What am I missing, Electrical drain.
#1
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Thread Starter
What am I missing, Electrical drain.
So I have a drain on the battery that I thought I had figured out with the rear hatch. I finally bought a new battery while reskinning my headliner. The battery drained quickly while I was working on the headliner. I finally buttoned almost everything back up, charged the battery, enjoyed a nice drive on sunday, went out last night and the car was totally dead.
The only thing not hooked back up was the dome light. Could that cause such a drain? Am I missing something else up there? I wont get to do an amp draw on the battery till this weekend.
Thanks for any advice/ suggestions
Sean
The only thing not hooked back up was the dome light. Could that cause such a drain? Am I missing something else up there? I wont get to do an amp draw on the battery till this weekend.
Thanks for any advice/ suggestions
Sean
#2
Rennlist Member
Lots of potential sources. Door edge lights, glove box light, etc. I had an internal drain in my alternator.
I use voltage drop across fuses to check fused circuits. Ultimately you may need to get an ammeter between battery and car to narrow down completely.
Good luck,
Dave
I use voltage drop across fuses to check fused circuits. Ultimately you may need to get an ammeter between battery and car to narrow down completely.
Good luck,
Dave
#3
Drifting
The only thing not hooked back up was the dome light. Could that cause such a drain? Am I missing something else up there? I wont get to do an amp draw on the battery till this weekend.
#4
Nordschleife Master
I always suspect the door pin switches, but mine has been fixed a couple times to no avail, so I put in a battery disconnect switch and use it every time the car is parked more than a few hours.
Also the pin switch under the hood, idea being a flaky pin switch wakes up the alarm system, which either goes off or drains the battery some.
Also the pin switch under the hood, idea being a flaky pin switch wakes up the alarm system, which either goes off or drains the battery some.
#5
Rennlist Member
Sean,
Have you tried disconnecting the brown/white wire connector for your rear hatch? If your rear hatch doesn't seat well, it will turn the interior door lights on (which can be seen and manually turned off) and also the door safety lights will be on (the red ones in the door end) which can't be seen unless the door is open. Those will kill your battery.
Obviously, the correct fix is to get the rear hatch switch fixed, but in the interim......
Have you tried disconnecting the brown/white wire connector for your rear hatch? If your rear hatch doesn't seat well, it will turn the interior door lights on (which can be seen and manually turned off) and also the door safety lights will be on (the red ones in the door end) which can't be seen unless the door is open. Those will kill your battery.
Obviously, the correct fix is to get the rear hatch switch fixed, but in the interim......
#6
Electron Wrangler
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Which car?
if you left the hatch open - you are almost certainly illuminating the door end lights (about 4W) and on late model car you may have the power window controller active.
Disconnect the battery while working on the car - simple.
Fully discharging a battery kills it fast - you have likely damaged the new one - charge it up fully ASAP.
Alan
if you left the hatch open - you are almost certainly illuminating the door end lights (about 4W) and on late model car you may have the power window controller active.
Disconnect the battery while working on the car - simple.
Fully discharging a battery kills it fast - you have likely damaged the new one - charge it up fully ASAP.
Alan
#7
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There are a multitude of things that can cause a battery to drain overnight. As Dave, Bilal and Danglerb all suggest the interior lights and door edge lights are the most likely suspects. Removing all the fuses, connecting an ammeter in series with the battery and then putting the fuses back in one at a time and checking the meter will quickly tell you which circuit is the problem. It can be a bad diode in alternator, as well as something in the car not shutting down, such as a fan motor, the electric hatch release motor, electric window defroster, etc.. The "remove all the fuses" test will find any of these other than the alternator problem.
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#8
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Thread Starter
Thanks Guys for the input. I did disconnect the rear hatch, and that had cured my battery drain until I did the headliner. This weekend I am going to stick an ammeter on it and see what its pulling. I suspect that the dome light between the visors is the culprit. The wires are taped off a bit, and just sitting up there. It is very possible that it is either making contact with the other wire or the roof.
Ill be charging the battery tonight and fixing the dome light and will see what happens.
Ill be charging the battery tonight and fixing the dome light and will see what happens.
#9
Electron Wrangler
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You should really have charged the battery immediately - leaving it discharged for any length of time is very bad news for its long term health - of course at this point this is more for others' future benefit.
There are actually still quite a few circuits that are not protected by a fuse - hopefully you will find the culprit is controlled by a fuse. You can eliminate all the fuses that are controlled by the ignition switch (15) or Accessory (X) these will not be active with the ignition off.
Alan
There are actually still quite a few circuits that are not protected by a fuse - hopefully you will find the culprit is controlled by a fuse. You can eliminate all the fuses that are controlled by the ignition switch (15) or Accessory (X) these will not be active with the ignition off.
Alan
#10
Rennlist Member
Thread Starter
Well I finally got time this weekend to put an ammeter on the car. When I first put it on its pulling .34 amps, then drops to .15 and stays there. It is pulling from fuse 24, the interior lights. As soon as I pull that fuse it drops to 0.00.
I have disconnected pulled the rear hatch, hood light, and pulled every bulb and its still pulling a load. I did the test with the radio disconnected also with no changes.
What am I missing?
I have disconnected pulled the rear hatch, hood light, and pulled every bulb and its still pulling a load. I did the test with the radio disconnected also with no changes.
What am I missing?
#13
Rennlist Member
Pulling a bulb may not remedy a drain. The wire can rub/short to frame/enclosure of the dome light to chassis can be the cause. I would suppose that applies to any of the other courtesy lights in doors and hatch.
#14
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Also the delay relay for the interior lights is triggered by the door/hatch open and consumes approx 100-150mA even with no bulbs attached - pull the delay relay itself
Alan
#15
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