battery drainage

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86boy
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battery drainage

Post by 86boy »

So my has a bone stock GTS and the battery slowly drains. Thought it was the battery...replaces it same crap. Also checked the charging system, and its still charging at 14.1v. It is fine if you drive it everyday but if you let it sit for 2-3 days back to a dead battery. Mind you these click with the key off and out of the ignition completely.

Then noticed the VSV bolted to the MAF, and the TVIS solenoid "click". Is the VSV supposed to click? I don't remember those doing that on mine when it was bone stock. If the battery is charged and you touch the negative to the negative *click* release it *click*. So checked the ground to the VSV and its all fine and dandy.it has continuity back to the negative post on the battery. Disconnected the MAF then core no change with the solenoids clicking. Finally disconnected the 10 pin connector and neither TVIS or the VSV clicks. Had a spare ECU still the same crap. Checked all the grounds on that connector and everything seems good. I'm just out of ideas on what could cause that.
      "Praise the Lowered"
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bt20v
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Re: battery drainage

Post by bt20v »

check the dome light in the trunk...bet it could be staying on when the trunk is closed draining the battery....took me 4-5 days to find that one when it got me.
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86boy
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Re: battery drainage

Post by 86boy »

bt20v wrote:check the dome light in the trunk...bet it could be staying on when the trunk is closed draining the battery....took me 4-5 days to find that one when it got me.

yep he did check that already haha!

My friend has been disconnecting his batter at night so it stays charged up. When he disconnects the battery he said he can hear vacuum being released. Which could very well be from that TVIS vacuum solenoid under the intake manifold and/or the one next to the air box. I'm not 100% sure what would cause those 2 to stay energized with the key OFF and out of the ignition. I'm pretty sure that's where the drainage is at, but we tried a different ECU and checked the grounds.
      "Praise the Lowered"
          _____________
       // ---------------- \\
   _// ______________ \\_
 /__________|__________\
|OOO _____________ OOO|
 \________|1964|_______/
    ¯¯                          ¯¯

ga_goosh
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Re: battery drainage

Post by ga_goosh »

tell your friend to try to unplug the vsv on the afm if it is suspected. the car will run just fine with out it. the idle may dip slightly but it is a good way to eliminate that problem. you can aslo do the same with the tvis too. it will just be a bit slugish below 4000 rpms or so. you can get the ecu pin out and see if the ecu is getting power when the car is off. if it is then you know where the problem would be or at least a good starting point.

is there any components that are hooked up that are not functioning correctly? there could be a short in one of those if any. has any electrical mods been done maybe a stereo or something simmilar?
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dr.occa
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Re: battery drainage

Post by dr.occa »

Check that no door open lights are on at all when the car is shutdown and closed up for the day. Does the door open light even come on when the doors or hatch open?

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86boy
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Re: battery drainage

Post by 86boy »

I'm 99% sure the drainage has to do with that VSV and the TVIS. No mods all stock. No door lights or trunk lights either. The grounds to those two appear to be good. Good continuity and resistance. Is there another ground for the ecu besides the intake manifold?

When he disconnects the battery you can hear the vacuum bleeding off from the TVIS... So its never releasing. As soon as you hook the battery up you can hear it *click*
      "Praise the Lowered"
          _____________
       // ---------------- \\
   _// ______________ \\_
 /__________|__________\
|OOO _____________ OOO|
 \________|1964|_______/
    ¯¯                          ¯¯

humble1
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Re: battery drainage

Post by humble1 »

Try this if you havn't yet. Help detect Battery drain.


http://www.youtube.com/watch?v=KF1gijj03_0" onclick="window.open(this.href);return false;

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86boy
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Re: battery drainage

Post by 86boy »

humble1 wrote:Try this if you havn't yet. Help detect Battery drain.


http://www.youtube.com/watch?v=KF1gijj03_0" onclick="window.open(this.href);return false;
THAT is awesome! thank you! I was trying to think of a way to test for that, but couldn't come up with anything to test for amperage. Noooooww that I know you can run a 10A multimeter... It's on.
      "Praise the Lowered"
          _____________
       // ---------------- \\
   _// ______________ \\_
 /__________|__________\
|OOO _____________ OOO|
 \________|1964|_______/
    ¯¯                          ¯¯

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