1993 Volvo 960 a/c condition

i have a 960 1993 volvo. the a/c compressor comes on for about 2 seconds and then shuts off for about 10 ssec. and cycles back and forth in that manner, It doesn/t matter where the temp control is set. the output of the compressor seems to work as the temp of the small tube coming out of the compressor is very cold.