Need to confirm battery draw spec

[Ridin'GMC]

I've chased this battery drain issue for quite some time and could never find the issue. Checked for parasitic draw, comes to .78 mA every single time. Pulled literally all fuses and relays with zero change. Unplugged all accessories as well, still comes to .78 mA. I'm only running a single battery with upgraded 275 amp alternator, 1/0 battery cables all around (big 3 upgrade). Grid heater and fuel heater has been deleted. The truck doesn't get used in the winter which is why I run a single battery due to the twins. Alternator is fine since I've disconnected the alternator to verify it's not drawing power.

Every 4 days or so, the battery would drop to 11.7-11.4 volts after charging it. This is when I don't use the truck for a week. Every time I shut the truck off and check the parasitic draw, it's always .78mA, even leaving the ground cable off overnight without opening the doors to see if the modules sleep after 30 minutes or so. All grounds are good. The battery has been replaced last year, apparently I've changed the battery 3 times in the past 3 years (each time under warranty), twice due to battery ballooning in the winter. I'm starting to think the battery quality is junk even when it passes a battery test. Is the parasitic draw acceptable or should it be lower at least .6 mA or lower?

 

[2004LB7]

It's been a while since I've done my own parasitic draw test. But I thought it was around 10 to 20 mA draw when all the modules went to sleep.

How are you measuring the draw? Are you pulling fuses and putting probes in the slots? Or are you measuring the voltage drop on the fuses? The correct way is voltage drop on the fuses

A good battery will loose about 20 mV per day of sitting unused in warm weather. With your voltage it should take at least two months if the battery is good. Have you tried disconnecting the battery and seeing if the battery voltage continues to drop? Do you have any contamination on the battery that current can leak through?

 

[2004LB7]

 

[2004LB7]

- Moved to electronics -

 

[Ridin'GMC]

I disconnected the ground on the battery and used the multimeter in series from the battery ground to the ground cable and measured in mA. While doing this, I pulled each fuse to see if the amperage drops. I've done a voltage drop and gotten similar results. Now, I did disconnect the ground cable from the battery but not the positive side and checked battery voltage. Last night was around 12.7. This morning it dropped to 12.54. I'm going to check again when I get home from work to see if it continues to drop.

The battery that was left in over the winter swelled up and I removed it in the middle of the winter. I had another battery sitting on my bench that held 12.3v the entire winter. Threw that in a couple weeks ago once the snow melted. Now I'm getting the same results since last year. 3 different batteries and they all drained. If I l don't use the truck for at least a month, I've gotten down to 3v. It does have aftermarket radio and I ruled that out by pulling out the fuses. However there were times where I caught the door switch would not turn off my radio and the edge insight, sometimes I had to open the rear door to shut them off and I would unplug the insight.

 

[2004LB7]

Nothing plugged into cigarette lighter?

 

[Mikey52]

Can you put a battery tinder or trickle charger on it when in storage?

 

[Ridin'GMC]

Nothing plugged into cigarette lighter?

Nope. I never leave anything plugged in the cigarette lighter unless I'm charging my phone and it gets unplugged right after it's charged unlike my wife lol.

 

[Ridin'GMC]

Can you put a battery tinder or trickle charger on it when in storage?

I can but that's not my point. Battery dies every 4 days or so. I shouldn't have to charge my battery or leave on a trickle charger if I'm not using it for a week. It's never done this in the past where I can go for 2 weeks and jump right in and fire it up.

 

[2004LB7]

Let us know how the battery does when you leave it disconnected

 

[Ridin'GMC]

Last night I checked the battery voltage with the ground disconnected and positive still on. Checked parasitic draw, still at 78mA while not opening the doors in the truck after being stationary for a whole day. Battery voltage was at 12.56v at 8:30pm. Checked this morning at 8:30am and it dropped to 12.43v. Checked parasitic draw again while not opening the doors to wake any modules, still the same of 78 mA. Connected the ground back on and didn't open the doors still, so the truck has not been opened or started for 2 days straight. Got home and checked the battery voltage as I connected this morning, voltage continued to drop to 12.32v. Clearly this tells me the battery brand quality is junk as I've gone through 3 in 3 years now while my first set lasted a good 5 years easy. Each time I had it checked and they said it's fine....yea okay.

