Wind chill does not lower the actual temperature. To simplify what wind chill is - It is a measure ment of how fast something would lose heat if there was no wind. If it lowered the actual temperatures our radiators would surely freeze a 80 miles/hour.
You said you switched and grounded your yellow wire, all that I have read indicates you should have done this to a yellow / black wire. Was this a typo or did you do the wrong wire?