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Test for a drain on the battery by a usingan ammeter. Disconnect the negative battery terminal and hook the ammeter withthe positive test lead on the disconnected negative battery cable and negativetest lead on negative battery post. Turn everything off, close the doors and ifyou have a hood light remove the bulb.
With the negative battery terminaldisconnected, an ammeter between the cable and post see if you have adrain showing on ammeter. A reading on the ammeter over 50 milliamps shows thatsomething is draining the battery. If so, start by unhooking the smallwires at the alternator and see if the ammeter drops to under 50milliamps. If the ammeter now reads zero or less than 50 milliamps thenyou have found the short. If the ammeter is still more than 50 milliamps, theshort is somewhere else. If the ammeterjust drops some, you still have a drain somewhere else so start pulling thefuses 1 at a time and when you do find out when you pull a fuse and the draingets lower then put the fuse back in hook up the battery and make sureeverything on that circuit works. Let me know which fuse you pulled and I'llupload the wiring diagram so you can check everything on that circuit and makesure that it works. If something doesn't work on the circuit that is causingthe drain then it may be short-circuited with another circuit of shorted toground. That may help find where the short is if something don't work. Sowith your 12-volt test light or voltmeter test the wiring to whatever doesn'twork to find out where it has voltage and all of a sudden looses voltage andthen repair that spot. If any drop some or allot write it down which fuse itwas and write down how much milliamps it dropped. Remember if you have to keepthe door open to pull the fuses just push in on the door switch after everytime you pull a fuse and go to look at the meter. When all fuses are pulled andthe alternator wires are off you should have no drain and written downeverything that was causing a drain. If you still have a drain with every fusepulled and the alternator wires off, then it must be something that is unfusedsuch as anything that may be fed from the light switch or fed from a fusiblelink. Last if you have all the fuses outand still have a drain disconnect the big wire at the alternator. If the drainnow goes away you have a bad diode in alternator.