Battery drains within 15-20 min

Riklimoguy · June 9, 2020

Hi guys!
So here’s the skinny.. I’m stumped!
2018 Yukon XL SLT. 60k mil on it! A week or 2 ago, I started having my battery drained/dying on me randomly. I would start it in the morning with no issues whatsoever. Take a drive to the grocery store turn the car off, windows open, radio on!! Radio would turn off normally after 5m or so.. (Car completely off at this point) Before heading into the store, after playing with my phone for 20-30m, one day I decided to turn the car on after it had been at the stage described above!!
immediately the battery was spent, after a few similar episodes and begging ppl for a jumper.. I decided to put a brand new Battery, did that last Saturday! 2 days later back to do groceries, following same routine, as Described above, (thinking’ brand new heavy duty 200$ battery, nothing to fear, it happened again!! )

So I bring it it to my mechanic around the corner, does a quick test, says alternator bad, battery not getting enough charge!! Sooo In goes a new alternator.. All good! Amps solid! This morning woke up, car started fine, on my way home, stoped at Walgreens played with phone for 30m or so, then got out and into the store. 15min later get into the car, battery Dead again!! .
Two things I’ve noticed so far 1: if I park the car, and immediately exit, luck it up go about my business for 30/45/1hr or whatever when I get back, car starts immediately!
2: when I get home: exit the car, luck it up, car in the driveway 10/12 hrs, Car has no issues starting up immediately either.
I mean, what the heck is this? Some sort of short Circuit while I’m in the car and the car standing by, and car obviously unlocked?
Ignition issues?
Fuse issues?
Oh, and while Battery is drained, and car won’t start, every single electronic works inside.
im completely out of clues? I’ve checked for any sort of lights hanging on, nope! All off during the period described above!!

Any help would be greatly appreciate it!
Thanks, Rick!

Edited June 9, 2020 by Riklimoguy

diyer2 · June 9, 2020

If I understand your post?

2012 Sierra

If I park, radio on, turn ignition off. Radio stays on for a while then shuts off. Normal.

It's Tim · June 9, 2020

Resistance in the negative battery cable.

Riklimoguy · June 9, 2020

1 hour ago, It's Tim said:

Resistance in the negative battery cable.

Would you be a bit more specific? How does that happen? And what’s the fix for it?

Russ Swift · June 9, 2020

Just a thought, if yours is like mine. One push on radio just mutes the radio. Radio is still on the 10-15 minutes after engine turned off. Need to press and hold to turn off radio. Not sure if will add any useful info. In my past a battery problem was found to be a bad ground someplace on the vehicle. I’ll be watching to see how you solve this. Good luck.

It's Tim · June 9, 2020

1 hour ago, Riklimoguy said:

Would you be a bit more specific? How does that happen? And what’s the fix for it?

If it is high resistance, replace the cable.

Riklimoguy · June 9, 2020

3 hours ago, Russ Swift said:

Just a thought, if yours is like mine. One push on radio just mutes the radio. Radio is still on the 10-15 minutes after engine turned off. Need to press and hold to turn off radio. Not sure if will add any useful info. In my past a battery problem was found to be a bad ground someplace on the vehicle. I’ll be watching to see how you solve this. Good luck.

Great point! I will try that! Thing is, brand spanking new Heavy duty Battery. You would think, even with the Radio on in the background, the stand by on that battery should easy handle that! Should handle at least 30-45m of standby power. This is my Third one, and boy is it drive me nuts. Never had any battery/Starting issues with the previous 2 Yukon’s! A 15’ and 17’ model.
had plenty other issues, lol. This is new for me!!
Had a friend Suggest that it could be a bad starter that’s doing the Drainage.. Honestly don’t even know if that’s even possible.. I’ll investigate it tomorrow.

I’ll keep you posted!

Edited June 9, 2020 by Riklimoguy

swathdiver · June 9, 2020

8 hours ago, Riklimoguy said:

Hi guys!
So here’s the skinny.. I’m stumped!
2018 Yukon XL SLT. 60k mil on it! A week or 2 ago, I started having my battery drained/dying on me randomly. I would start it in the morning with no issues whatsoever. Take a drive to the grocery store turn the car off, windows open, radio on!! Radio would turn off normally after 5m or so.. (Car completely off at this point) Before heading into the store, after playing with my phone for 20-30m, one day I decided to turn the car on after it had been at the stage described above!!
immediately the battery was spent, after a few similar episodes and begging ppl for a jumper.. I decided to put a brand new Battery, did that last Saturday! 2 days later back to do groceries, following same routine, as Described above, (thinking’ brand new heavy duty 200$ battery, nothing to fear, it happened again!! )

So I bring it it to my mechanic around the corner, does a quick test, says alternator bad, battery not getting enough charge!! Sooo In goes a new alternator.. All good! Amps solid! This morning woke up, car started fine, on my way home, stoped at Walgreens played with phone for 30m or so, then got out and into the store. 15min later get into the car, battery Dead again!! .
Two things I’ve noticed so far 1: if I park the car, and immediately exit, luck it up go about my business for 30/45/1hr or whatever when I get back, car starts immediately!
2: when I get home: exit the car, luck it up, car in the driveway 10/12 hrs, Car has no issues starting up immediately either.
I mean, what the heck is this? Some sort of short Circuit while I’m in the car and the car standing by, and car obviously unlocked?
Ignition issues?
Fuse issues?
Oh, and while Battery is drained, and car won’t start, every single electronic works inside.
im completely out of clues? I’ve checked for any sort of lights hanging on, nope! All off during the period described above!!

