looks like the same problem as lewismug posted on aug.7th except that mine mostly works at low speeds. the compressor kicks on and off. when it is on it cools good, doesn't that mean the system isn't low on freon or gas? i will buy a pressure switch and change it out if others here have had the same experience and that worked. seems like a high/low pressure thing. i can have the codes checked, (i didn't know that the odbc supplied codes for A/C). i brought it to a local guy and he said that he didn't want to try to throw money and parts at it because he would only be guessing without proper volvo system analysis equipment. i can go to autozone and check for any codes. any help is appreciated.

thanks,
wayne