What is the normal battery draw? - LS1TECH



Cadillac CTS-V 2004-2007 (Gen I)
The Caddy with an Attitude...

What is the normal battery draw?

Reply
 
Thread Tools Search this Thread
Old 03-30-2017, 07:48 PM   #1
Staging Lane
Thread Starter
 
Join Date: Jun 2016
Location: Dayton, OH
Posts: 69
Default What is the normal battery draw?

I did a parasitic draw test and I am getting 0.72. What should be the normal draw on the battery? I didn't drive my car for two days and the battery was completely dead. My multi-meter said the battery was at 4.8v. I took the battery to Auto Zone they charged and tested it and said it was ok. Brought the battery back home a left it on my bench for a day and it is still holding the charge. Would a 0.72 draw on the battery be enough to drain it that much over two days?
CTSvOH is offline   Reply With Quote
Old 03-30-2017, 08:41 PM   #2
TECH Addict
iTrader: (4)
 
FuzzyLog1c's Avatar
 
Join Date: Mar 2011
Location: Connecticut
Posts: 2,934
Default

Definitely. You should be under 0.1 amps. I can test my car this weekend if you want an apples-to-apples comparison.
FuzzyLog1c is online now   Reply With Quote
Old 03-30-2017, 08:44 PM   #3
Staging Lane
Thread Starter
 
Join Date: Jun 2016
Location: Dayton, OH
Posts: 69
Default

Quote:
Originally Posted by FuzzyLog1c View Post
Definitely. You should be under 0.1 amps. I can test my car this weekend if you want an apples-to-apples comparison.
That would be great if you could. I didn't want to start pulling fuses until I knew if that was normal or not.
CTSvOH is offline   Reply With Quote
Old 03-30-2017, 09:47 PM   #4
TECH Fanatic
iTrader: (1)
 
isis's Avatar
 
Join Date: Jul 2012
Location: Pittsburgh
Posts: 1,155
Default

Check your interior light dimmer. If it's on full bright that can do it. Pull it back just a tad and remeasure. Fixed my problem for 4+ yrs now.
isis is offline   Reply With Quote
Old 03-30-2017, 10:53 PM   #5
Staging Lane
Thread Starter
 
Join Date: Jun 2016
Location: Dayton, OH
Posts: 69
Default

Quote:
Originally Posted by isis View Post
Check your interior light dimmer. If it's on full bright that can do it. Pull it back just a tad and remeasure. Fixed my problem for 4+ yrs now.
I was reading about that earlier. I'll try it tomorrow and see what happens. Thanks.
CTSvOH is offline   Reply With Quote
Old 03-31-2017, 07:06 AM   #6
Launching!
 
Join Date: Jun 2016
Location: Texas
Posts: 299
Default

nominal would be zero amps, isis is right about the dimmer switch, aftermarket radios can do it as well, along with poor wiring jobs that see a constant hot wire
Anthony Toal is offline   Reply With Quote
Old 03-31-2017, 07:22 AM   #7
Teching In
 
Join Date: Dec 2010
Posts: 9
Default

That's about the current draw of a glove compartment or trunk light. Hook up your battery and meter and start pulling fuses until the draw drops to about zero. Then you'll have a better idea what is drawing down your battery.
Austin Phil is offline   Reply With Quote
Old 03-31-2017, 07:37 AM   #8
On The Tree
iTrader: (1)
 
Join Date: Oct 2004
Location: Chapin, SC
Posts: 113
Default

Maximum recommend draw for a car with today electronics is 0.030 amps a draw of 0.1 amps will kill a battery with in a few days.

Now when you test for an electrical draw you need to let the vehicle sit for 30-45 mins before you get a true reading. It takes about 30-45 mins for all of the electrical modules to time out a shut down completely.

No car built in the last 30-40+ years will have a 0.000 amp draw.

Here is how to test.

Hook your amp meter in line with your positive battery cable.

Make sure you have access to all of the fuse boxes, if you have to have a door open be sure to latch the door latch with a screw driver so it thinks the door is closed.

Let the car sit for 30-45 mins for all of the electrical modules to time out and power down completely.

Then start pulling fuse by fuse while watching the amp meter and looking for a drop in AMPs. Start with the interior fuse box as most interior fuse boxes are powered by a larger fuse in the Battery (under hood) fuse box.

Once you have found the fuse that is the source of the draw, then you need to find all of the items powered by that fuse. Replace all of the fuses, wait 30-45 mins, then start unplugging each item powered by that fuse until you have the source of your draw.

