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Hey guys, hoping for a little insight. I have a 2006 Jetta I-5 with only 50k miles. I receltly had the CAT replaced, as well as both cooling fans and battery. I now notice that everytime I use the AC, the CEL comes on. I disconnected the battery to reset the codes and no problems after driving about a week with no AC, however as soon as I engaged the AC, 5 minutes later the CEL comes on AGAIN! Any ideas what this might be? Hoping this is not another several hundred dollar fix like the CAT, and cooling fans. Thoughts?