Not an a body but.................

I have a problem with my 09 Ram 1500 4x4 hemi....my low beam headlight on left side does not work..I replaced the bulb with a new one and still not working,(high beam does work).I checked all fuses and they are good so I replaced the bulb again with the good one from rt side.still not working........Looking on the ram forums this seems to be a common problem.they say the ecm is bad and about $800.00..I cant pay this for something when I don't know if it will fix the problem.The truck runs and drives great. .....Any suggestions ? THANKS.....................................jeff