Battery dying every night, RPM fluctuation after jump start, temporary loss of power

[AN292]

Recently my Tahoe has been dying overnight, 3 nights in a row.

Once I jump it, the RPMs will fluctuate up and down from 500 to 800. I’ll put it in drive and give it a little gas but it’s underpowered. Upon releasing the gas, it has this slightly aggressive RPM drop and you can feel the loss of power/mild jerk.

This goes away after a little bit of normal driving.

I’ve pulled codes, and they are also attached below.

A couple points. The alternator and battery are only a few months old.

I cleaned the MAF 2 days ago, and I also did that little toothpick trick for the ignition switch harness in the steering wheel area. I made sure the throttle body harness is connected and I also never touched the TB or butterfly valve.

I also have the following connected to my battery and it could be why it’s dying.

• A front and rear dash camera
• Viper alarm
• Exhaust cutout

Thanks for the help

 

[Jason in DLH]

Happened to me recently, then I realized the dash lights and radio stayed on the entire time after shutting the engine off. After fixing a few other problems the radio and lights thing kind of went away and is working almost perfectly again. I use a battery tender now.

There’s a good video about testing each fuse to see if it has constant power to it. I’ll try and find it again...

 

[Fless]

After you turn off the truck and remove the key from the ignition, turn the radio on. When you then open the door to get out, does the radio turn off?

You'll want to check the electrical system for parasitic draw. Eric O has a couple of good videos I'll link below, but there are numerous others out there. Perhaps you can narrow down which circuit is causing the draw. I'd be interested in knowing what you find.

I'm currently dealing with an intermittent draw in mine. I don't have the alarm and dash cam, and once all of the modules in mine go to sleep the draw is around 25ma. My occasional draw is around 1.5a, so it's quite a bit. But I have yet to catch it when it happens again so I can diagnose it. Right now I'm just watching it after each shutdown.

I have the automatic climate control that draws about 40ma and takes around 3 hours to completely shut down, and that is normal.

The gauge clusters in these are also known to have a parasitic draw if there is something wrong with it. They call it silver migration on the circuit board.

Your U-codes indicate an issue with communication; for the DDM you may want to check the harness at the front of the driver's door, where the wires go into the body. They can break there, underneath the insulation. So the wire might look good but could be broken inside.

 

[AN292]

After you turn off the truck and remove the key from the ignition, turn the radio on. When you then open the door to get out, does the radio turn off?

Yes it does. I forgot to mention I have a 7" Sony screen in there. It does shut off when the door is open although there have been times where it has stayed on and it required that I open/close the door a ton of times or start the truck again and turn it off.

 

[Fless]

Yes it does. I forgot to mention I have a 7" Sony screen in there. It does shut off when the door is open although there have been times where it has stayed on and it required that I open/close the door a ton of times or start the truck again and turn it off.

I updated my post, so take a look at those videos.

Having to close the door multiple times to get the RAP to shut down indicates a probable malfunctioning door latch / actuator.

 

[Jeff Shriner]

checking for parasitic draw is very important. buttttt i recently purchased a 2006 denali yukon xl, high mileage but everything worked with the exception of the 6 disc cd changer and the rear window wiper. did some digging and found two broken wires for the rear wiper and missing fuse for 6 disc changer and boom all good. next morning vehicle is dead like dead dead, so i jump start and thinking i had it on and not running the day of repairs and had to jump start it the battery was 4 yrs old i went and got a new battery. next day dead again. so ok i did parasitic draw and had very low like less than 50 miliamps and that was with the remote start / alarm plugged in. long story short the fuse for 6 disc changer is out and battery does not drain. but it did not change the parasitic draw by removing that fuse so something was making a parasitic draw sometime after the 15 minutes that i tested. i am ok with no 6 disc changer so no big but as a last resort you could check that. i have traced many system amp draws in the past i am quite accomplished at it but this one puzzled me.