No option to change from dark to light theme

[Rado]

Glad I DO NOT have Nav on my 2015 SLT
I use my Garmin for years
And use the Garmins in my service truck daily for many years and it never failed me !
Traveled cross country on my motorcycle several time with a Garmin !

On my Hyundai Elantra their system is also spot on

 

[JKH5199]

I tried Jimmy's advice and unfortunately it didn't work for me either. Still have the issue and dealer is no help saying that it's working as designed. They refuse to acknowledge the issue.

 

[RamDiver]

I tried Jimmy's advice and unfortunately it didn't work for me either. Still have the issue and dealer is no help saying that it's working as designed. They refuse to acknowledge the issue.

If you're determined to find a solution, you could learn how to use AlfaOBD to tweak the BCM.

There could be a solution in there but you will be exploring uncharted territory.

A successful connection will be a learning experience too.

@Ken226 has had some success.

.

 

[Dome11]

All,
I'm a bit late to this thread however, I have been closely monitoring all the input. I have a 2026 Rebel with all the electronic goodies. Purchased new about 5 weeks ago and I have had the day/night screen mode (and now the SiriusXM radio) issues from day one. I have tried the soft/hard resets, headlight auto/manual trick, even removed the battery connection. The issue will resolve itself each time I perform on of these functions but returns after 2 to 5 ignition cycles. At least the dealer acknowledges the issue and has ordered a new radio. Now, I will proceed cautiously but for the heck of it I put the symptoms into AI just to see the response. Disclaimer: I no way do I suggest this is a solution this is just to add (hopefully) meaningful subject matter to the discussion.
According to AI:
Your 2026 Ram Rebel uses three modules to decide whether the navigation screen should be in day mode or night mode:

BCM — Body Control Module​

Controls:
Headlights
Ambient light sensor
Auto‑dimming logic
Interior lighting

TBM — Telematics Box Module​

Controls:
GPS
Time
Location
OTA updates
Ambient light data pass‑through

HMI — The Uconnect 5 head unit​

Controls:
The actual screen
The map renderer
UI theme switching

**ISSUE

The BCM is sending correct day/night data…​

…but the TBM intermittently stops forwarding that data to the HMI.**

When the TBM stops talking, the HMI defaults to:

Night mode, low brightness, dark map.

Because from the HMI’s perspective, it’s “dark outside.”

The fix you actually need​

You need the dealer to perform:

TBM Software Update / Reflash​

AND

HMI Update (if not already done)​

The TBM update is the critical one.

 

[Garr]

Same issue here. The first display died and dealer ordered new display. Old display had the theme mode replacement does not. At the dealers again for overnight battery disconnect. Here is what engineering told the dealer to do

Vehicle: 2026 RAM 2026 1500 Rebel Crew Cab 4X4 Requested Repairs/Services:​

1 - as per engineering-customer has several raio concerns-- please try performing this procedure > perform overnight battery disconnect. Then go into the Radio settings menu, select the Reset menu, From the Reset menu perform a Clear Personal Data Routine. After the CPD has completed, perform a Restore Vehicle Configuration using the WiTech. After the Restore Vehicle Config has completed, make sure there are no devices plugged in to the USB ports and that the ports are clear of debris. Then move the vehicle outside in clear view of the sky. Delete all the user profiles except Driver 1. Then perform Factory Reset -- Go to apps--> Settings-->Reset-->Factory Reset. Start the vehicle and let it run for 30 min. Let me know what happens. Thanks.​

 

[RamDiver]

Same issue here. The first display died and dealer ordered new display. Old display had the theme mode replacement does not. At the dealers again for overnight battery disconnect. Here is what engineering told the dealer to do

​

Vehicle: 2026 RAM 2026 1500 Rebel Crew Cab 4X4 Requested Repairs/Services:​

​

1 - as per engineering-customer has several raio concerns-- please try performing this procedure > perform overnight battery disconnect. Then go into the Radio settings menu, select the Reset menu, From the Reset menu perform a Clear Personal Data Routine. After the CPD has completed, perform a Restore Vehicle Configuration using the WiTech. After the Restore Vehicle Config has completed, make sure there are no devices plugged in to the USB ports and that the ports are clear of debris. Then move the vehicle outside in clear view of the sky. Delete all the user profiles except Driver 1. Then perform Factory Reset -- Go to apps--> Settings-->Reset-->Factory Reset. Start the vehicle and let it run for 30 min. Let me know what happens. Thanks.​

Thanks for the report.

And welcome to Ram Forum.

.

 

[olyelr]

My 2026 big horn was set on the day/night setting when i first got it. It was wayyyyy to bright for me when it was white, even during the day. So i switched it to black permanently. Never had a problem seeing it during the day with it black.

Now you got me curious if the option for my radio is gone now too. Might have to look haaa.

 

[RamDiver]

My 2026 big horn was set on the day/night setting when i first got it. It was wayyyyy to bright for me when it was white, even during the day. So i switched it to black permanently. Never had a problem seeing it during the day with it black.

Now you got me curious if the option for my radio is gone now too. Might have to look haaa.

I keep all my devices on dark mode, because I find white mode is too hard on the eyes.

.

 

[rossn2]

Brand new 2026 ram Bighorn and mine is same way. The theme button is missing and dealership is stumped also. 680 miles on truck.. have rebooted system numerous times and doesn’t fix issue. Ram customer service is useless

 

[RamDiver]

Brand new 2026 ram Bighorn and mine is same way. The theme button is missing and dealership is stumped also. 680 miles on truck.. have rebooted system numerous times and doesn’t fix issue. Ram customer service is useless

This must be the Uconnect/Atlantis Syndrome (UAS).

Please update your avatar details. TIA

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