there is an easy way to find out which power circuit is draining power from your battery, a parasitic load...

On each fuse of a 1987 or later model you see two bits of the actual metal contact strip protruding the plastic material. Two dots on top. Now, taking that a fuse is a small wire that burns when it is heated by a current higher than its rating, it is like a resistor. The resistor heats up by the current and blows.

Since it is a low rating resistor, a current will show a voltagedrop over the fuse. Use a good voltmeter in mV scale. Today most DVM will do fine for this purpose. If the current is substantial you will see a voltage of 4mv or so over the fuse. That will show you which fuse is drawing current without removing each and every one. As soon as you know which fuse is causing a drain, remove that one and use the AMPS scale on your voltmeter to measure how much. (be aware that a DVM has a limited capacity for measuring amps)

Remember that the voltage drop depends on the resistance of the fuse, and each rating will have a different resistance value so a different voltage drop at 1 amps current.

If you have a short circuit, this may also come in handy: conenct a bulb on two short wires and spade AMP connectors that fit in the slot of a fuse. Solder a 12v/25watt bulb to the leads. Remove the fuse that breaks.  When ignition is turned on the bulb will glow based on the amount of current drain. if the load is normally high it glows fairly well. If not, you may not see any light. But if there is a shortcircuit, the blub is fully on. This little device saves you from putting in more and more fuses before the short circuit problem is found.