Auto shut off

Ernest Crist · October 18, 2021

My 2020 RST 6.2 will shut off automatically, which it should, but as I’m still waiting for the light it will come back on. Or a lot of time it won’t shut off at all

redwngr · October 18, 2021

That's what it's supposed to do.

There is a limit to how long stop/start will stay off.

There is a long list of things that will prevent it from stopping, or will restart before the timer.

pg 232 in the '21 sierra ON

Auto Engine Stop/Start

When the brakes are applied and the vehicle is at a complete stop, the engine may turn off. When stopped, the tachometer displays AUTO STOP.

See Tachometer pg 109.

When the brake pedal is released or the accelerator pedal is pressed, the engine will restart.

To maintain vehicle performance, other conditions may cause the engine to automatically restart before the brake pedal is released.

Auto Stops may not occur and/or Auto Starts may occur because:
. The climate control settings require the engine to be running to cool or heat the vehicle interior.
. The vehicle battery charge is low.
. The vehicle battery has recently been disconnected.
. Minimum vehicle speed has not been reached since the last Auto Stop.
. The accelerator pedal is pressed.
. The engine or transmission is not at the required operating temperature.
. The outside temperature is not in the required operating range.
. The vehicle is in any gear other than D (Drive).
. Tow/Haul Mode or other driver modes have been selected.
. The vehicle is on a steep hill or grade.
. The driver door has been opened or the driver seat belt has been unbuckled.
. The hood has been opened.

. The Auto Stop has reached the maximum allowed time.

bdallas · October 18, 2021

Completely normal.

There is a whole checklist of items that have to be in line for the auto shut off to activate in the first place. Then it can only stay off for so long. If your air conditioner is on, it will stay off for about half a minute. If the AC is off, it might stay off for two minutes.

...just like redwngr said.

Edited October 18, 2021 by bdallas

Ernest Crist · October 18, 2021

Thank you guys for the information. It’s very helpful and reassuring. I love my truck. I found a used Rocky Ridge edition for a very good deal. It had 25000 miles and only 1 owner. It would suck to think it has issues already.

Greg Peak · October 21, 2021

Put on e- brake.Put Truck in neutral .Engine will stay running till it runs out of gas.. 2019 1500

redwngr · October 21, 2021

12 minutes ago, Greg Peak said:

Put on e- brake.Put Truck in neutral .Engine will stay running till it runs out of gas.. 2019 1500

Pretty sure OP was asking about the 'auto stop/start' at a light, not about it shutting off when idling in park.

(although that question is frequently asked as well....)

Edited October 21, 2021 by redwngr

23 Silverado · August 26, 2024

Anybody know how to disable the idle shut down. Not the automatic start stop, the 15 minute idle timer.

L Morgan · August 28, 2024

On 8/26/2024 at 8:21 AM, 23 Silverado said:

Anybody know how to disable the idle shut down. Not the automatic start stop, the 15 minute idle timer.

Wondering the same myself but know this wasn't original question. The manual says engine shuts off after :15. Would like to have it go longer so if I'm on a trip with my dog and I stop for a quick bite to eat I'd like AC to keep running a little longer. Will try e-brake on suggestion.

cubsfaninsc · September 5, 2024

On 8/28/2024 at 8:51 AM, L Morgan said:

Wondering the same myself but know this wasn't original question. The manual says engine shuts off after :15. Would like to have it go longer so if I'm on a trip with my dog and I stop for a quick bite to eat I'd like AC to keep running a little longer. Will try e-brake on suggestion.

To disable the 15 minute auto shutoff, do the following.

When starting your truck, press AND hold in the start button for about 10 seconds. Then release. You will see a message on the dash that auto shutoff has been disabled. It will be disabled until the next time you shut off your truck. I do this everyday, while I am waiting for my soon to get out of school, so I can have the truck and the A/C running while I wait for him.