8.4" to 12.1" screen replacement

[MannyN]

I actually did both. I have the adapter harness which is wired correctly, but just to double check it I re-pinned the harness on the truck itself. Same result, the buttons on the surround work fine, but the screen won't power on and the volume/tune knobs do nothing (no sound from radio at all).

Well then, you did everything correctly and should work. Time to file a claim and return the unit to seller. Sorry.

 

[Infotainment]

Hey all - so I'm in need of a bit of help. I have a 2021 Ram 1500 Laramie with the 8.4 non-nav UC4 from the factory. I picked up a 12" UC4 setup on eBay from a guy who pulled it from his 2020 1500 and swears it was working when removed.

Long story short, I have everything wired up (all harness cables from the truck and the LVDS cable from module to screen) and made the changes to ICS (not enabled) and DCSD (enabled) in AlfaOBD. I have double and triple-checked the wiring, even re-pinned the HVAC harness to be sure it wasn't a bad adapter. All the buttons on the surround work (A/C, hazards, etc) but I get nothing from the screen and no sound from the radio. Just black screen of doom.

I pulled fuses F41 and F44, tried pulling the negative terminal on the battery and left it for over an hour, power cycling the truck, and resetting the ECU in AlfaOBD to no avail. I'll list the parts below in case anyone knows something I don't. Dude swears it works, but I'm starting to think I need to submit a claim on this thing.

Module: 68378392AB
Screen: 68312620AG

I know the module is from a 2500, but from everything I've read in the forums folks swear it works in a 1500. If somebody knows different, let me know!

Sounds like your UAX module is bad. With no sound at all then I'd have that checked out. We can do a bench test on all components or just the module if you like to go that route. HD UAX should work just fine in a DT, only issue can be cargo camera and/or steering wheel controls, it shouldn't stop the unit from displaying anything. If your programming is correct, you can double check it by performing a canbus reset which will allow the UAX to display image for one cycle. Since you did this and still have black screen then again its the UAX module.
Feel free to reach out to our sales team for a bench service if you want to know for sure.

Advisor Team
Toll Free — 1-855-636-6287
Open a Ticket with our Team

 

[Shadowsnkx]

Seems that I can find every sw version but 39.7. Does anyone have a link for it? Anyone successfully downgrade?

 

[Infotainment]

Seems that I can find every sw version but 39.7. Does anyone have a link for it? Anyone successfully downgrade?

39.7 was unreleased as it was riddled with problems. There is a 39.9 for the UAX but its best to just go to 40.1 as its the last update for all Uconnect 4s including the UAX 12" system.

 

[Shadowsnkx]

39.7 was unreleased as it was riddled with problems. There is a 39.9 for the UAX but its best to just go to 40.1 as its the last update for all Uconnect 4s including the UAX 12" system.

Looks like anything after 39.7 looses performance and off road pages.


Sent from my iPhone using Tapatalk

 

[theRamguy]

finally got my files back Update PR39

 

[DFWCook]

Is it possible to swap a 2019 Uconnect 8.4 with Nav for a 12" with nav and keep the function of the CD Player & LTE Wi-Fi in the truck?

I would like to do a UC5 to have Wireless CarPlay but staying UC4 is fine.

 

[theRamguy]

Is it possible to swap a 2019 Uconnect 8.4 with Nav for a 12" with nav and keep the function of the CD Player & LTE Wi-Fi in the truck?

I would like to do a UC5 to have Wireless CarPlay but staying UC4 is fine.

Yes. I had the 8.4Nav and did a full swap. I had to get in touch with the Uconnect engineers but I was able to use remote start, WIFI, and Ram Connect