Timer is use in only Defrosting Refrigerators. Defrosting is controlled by an electric or electronic timer: For every 6, 8, 10, 12 or 24 hours of compressor operation it turns on a defrost heater for 15 minutes to half an hour.
the point of timer is 4. 1 and 3 Neutral and Phase and 2 and 4 is for compressor and heater . Now how we Know that which is for compressor and heater. But 1 and 3 is always for Neutral and Phase.
Multimeter Set on Continuity Point and rotate the timer Switch. one wire of multimeter attach with timer no 3 point and second wire of multimeter before attach with no 2 point and after attach with no 4 point which point is show Continuity on meter this point is for Compressor and The second point is for heater Which will not be show Continuity on multimeter.