Guess I'll be looking into a different brand which is probably Optima. I've had good luck with those in the past and hoping they are still good enough today, knowing that they're made out of country now compared to my first Optima that was US made. Going to go for the yellow top as it is a semi deep cycle which is more suited for my truck sitting for days. I'm not sure if I should go back to dual battery setup which obviously will give a longer battery life if it's been sitting for a while. If I do, it'll obviously have to be mounted on the frame for the passenger battery. Just not a fan of having more crap underneath it when I'm planning to have onboard compressor and possibly a larger fuel tank for the long towing trips.

 

[2004LB7]

How are you checking the draw with the ground disconnected. Adding and removing the ground is going to wake up all the modules each time. Not sure I understand your process. Doesn't look correct

Also, optima is Chinese brand now and has fallen severely in quality. I just use the Duralast ones from AutoZone. Have had good luck with them. Typically get around 5 years. Other use ones from Napa, Costco, Walmart, O'Reilly's, etc and have good luck and bad luck. No such thing as a best brand. Especially considering there is only two or three manufacturers left making them

 

[Ridin'GMC]

How are you checking the draw with the ground disconnected. Adding and removing the ground is going to wake up all the modules each time. Not sure I understand your process. Doesn't look correct

Also, optima is Chinese brand now and has fallen severely in quality. I just use the Duralast ones from AutoZone. Have had good luck with them. Typically get around 5 years. Other use ones from Napa, Costco, Walmart, O'Reilly's, etc and have good luck and bad luck. No such thing as a best brand. Especially considering there is only two or three manufacturers left making them

Checking parasitic draw is to disconnect the ground cable from the battery and connect the multimeter in series from the battery ground to ground cable while leaving the positive cable on the battery. It's the correct way to check for parasitic draw by measuring in ampere. It's one of the few methods done and that's what I've done in the past to find what's draining the battery. Another way is getting a clamp on meter and leave it on the ground cable with the battery connected which is obviously easier. You may want to look into this method, pretty easy to understand.

The battery I'm using is Everstart from Walmart. I've had Napa and Duralast for my other vehicles and they didn't last long as well. Everything is gone to shit since the pandemic.

 

[Chevy1925]

Checking parasitic draw is to disconnect the ground cable from the battery and connect the multimeter in series from the battery ground to ground cable while leaving the positive cable on the battery. It's the correct way to check for parasitic draw by measuring in ampere. It's one of the few methods done and that's what I've done in the past to find what's draining the battery. Another way is getting a clamp on meter and leave it on the ground cable with the battery connected which is obviously easier. You may want to look into this method, pretty easy to understand.

The battery I'm using is Everstart from Walmart. I've had Napa and Duralast for my other vehicles and they didn't last long as well. Everything is gone to shit since the pandemic.

What Jason was getting at was that your last post was unclear in some areas as to how and when your checking voltage. You kinda bounce around between checking draw, to just checking battery voltage drop with cables off and then cables on. It took me a few reads to follow what you were doing

 

[Ridin'GMC]

What Jason was getting at was that your last post was unclear in some areas as to how and when your checking voltage. You kinda bounce around between checking draw, to just checking battery voltage drop with cables off and then cables on. It took me a few reads to follow what you were doing

Ah gotcha.

What I did was checking in various methods. First checked draw by disconnecting the battery and put the multimeter in series to check for average draw by reading in milliamps. Went through all the fuses and relays while battery ground cable is disconnected as the multimeter is in series from battery ground to ground cable. Once that was all done, I decided to check the voltage with the battery ground disconnected the entire time as it sat for 2 days, while checking amperage draw after checking the voltage reading. The amperage draw was always 78mA every time I checked it while it was sitting.

So the battery has dropped from 12.7 to 12.32 while the ground cable was disconnected from the battery but the positive cable was left on the battery. Amperage draw was a consistent 78mA the entire time, even if I opened the doors to see if the BCM would wake up or etc. Last night I reconnected the ground cable back on the battery and it dropped from 12.32 to 12.18 overnight. So... Junk battery.

Hope that clears it up. Sorry for the confusion.