2016 Suburban Aux Ports Blink Off

[Clint Casanova]

My 2016 Suburban’s auxiliary ports and features (USBs, wireless charging pad, 12V) blink off briefly when the doors are shut while cranked. This can cause my aftermarket headrest monitors to power off and back on if I get out of a cranked car to pump gas, hand a kid something in the back seat, run into gas station or restaurant, etc. This is extremely frustrating on road trips, making a pit stop and having to turn the TVs back on, DVD player back on, etc. 

 

Sometimes if the key fob is left in the car it won’t blink off, but not always. Every time this happens I hear a click, like a light blinking, behind the dash as the door is closed. What is happening back there, triggered by the door closing, that’s causing a sudden loss of power to so many auxiliary items? 
 

Attached video shows what happens to a cranked car when the door is closed with fob outside the car. I have a Blu-ray player, wired into a wire in the dash labeled for the BCM, but several other items have the same reaction to shutting the door while cranked with fob outside. 
 

Much thanks. 

[SARNCAN]

My 2016 Suburban’s auxiliary ports and features (USBs, wireless charging pad, 12V) blink off briefly when the doors are shut while cranked. This can cause my aftermarket headrest monitors to power off and back on if I get out of a cranked car to pump gas, hand a kid something in the back seat, run into gas station or restaurant, etc. This is extremely frustrating on road trips, making a pit stop and having to turn the TVs back on, DVD player back on, etc. 
 
Sometimes if the key fob is left in the car it won’t blink off, but not always. Every time this happens I hear a click, like a light blinking, behind the dash as the door is closed. What is happening back there, triggered by the door closing, that’s causing a sudden loss of power to so many auxiliary items? 
 
Attached video shows what happens to a cranked car when the door is closed with fob outside the car. I have a Blu-ray player, wired into a wire in the dash labeled for the BCM, but several other items have the same reaction to shutting the door while cranked with fob outside. 
 
Much thanks. 

I guess you have a bad battery that needs to be replaced, otherwise check the terminals if they are not tinted well or not clean.

[cs15dah]

Newer cars turn off power to accessories during cranking so a sudden power spike doesn’t damage whatever is on the circuit. This is normal operation. 
 

if you truly want an always hot +12VDC, recommend running a wire from your battery, through a *fused* terminal block, and into your passenger compartment, where you can tap into it with all the electronics you want to keep powered up during your fuel stops. Just don’t forget to switch those items off when you stop and leave your vehicle for an extended period of time. Lest you drain your battery because a DVD player was left running overnight. 
 

Lots of good resources online on how to construct said circuit, if you’re semi experienced with electronics. Otherwise, you should seek professional help. I like the12volt.com. Great source for information. If you go this route, good luck! Hope it comes out exactly how you want it. And for Pete’s sake, don’t catch your vehicle on fire!!

[Clint Casanova]

7 hours ago, SARNCAN said:

 

I guess you have a bad battery that needs to be replaced, otherwise check the terminals if they are not tinted well or not clean.

 

Doubt it’s the battery, as nothing else is demonstrating any battery issue. Also, it doesn’t happen if the key is in the car when the door is closed. It’s something to do with the key being detected, at least some of the time. 

[Clint Casanova]

3 hours ago, cs15dah said:

Newer cars turn off power to accessories during cranking so a sudden power spike doesn’t damage whatever is on the circuit. This is normal operation. 
 

if you truly want an always hot +12VDC, recommend running a wire from your battery, through a *fused* terminal block, and into your passenger compartment, where you can tap into it with all the electronics you want to keep powered up during your fuel stops. Just don’t forget to switch those items off when you stop and leave your vehicle for an extended period of time. Lest you drain your battery because a DVD player was left running overnight. 

To your first point, that’s not the issue. Remember, the car is cranked already, running normally, all things functioning as they should, and the door is opened and then shut with the key outside the car, and this causes the power to auxiliary sources to cycle off and back on, along with the chime. So, it’s not a normal function during cranking, as that may have taken place seconds, minutes, even hours earlier. 
 

As for hooking to constant power, I don’t want the responsibility of remembering to turn things off. I know that’s an option, but I’d prefer to figure out why this is happening so I can fix it.

[BlaineBug]

I believe there is a fuse somewhere that can be MOVED to keep constant 12 volts at the auxiliary ports, versus "ignition only" power.

I am NOT sure if this applies to the USB ports as well, however.