I have a 98 S70 GL a/c worked great for 2-weeks , droped it off a the local shop they replaced the dryer/filter said it had a leak,now a/c works for 2-3 mins. then stops,also has codes P1308 & P0453 .i clear the codes a/c works for a few mins. then quits. the codes wont clear for some reason. changed the sensor for P1308 no difference.also changed the high & low pressure switch's. please help thanks