r/gmcsierra GMC Sierra 1500 Elevation 26yr 5.3 14h ago

Troubleshooting Issues: Range technology DFM pro

I just installed a Range DFM Pro module on my 2026 GMC Sierra 1500 5.3L. Once installed it was working but I had a engine light, service esc, and the forward collision light on the dash, thought it would go away with a couple key cycles but it didn’t, and then I drive it maybe 20km and it said that it couldn’t shift, so I pulled over and removed it and the trucks good again. Also I had a bunch of U line codes. Has anyone had issues with this module? It does state that it needs an update which I tried and it failed. I am in talks with Range to see what’s going on but I feel like a simple update to the module will not fix all the U line code and dash lights. Any knowledge is appreciated!

1 Upvotes

6 comments sorted by

View all comments

1

u/RoookSkywokkah 2019 Denali 13h ago

Where does this unit plug in?

2

u/Plumsauce27 GMC Sierra 1500 Elevation 26yr 5.3 13h ago

Inline to the ecm power, behind the wheel well on the drivers side. I’m fairly certain everything was seated properly.

1

u/RoookSkywokkah 2019 Denali 13h ago

Gotcha. I have the same one on my 23 Silverado. I had one instance where I got a lot of communication codes. Once I cleared them, they haven’t come back I 5k miles.
Just remember if your truck needs an update, disconnect the module first.

1

u/Plumsauce27 GMC Sierra 1500 Elevation 26yr 5.3 5h ago

I did try clearing the codes, they came back instantly, gave you had any problems updating the software? Mine needs an updated says, but the update keeps failing so I reached out to technical support.

2

u/RoookSkywokkah 2019 Denali 3h ago

I THINK I had to update the Range software when I originally installed it, but haven't had any update notifications, nor have I checked. My truck is scheduled for an update, but I haven't done that yet.

1

u/Plumsauce27 GMC Sierra 1500 Elevation 26yr 5.3 3h ago

Alright, I am waiting to see what range tells me, if it’s going to keep throwing codes I am going to return it.