I've got a 97 ES300 and for awhile it would blow cold air for a short time and then stop. Eventually it has stop blowing cold air all together. I ran the HVAC test and here are the codes I got
13
21(it was kinda dark)
42

any thoughts on what might be wrong

 

The mid-90's ES models are notorious for having expansion valve problems. I am not sure whether this problem was still present on the 97 models.

This has been addressed numerous times on this forum.

The problem usually occurs when the weather is very hot. The AC will put out cold air when first started, but after a time the air coming out is no longer cold. The fix is to replace the valve, and it's not an especially easy job because of its location.

 

I read that on this site as well and I've already replaced the expansion valve. It wasn't that bad of a job only took maybe 3 hours or so but it didn't fix my problem

 

after I changed the expansion valve what procedure should I follow to fill with refrigerant