92 deville no lights where is the relay????????

i recently purchased a 92 deville 4.9 with the auto day light sentinel system, i was told to change the relay under the hood near the maxi fuse panel i didnt know which was which because they werenot labeled so i swapped each one with no success, im thinking this thing is somewhere else my chilton doesnt show a headlight relay in its wiring diiagram as well as all the parts stores i call or go to say the same thing. i replaced the switch , no fuse problems HELPPPPPPPP:rant2: