Headlights Do not work- Low beams only

[samsony]

I have been running without Low beams for weeks now. I am not sure if its a simple issue or something complicated.
I am a noob when it comes to cars. i had a friend who installed fog lights on my car, he moved to another state now. He connected 2 wires from the fog light relay to the low beams(I didn't have to change the turn signal/headlight switch), so when I turn the low beams ON, fog lights used to come ON as well. Everything was perfect until one night when I parked my car, my lights stayed ON for more than usual time. I tried to manually switch it off but it stayed ON. I went under the hood(went to IPDM- passenger side) and removed the relay for the low beam, and the lights went OFF. I connected it back but the lights never came ON after that.
Things I have already tried.:
1) tried a new turn signal switch - NO GO
2) Replaced both head light bulbs - NO GO
3) Checked low beam fuses on IPDM - Everything looks OK
4) Swapped the relays - NO GO

I dont know whats up with it?
Did i burn the wires or socket or something?
The thing is both the low beams do not work. so somewhere the circuit is broken i believe.
Please HELP! been driving at night with the high beams lol
Thanks
Sam

[sx moneypit]

Nissan has had some problems with the IPDM units but you might also have a problem with the BCM. You need to get the car scanned for trouble codes and to do some functional tests.

-Ben