My 2004 Sebring v4 suddenly had its engine light on while I was driving back from work today. The diagnostic code (read through On-Off-On-Off-On) shows P 73. allpar.com does not have the code listed. The only thing I could find was for a Jeep Grand Cherokee, which says it means "Ambient temperature sensor input above the maximum acceptable voltage.". Is that correct? If so, what is an "Ambient temperature sensor"? Would it be a costly repair? Thanks.