disnt know which place to post this so I though it would be good to go in here, but my car has a draw right now to the battery and it keep draining it every 3-4 days. It’s kinda weird but I was wondering if it’ll be okay to keep a battery charger/maintainer on the battery when I’m not using the car till I found out what’s draining it. Don’t like keeping the battery unplugged from the car because then it idles really weird when I first start it up again.
I'm not an expert but if you keep the tender on with a draw it will not go into maintenance mode and the tender may overheat.
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and that’s what I was afraid off. Can anyone else put any input on this if it’s true or not?Originally Posted by Carguy8888
I'm not an expert but if you keep the tender on with a draw it will not go into maintenance mode and the tender may overheat. I would go to a retail chain store and have them do a load test. If you don't want it to go dead keep it unplugged.
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I’ve had the battery tested, alternator tested, and even the starter and I was all good. I unplugged the negative battery terminal and put a test light to the negative battery and to the unplugged terminal and it lite up showing there’s a draw somewhere and have no idea where and it’s somethint small it takes like 4 days for the battery to go completely deadOriginally Posted by Carguy8888
I would go to a retail chain store and have them do a load test. If you don't want it to go dead keep it unplugged. Do you have an aftermarket stereo, aftermarket alarm or could be the amp on the monsoon radio which happened to me.
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no aftermarket anything. This all started happening after I took my car to a shop and got heads, cam, intake, and injectors installed. After I got it back it had weird starting issues when the car was already warm so I thought it was hot start issue with the tune so I took it to a local tuner and get it all retuned and everything and it’s to this day still doing it. Originally Posted by Carguy8888
Do you have an aftermarket stereo, aftermarket alarm or could be the amp on the monsoon radio which happened to me. 
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Easy test would be start yanking fuses individually till your draw goes away. It can help isolate where your problem lies.
Sometimes when this happens it is due to someone hooking up an orange or red wire (always hot) to a pink circuit (keyed hot) which will allow things to draw the battery. It is most likely an easy fix but might take a while to find. Assuming the shop did not take the interior out the wiring issue is probably under the hood and possibly from the purple wire to the starter (keyed hot) touching the main red battery always hot wire. Get under the car and check the starter wiring and make sure it is on the correct connectors.
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thank you for this info I’ll be doing that today!Originally Posted by Nostang
Sometimes when this happens it is due to someone hooking up an orange or red wire (always hot) to a pink circuit (keyed hot) which will allow things to draw the battery. It is most likely an easy fix but might take a while to find. Assuming the shop did not take the interior out the wiring issue is probably under the hood and possibly from the purple wire to the starter (keyed hot) touching the main red battery always hot wire. Get under the car and check the starter wiring and make sure it is on the correct connectors. 
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Good info right there, I know you said you had the alternator tested but it could be a bad diode, it's a one way check valve inside the alternator to keep the battery from being drained.Originally Posted by 99Silver6.0
Easy test would be start yanking fuses individually till your draw goes away. It can help isolate where your problem lies. Quote:
yeah probably gonna replace the alternator for the heck of it honestly. Pretty sure that’s not the reason as I said above this all started happening after I got my heads and cam installed but might be worth a shot Originally Posted by qweedqwag
Good info right there, I know you said you had the alternator tested but it could be a bad diode, it's a one way check valve inside the alternator to keep the battery from being drained. 
Although a bad alternator diode can lead to battery drain, their purpose is to convert (rectify) the alternating current output of the alternator to direct current for the car's electrical system - not to keep the battery from being drained. I would not replace the alternator simply because it is remotely possible that it is causing a battery drain... do some diagnostics and then fix the actual problem rather than just randomly throwing parts at it.
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Just hook up a kill switch that cuts all power. You'll still need to charge the battery though if the car sits without use for long periods of time.