Last edited by FD3SLS1; 03-31-2017 at 07:46 AM.
FD3SLS1 is online now   Reply With Quote
Old 03-31-2017, 09:51 AM   #9
TECH Regular
 
barrok69's Avatar
 
Join Date: Mar 2012
Location: Michigan
Posts: 419
Default

The optima in my V lasts about 4 weeks without driving it. I have to charge it up if that start interval is any longer. It's been like that since the day I got it. I should dig into whats draining it and see if I can isolate it to save some battery life.

My '88 Fiero has gone a year without starting and fired right up, no issue. lol
barrok69 is online now   Reply With Quote
Old 04-02-2017, 08:15 PM   #10
Staging Lane
Thread Starter
 
Join Date: Jun 2016
Location: Dayton, OH
Posts: 69
Default

No luck over the weekend. I pulled all the fuses and tried moving the interior lights dimmer switch. I think I am just going to take it someone that has a better idea of what they are doing. I don't want to ignore this because it will end up leaving me stranded somewhere.
CTSvOH is offline   Reply With Quote
Old 04-02-2017, 08:17 PM   #11
TECH Fanatic
iTrader: (1)
 
isis's Avatar
 
Join Date: Jul 2012
Location: Pittsburgh
Posts: 1,155
Default

Quote:
Originally Posted by CTSvOH View Post
No luck over the weekend. I pulled all the fuses and tried moving the interior lights dimmer switch. I think I am just going to take it someone that has a better idea of what they are doing. I don't want to ignore this because it will end up leaving me stranded somewhere.
Please follow up with the solution.
isis is offline   Reply With Quote
Old 04-02-2017, 09:07 PM   #12
Staging Lane
Thread Starter
 
Join Date: Jun 2016
Location: Dayton, OH
Posts: 69
Default

Quote:
Originally Posted by isis View Post
Please follow up with the solution.
I will.

I guess I could try unhooking the alternator and see if that's my problem. It's just a PIA to get to it and that's a lot of work to go through if it ends up not being the problem. Is there another way of disconnecting the alternator from the battery without removing the wire from the back of the alternator?
CTSvOH is offline   Reply With Quote
Old 04-02-2017, 09:39 PM   #13
Staging Lane
Thread Starter
 
Join Date: Jun 2016
Location: Dayton, OH
Posts: 69
Default

I think I might have found an answer to my question. Let me know if anyone else thinks this will work to isolate the alternator. i could disconnect the power wire from the battery and the power wire running to the fuse box. Then run a new wire from the battery to the fuse box. This should eliminate the alternator right? Because this will just be a wire direct from the battery to the fuse box. I think I'll try this before I drop it off at a shop. I'd rather spend $15 on a wire I can take back than drop $100+ at a shop and it end up being the alternator.
CTSvOH is offline   Reply With Quote
Old 04-03-2017, 07:06 AM   #14
Launching!
 
Join Date: Jun 2016
Location: Texas
Posts: 299
Default

Quote:
Originally Posted by CTSvOH View Post
I think I might have found an answer to my question. Let me know if anyone else thinks this will work to isolate the alternator. i could disconnect the power wire from the battery and the power wire running to the fuse box. Then run a new wire from the battery to the fuse box. This should eliminate the alternator right? Because this will just be a wire direct from the battery to the fuse box. I think I'll try this before I drop it off at a shop. I'd rather spend $15 on a wire I can take back than drop $100+ at a shop and it end up being the alternator.
Why do you think its the alternator? They dont use power unless you send electricity to its poles and turn it into an electrical motor. Even by doing it your way, unless you change the alternator, you would still have the draw from that same alternator. What fuses have you tried to remove? Do you have an aftermarket head unit? Any ricey lights under or in the car?
Anthony Toal is offline   Reply With Quote
Old 04-03-2017, 08:41 AM   #15
Staging Lane
Thread Starter
 
Join Date: Jun 2016
Location: Dayton, OH
Posts: 69
Default

Quote:
Originally Posted by Anthony Toal View Post
Why do you think its the alternator? They dont use power unless you send electricity to its poles and turn it into an electrical motor. Even by doing it your way, unless you change the alternator, you would still have the draw from that same alternator. What fuses have you tried to remove? Do you have an aftermarket head unit? Any ricey lights under or in the car?
I was reading that the alternator could have a shorted diode and this could cause a draw. I've pulled all the fuses under the hood and under the backseat. I don't have anything after market on the car. And the alternator makes sense since this happened after I was messing around with the alternator trying to fix my "battery not charging" message on the DIC.

