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My name is Dale.
You need to check for codes with a scanner through the ALDL Port. If there are not codes then you will need to hook a (In Series Tester) in the main feed from the battery. It usually goes straight to the Alternator and is a fairly large wire. You will need a tester like this: Which you can pick up at any auto parts supply or Harbor Freight.
You will be able to trace the electrical draw or drain on the system via the magnetic meter that comes with the tester. The tester sends a impulse through the electrical circuits so you can isolate where and which components is coming on.
I suspect that the coolant sensor, relay or switch that cycles your cooling fans may be the problem. But in any case, you will have to isolate the circuit, either by pulling 1 fuse at a time and testing to see if the problem duplicates itself or use the tester if there are no codes in the computer system.
Have a Blessed & Prosperous Day,