Drain on the ol' battery

Discuss the RB20, RB25 and RB26 series engines.
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govtworkhorse
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I don't know too much about electronics first off. Anyways, it seems as though I have a pretty heavy draw on my battery at all times and everytime I want to start my car I have to jump it. The battery has been tested and is good as has the alternator. But when I shut the car off, it needs jumped again (sometimes it will start within an hour or so). Like whatever is shorted out/draining my battery is doing it at the same rate ad the alternator is charging. Oh and the reason I figure something is shorted is because the positive battery cable has a plastic connector attached to it that has melted. If you have any idea what I'm talking about, could you give me some advice on how to track down the problem?

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Cpt_Impossible
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You first need to find out how much power is being drawn. Put a multimeter on amps and touch the +battery terminal and the +cable and hold one on each as you slowly pull the cable off of the terminal. I think reasonable is .04amps or less. Then start testing things that should be off to see what still has voltage. It is usually something like the trunk light switch being jammed and staying on. In my case it was the green relays by the ecu being wired incorrectly.

Did this problem start with the swap or just recently? What have you changed lately?

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govtworkhorse
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Well I made a mistake and bought a car with a swap already done because at the time I had no place to build one. Could be anything. I bought the car a year ago tomorrow and have yet to drive it (maybe 150 miles) due to body work needed to be done and my work schedule. But the guy said it had just started doing it right before he wrecked it so I don't think (hope it's not) something mis-wired in the harness. I haven't changed anything at all. It just sits in the garage. Sorry for the lengthy reply but I needed to make sure you understood where I was coming from.

SR2OM0NSTER
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where's your battery located? if it's where the damage was done, maybe there is a ground issue there or the battery might have been hurt..

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Kansei240sx
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Yeah, just like Cpt impossible said. Take a Dmm and measure amperage between the positive terminal and the positive post, basically put the Dmm in series of the Battery. If you have a considerable amount of drain, even 3 amps will do it. Trace the draw of amperage. Find out where it stops drawing and you might have found your culprit.

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govtworkhorse
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SR2OM0NSTER wrote:where's your battery located? if it's where the damage was done, maybe there is a ground issue there or the battery might have been hurt..
Battery is still in stock tray so it wasn't near the damage. Good thinking though. I just bought an S14 with blown motor so I'm going to swap over the RB and hopefully I'll catch a glimpse of what it may be. Or I might just F it up more...


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