Flashing warning light but no message

And yet another problem with this vehicle. Got in started ok, backed up, turned around, put in drive the warning light, the yellow triangle with the exclamation starts flashing and beeping. I stopped, looked for messages, nothing. Put it in Park, lights goes off. I got out checked around vehicle, saw nothing, put it back in drive light flashes again. Again put it in drive, goes out get out check again see nothing, put it back in by drive, this time no light. Has this happened to anyone else? Transmission or other drivetrain issue?

 

When back door was not closed all the way.

 

Check to make sure your parking brake is fully released.

 

Thanks for suggestions but the brake was released; the back door had not been opened on the trip.
It is weird. There was no "break on" or "door open" or other issue accompanying the flashing warning light. I guess it was a malfunction

 

In May 2022 I replaced a relay because the vehicle would not start. I have to several issues over recent weeks that make me nervous the same relay, or another one, is going bad. I'm to the point I don't like driving it very far from hone

 

Your hood is open.

 

Not an open hood. I drove the truck earlier and did not open the hood. The light went out but I did not check anything at the hood. I think it must be a malfunction. This, along with other recent issues, makes me think a relay or other computer related component is about to stop working

 

This is very possible. If the hood latch is sticky or broken it can cause this.

 

The light went out but possibly something in the hood latch. If it comes back on I will check that. As I noted there was no message with the light just the yellow triangle warning light flashing along with a buzzer..but no message indicating what the issue was. That is why I'm thinking a malfunctioning light

 

Would be helpful to know what trim level and what options your truck has, including cab size. What aftermarket add-ons as well. Your profile only says 2019 Tundra and there’s a number of variations in the different electrical systems for that particular year based on trim and cab

 

Are you on the original battery still?

 

When the hood is unlatched there is no message, just the blinking triangle and beeps, it goes away when it park, only comes on while moving.

 

That is what happened. I will check the hood latch but I have not opened the hood for a week or so and be the light finally went off

 

I don't know. I bought the vehicle used. Probably not. The vehicle has 55k miles and is approx 4 years old

 

It is a 2019 double cab. Few options. It has satellite radio, and Bluetooth, but no gps, few other options.
I really think it is a malfunctioning warning light. I drove the truck to lunch. No issues on way there. After lunch the flashing warning light came on as I pulled out of parking lot. I pulled into a parking space put tranny in Park, light goes out. I got out, looked around vehicle but saw nothing obvious. Put in drive again, again light flashes. Put in Park get out, nothing. Get back in, once again in drive no light. Drove home with no issue. I have had problems with transmission "jumping" when shifting into drive so it may be a transmission issue but I'm thinking a malfunction.

 

Thinking about it the transmission "jumping" occurs when turning around in a parking lot..just like the warning light issue. Maybe I should avoid parking lots lol

 

I've seen some weird things happen when batteries start to fail.

Is the transmission "jumping" only when going from P to a drive gear? I've always noticed somewhat of a lurch when going into gear. I guess doesn't explain the light though.

 

Have you brought it in somewhere to pull codes? My experience is that there are rarely “malfunctioning warning lights” and more often other malfunctions (sometimes intermittent) that cause warning lights…

Dying batteries
Faulty grounds
Damaged wires (rodents, or many other causes)
Hood latch sensors
Fuel tank caps not fully tight
A door latch sensor not fully engaged or failing
A transmission position switch failing
The list goes on…

The light is simply an output of an issue condition…The source of the issue is the challenge to find

 

Unfortunately you typically will not pull any codes without a CEL.

 

Possibly
I’ve seen codes from other systems that don’t trigger CEL like the AC systems and occupant sensors in newer vehicles.
It’s worth at least checking

 

Thanks for the suggestion. It is worth checking. When I said the warning light was malfunctioning, I should have said the computer system is malfunctioning. I have already had to replace a relay that prevented the vehicle from starting. I also posted about the transmission "jumping" when going from R to D - when backing from a parking space for example. I took it to a dealer but they could find an issue with the transmission. I'm concerned both are part of a bigger computer issue