O2 sensor wires

I'm trying to install an Air/Fuel ration gauge on a 2003 V-6 Tiburon. Problem is, I can't find any diagrams stating which wire is the signal wire. It's a 4 wire, heated sensor. I can't just put a voltage sensor or ohm meter on it due to the fact that I don't want to burn up the sensor. "huge warning in the gauge instructions" Hopefully, someone on here has installed the gauge and knows which wire I need.....please help me...thanks for any info you could give.

HOLY SHIT!!!!

check out the awesome interactive schematics webtech has with the new hyundai's...you lucky bitches.

anyway dood, go here and click on MFI control system(2.7L). page 4 is what you want. looks like it should be a red wire that you want. make sure you hit the o2 sensor before the cat too.

http://hmaservice.com/xml/Svg/2003/6/Default.asp

if you ever need anything else, be sure to check out www.hmaservice.com/webtech for help.....its great!!!!

Thank you for the info....installation went smooth from that point on. Thanks again so much.