Trouble w/ my 90 Accord, help?

I have a 1990 Honda Accord, after I park the car within 10-15 minutes the cooling fan goes on while the car is off... Its on for about an hour to two hours and makes a clicking sound near the relay... its stops momentarily..makes clicking sounds...then starts up again... & it doesnt stop until it drains my battery.. I changed the relay twice and realized that this isnt the problem...
Anyone know what may be the problem?

Any help would great!