VeloFellow

SOURCE: fridge tempertature

I have the same symptom too - freezer temperature flashes at -2. "Power Freezer" or setting it to any other temperature is not working either.
As a result, no ice being made. Please help!

SOURCE: loud noise from the freezer side

The problem is a buildup of ice on the plastic housing (the curved plastic bit) in the back of the freezer under the fixed shelf where the icetub goes. The fan behind this plastic housing is hitting the ice when the defrost comes on.

Unplug the fridge, unpack the freezer, remove the four screws in the back, take off the sheetmetal backing and let the fridge thaw. You can remove the plastic piece after a while and get the ice off (be careful not to remove the styrofoam insulation by going too quickly).

Reassemble and you're back in business, for a few months. I'm never buying Samsung again myself.

SOURCE: SAMSUNG RS20CCMS AMERICAN STYLE FRIDGE FREEZER

in the freezer section there is a 6 screws. unscrew them and remove the back panel. there will be 2 wires attached to the panels, remember where they go. you will see a metal evaporator which will be filled with ice. this is the problem. use a hairdryer to melt the ice. this is essential as you mustn't puncture the wall of the fridge with any sharp item. before replacing the panel ensure that everything is dry or ice will reform, and also ensure that the fan blades are turning properly or cold air will not be blown into the fridge.

SOURCE: my fridge freezer made by samsung is on the blink

These fridges have an evaporator fan motor on both sides - the freezer and fridge side. The freezer can maintain it's temperature because that fan is working fine. I had the same problem, and replaced the evaporator fan motor on fridge side, and it solved the problem. Also, if your fan motor is not working well, or stops working, the evaporator is prone to ice build up, and will prevent proper cooling. You may want to open up panel on fridge side and see if that's the case. Taking a blow dryer to the evaporator and surrounding area (while fridge is off), or letting it sit for a few hours might solve the problem. Ultimately though, it appears as if these fan motors are prone to failure, and need to be replaced.