2020 Limited Key Fobs Issue - Stopped Working Suddenly

Alright running into a very odd issue. Traveling currently so limited on time to give up the vehicle until I get back home and have an appointment scheduled. Curious if any of y'all have run into this before.

2020 Toyota Tundra Limited w/ Offroad package

Issue: Key fobs (2 - 1 daily use & 1 backup) suddenly don't succeed in locking/unlocking/remote starting/alarm functions.

Symptoms noticed & troubleshooting steps taken:
- All Smart Lock functions with the truck are successful
- Doors lock and unlock with the smart key door handle functions.
- Key fob detected for starting vehicle without having to be right on push-to-start button
- Dome lights turn on as you approach the vehicle
- Unable to lock truck manually with key while key fob is placed on center console of truck (expected as to prevent locking the keys in the truck)
- Remote Connect functions as expected - Lock/Unlock Remote Stop through app works.
- When truck is started via Remote Connect in the app, if I attempt to use the key fob to unlock, truck will turn off as though the signal is being received but doors will not function to unlock.

Steps taken for troubleshooting:
- New batteries in both fobs. No change
- Attempted modifying settings in Door Lock settings in Head Unit. No change
- Attempted cab discharge x2 by disconnecting both +&- battery terminals with at least 15 minutes passing before reconnecting. No change
- Saw other forums for Key Fobs not responding due to dome light changes from halogen to LED (not relevant to my issue) since the key fob receiver is on same circuit. No issues with fuse or dome lights. No change.
- Checked ECU ACC fuse as another culprit of this type of issue. No issues & no change.
- Checked other fuses somewhat at random but found nothing blown.

Stopped by local Toyota quickly to see if they'd heard of it before but Service Foreman hadn't had this specific issue before. Did state that it's believed the 2020 model has two receivers for Key Fob functions. 1 for Smart Lock functions (hence why those seem to all be working) and 1 for regular key fob functions like the ones not working.

So with all that, if you've made it this far, any thoughts or solutions?
Thanks!

 

RESOLVED!!!

After trying a few other things without getting anywhere, I started searching forums more intently and broadened the scope of search terms.
With that, I found a thread that depicted almost exactly the same issue.

Here is the thread if interested https://www.tundras.com/.../fob-not-working-after.../...

Seems as though it is a rare glitch that when adjusting settings in the Door Lock controls in the settings on the head unit, this can cause the wireless fob setting (which is only available through OBD2 port and Toyota techstream/3rd party customization controls) gets flipped from on to off.

Stopped back by the Toyota dealership on my way back through town and asked them to check if this setting was actually off. The service foreman said he'd never seen it before but that was indeed what was causing the issue.

Glad I found the forum before tearing into unnecessary investigation steps.

 

I'm having this exact issue right now and can confirm I was tinkering with the head unit settings (decreasing the volume of the beeping). The head unit was being weird... I would change a setting and it would revert back to what it was before. I finally got the change to take/hold and immediately after that the issue you described started.

So the solution is to have Toyota get in there with their OBD2 tool and flip the setting to 'On'? Will they know what I mean when I ask them to turn the Door Lock controls back on? Did they charge you anything?

 

It was resolved by going to Toyota and having them re-enable the remote lock/unlock settings with them connecting to the truck via the obdII port and using TIS/Techstream (their service program)

When I went in, it took some convincing that this should be the fix but I essentially bet that if it wasn’t the fix, then I’d leave. 10 minutes later the head tech came back and said it was the solve and sent me on my way without charge. I could see a world where they would charge for a diagnostic fee but if it were me I would try to negotiate that. Handing them the fix (if that’s what it is) and getting charged doesn’t sit well since it literally will take 5 minutes.

Best of luck!

 

Got it, thank you! My buddy has an auto body shop, so I’ll take it there tomorrow to avoid the dealership if at all possible.

 

I am having the same exact issue. I have the AJT fob but it worked fine for months, besides the lights blocking the sensor, but once the lights went off i could lock it no problem. Then one day I went and started changing some settings because something annoyed me and then boom, cant lock or remote start. Tried new batteries in the fob, tried messing with the head unit for entirely way too long, i think i'm going to disconnect the battery and see if that resets it. If not, i guess i'm going to Toyota, i'm due for maintenance anyways. Thank god i found this thread though, i made an account just to say thanks. I've been lurking on the site for a while now but never felt the need to actually post. This has caused me such a headache though that i couldnt not say thank you. You Da MAN.