High Idle

JW2024 · August 27

I have a 2024 Sierra 2500 AT4X with the Duramax. I would like the high idle feature installed. I know it’s dealer programmed and I called several in the area that had no idea what I was talking about. I found a dealer locally that had my truck for 2 days and said the truck would not take the program. Anyone have any suggestions? I live in Fort Worth, TX.

Another JR · August 27

1 hour ago, JW2024 said:

I have a 2024 Sierra 2500 AT4X with the Duramax. I would like the high idle feature installed. I know it’s dealer programmed and I called several in the area that had no idea what I was talking about. I found a dealer locally that had my truck for 2 days and said the truck would not take the program. Anyone have any suggestions? I live in Fort Worth, TX.

I would suggest calling GM tech support and ask them to assist your dealer. If high idle was an available option in your truck trim level (it was), I believe it can be turned on with a software switch. I suspect the dealer was trying but was not doing the procedure correctly somehow.

Did you try it to make sure they didn’t succeed? If the person tries to turn it on with their foot on the brake it won’t engage. Engine running, in Park, parking brake on, feet off the pedals, momentarily move the cruise control paddle switch on the steering wheel down to the set position.

JW2024 · August 27

Thanks JR. The service advisor said the tech had assistance from TechLine. Said the remotely connected in to their computer to try to help but no luck. I did have to pick up my truck because I needed it. Maybe more days there would have helped.

I have tried to activate it but no luck.

redwngr · August 27

The technician probably has all this.

https://www.gmupfitter.com/wp-content/uploads/2021/06/UI-Bulletin_82h-1.pdf

redwngr · August 28

Are you looking for higher speed for accessories or engine warming in winter?

JW2024 · August 28

The tech did have the bulletin. I emailed it to the service advisor and he printed it out for the tech.

Higher speed for accessories. I know about the enhanced heating setting for winter and it works great.

I did call another dealer today and the first advisor they connected me to had no idea what fast idle was. He got a “senior” advisor. The then went to ask their diesel mechanic. The mechanic said they could do it and told him the steps in the bulletin. At least it sounds like he knows what to do. I have an appointment next week to get it done.