As of early 2008, there was a recall on a defective wiring harness that turns the Suzuki Forenza headlights on, the wiring literally frys, but this is covered under the recall, so go to your nearest Suzuki dealership and have the repair done, free of charge.
Bulbs blew
there are two diff types of bulbs. High beam and low beam bulbs. If your low beam doesn't work then you need to replace those lights because they are probably blown.
replace high/low beam switch
The daytime running lights work of the high beam, check those first.
Have you checked to make sure both bulbs are not burnt out on low beam? Even if it is a single bulb for both high and low beam the low beam filaments could be burnt out.
Try the light switch
You have different bulbs for low and high beam. Go to an auto parts store and tell them you need two bulbs for you car, low beam. Look in your owners manual on how to change your bulb. You shouldn't need any tools to do this.
if you've tried hitting the high/low beam switch & headlights are out on both, then a bad headlight switch or headlight switch plug or high/low beam switch plug not fully engaged.
if your low beam lights run off a relay, then that might have expired. will need replacing if it has.
The problem may be the electronic module that controls your daytime running lights. If there is a plug to the module, unplug it and the hi beam lights will work. The Hi Beam light indicator may not work now though until you replace the module.
your bulbs are burnt out. when you switch on the high beams its only the high beams. but when you flash your brights it lights up both high and low beams.
Check fuses and high/low beam switch.