Any help would be greatly appreciate it!
Thanks, Rick!

Rick, something is not working right, probably something to do with the RAP system (Retained Accessory Power). The only way to easily and properly diagnose this is with a bi-directional scan tool. GM is using the MDI2 with GDS2 software on a laptop.

The stock battery has a reserve capacity of 110 minutes with a 25 amp draw.

Riklimoguy · June 10, 2020

2 hours ago, swathdiver said:

Rick, something is not working right, probably something to do with the RAP system (Retained Accessory Power). The only way to easily and properly diagnose this is with a bi-directional scan tool. GM is using the MDI2 with GDS2 software on a laptop.

The stock battery has a reserve capacity of 110 minutes with a 25 amp draw.

I see.. so pretty much have no choice but to bring it in at the stealer for a diagnostic? Any body else has a tool

like that? You know, trying to stay away from the stealer.. it’s a bit of a trust issue.. lol.

swathdiver · June 10, 2020

11 hours ago, Riklimoguy said:

I see.. so pretty much have no choice but to bring it in at the stealer for a diagnostic? Any body else has a tool

like that? You know, trying to stay away from the stealer.. it’s a bit of a trust issue.. lol.

Buy your own so you can diagnose it yourself. The scan tool will quickly pay for itself. Go to Chinacardiags to get an idea of what's available, some folks I know on other forums use the VXDIAG Nano with GDS software to work on their trucks. I use older Tech-2 which does not work on yours.

Russ Swift · June 10, 2020

Or find a garage you trust that already has the tools and diagnostic equipment to do the work. I agree, dealer is last/least desired option. Ask this forum for garage recommendations in your area, then rely on your own experience with any new garage. Even a tow and checkup at a good local garage will be less than any work at a dealer

Riklimoguy · June 10, 2020

29 minutes ago, swathdiver said:

Buy your own so you can diagnose it yourself. The scan tool will quickly pay for itself. Go to Chinacardiags to get an idea of what's available, some folks I know on other forums use the VXDIAG Nano with GDS software to work on their trucks. I use older Tech-2 which does not work on yours.

Was thinking exactly same thing. As a matter of fact, I already started looking. Thanks for the help buddy!!

Edited June 10, 2020 by Riklimoguy

Riklimoguy · June 10, 2020

24 minutes ago, Russ Swift said:

Or find a garage you trust that already has the tools and diagnostic equipment to do the work. I agree, dealer is last/least desired option. Ask this forum for garage recommendations in your area, then rely on your own experience with any new garage. Even a tow and checkup at a good local garage will be less than any work at a dealer

Yup. Great point. I do have obviously a few places in mind. Problem is been the aggregating factor thinking first that Battery was the culprit, then the freakin alternator. But the more i think and read about it. I’m convinced it’s gotta be the RAP System.
did a lil experiment this Mrng. I started the car for 15min turned it off, then immediately shut off the RAP MODULE by opening the Drivers door. Stayed inside the car fooling around on my phone exactly the same way I’ve been doin previously for about 30 more min. Guess what? The freaking car started like a well oiled machine. I mean, coincidence? Turn car off, stay inside with RAP ACTIVE, 15 min later, battery dead! So same exact thing with the only exception RAP off, Car starts immediately..

Thanks for the advise Brother!

Riklimoguy · June 13, 2020

On 6/9/2020 at 2:55 PM, It's Tim said:

Hi guy, just an update! So.. on Wednesday morning the car stared fine in the morning! Drove around for a bit, then drove home. Decided to do the test again, and let the car standby for 10/15 min while sitting in the car, next to my wife’s car.. Well... of course it died, again, so I said, ok screw it, I’m bringing it in to my guy in town.. Only problem, After trying to jump it, with my wife’s car, it would not badge!! . So figured it’s completely drained this time, call my neighbor across the street with his Ram to do a double Jump, he comes over, we hook him up as well, and to my surprise, NOTHING! He says I thing your Starter is Done! At first I question that, but after the guy gets under my car to bang it, he goes Stop, stop, stop.. There are sparks coming all over your starter, like firework type sparks

So after calling For a tow, was sitting there and wondering how the heck a starter with 60k on it goes bad.. ? And on top if it, causes all these havoc to have me change battery and alternator. Well, tow track comes, I bring it in, change the starter, Car starts instantly.. ! Can’t make it up..
Is it possible the starter started all this snowball effect? What are the chances the starter Draind the battery or killed the Alternator? (Which as i said earlier I changed a few days prior, thinking they were the culprit) I’m truly befuddled!!
So, not to drag it longer.. It’s been 3 days, car starts normally, I’ve tested standby 3 times, at 15m intervals, no issues! It starts right up. Cranks instantly!!
Only ominous sign is that the battery voltage hangs right around 12.8/13 volt constantly. With random spikes to 14 Volts! ONLY Exception, When headlights are on it spikes right up to 14 Volts within 30seconds or so.. truly bizarre.

fyi! BATTERY: AutoCraft Platinum AGM Battery, Group Size H7, 850 CCA

Edited June 13, 2020 by Riklimoguy

Russ Swift · June 13, 2020

If not actually the starter, may have been connections to starter, which were all secured correctly and tight with the new starter. You can only hope. Good luck and thanx for the the updates.

Still trying to figure out why my Rear Park Assist keeps going in and out. In the process of checking three fuses and one relay to see what happens. If it is on when I start up, it goes out after driving a short time. Makes me think something heats up and causes a short to the system. No rush to go to the Stealer/Dealer.