Last edited by CTSvOH; 04-03-2017 at 08:55 AM.
CTSvOH is offline   Reply With Quote
Old 04-03-2017, 09:52 AM   #16
Launching!
 
Join Date: Jun 2016
Location: Texas
Posts: 299
Default

If that is the case, then the alternator could be the the issue, but even if you do change the wires your issue will still persist, your best bet is to remove the alternator from the system completely and then test draw. I have never seen one actually consume energy before so I am a little skeptical of it being your issue, but there is always a first. I would refrain altering any more of the electrical system because you could change the characteristics of the parasitic loss in which you think you found it, but it turns it ugly face when you hook everything back up. just remove the intake tube and power steering pump, without disconnecting it, just need a 15mm and 10mm wrench/socket, move it the the front of the car, it will give you enough room to egt to the back of the alternator to disconnect it and tape it up. Please dont forget to disconnect the battery first. This will give you a draw all the way up to the wire to the alternator, should help you determine that maybe the wire could be grounding.

here is a good way to test diodes
Anthony Toal is offline   Reply With Quote
Old 04-03-2017, 10:19 AM   #17
On The Tree
iTrader: (1)
 
Join Date: Oct 2004
Location: Chapin, SC
Posts: 113
Default

There is a easier way to check the diodes. Just crank the car up and put your multi meter to AC volts, then put the leads on the battery. Anything over 0.100 AC is a sign of a bad diode. Alternators make AC voltage and the Diodes in the alternator convert the AC voltage into DC voltage by allowing voltage to only flow in one direction.

Also an alternator can have a internal short causing it to draw power, which is more likely than a bad diode.
FD3SLS1 is online now   Reply With Quote
Old 04-03-2017, 10:39 AM   #18
Launching!
 
Join Date: Jun 2016
Location: Texas
Posts: 299
Default

Quote:
Originally Posted by FD3SLS1 View Post
Also an alternator can have a internal short causing it to draw power, which is more likely than a bad diode.
I would think that as well, but from his other thread he says he is getting good output voltage on the alternator. he would know if he had bad windings and depending on the ACDC circuit with the regulator, the only other thing that would prevent it are the stator/exciter diodes, which i dont know if our cars use them or not.
Anthony Toal is offline   Reply With Quote
Old 04-03-2017, 09:57 PM   #19
Staging Lane
Thread Starter
 
Join Date: Jun 2016
Location: Dayton, OH
Posts: 69
Default

Here we go.. I unhooked the alternator, the draw went away. Did the diode test from the video Anthony Toal posted. The alternator pasted. Connected the power wire back to the alternator and there is no draw. I disconnected my multimeter, plugged the pig tail back into the alternator, run the test again, there's a draw. I disconnect the pig tail, draw is still there. I unhook the multimeter. Wait a few minutes for the system to shut off. Run the test again, this time only the power wire is connect in the back, I am still getting a draw. I disconnect the multimeter, disconnect the power wire in the back, run the test, no draw. Ok connect the power wire back, run the test, no draw, so I connect the pig tail back while the test is running, no draw. I also ran the test with power disconnect from the alt. but the pig tail still plugged in and there was no draw. WTF is going on? Every time I do something different I get a different result. One thing is for sure though, If the alternator is disconnected from the battery, there is no draw.
CTSvOH is offline   Reply With Quote
Old 04-04-2017, 08:05 AM   #20
TECH Fanatic
iTrader: (17)
 
AAIIIC's Avatar
 
Join Date: Aug 2007
Location: Where the Navy tells me to go
Posts: 1,510
Default

I need to go through this troubleshooting, too - it's on the list of too many things I need to get done on my 4 cars.
AAIIIC is offline   Reply With Quote
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
QTP wireless cutout power draw? wayland1985 Stereo & Electronics 0 04-09-2017 05:45 PM
Parasitic draw from hell, pulled all fuses, still have draw eb2phkingood Stereo & Electronics 4 04-23-2015 09:34 PM
Battery keeps going dead after sitting a few days chevrev Conversions & Hybrids 12 11-30-2012 09:13 AM
Help - 2006 chev equinox goes dead Cheryll User Support & Resources 1 09-14-2012 04:39 PM
amp drawn lsx swap kevmac Conversions & Hybrids 1 09-08-2012 09:16 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 05:41 PM.


 
  • Ask a Question
    Get answers from community experts
What's your question?
Send