Tail light indicator light on dash

Hello everyone,
I am new to owning a taco and to this forum.
With that out of the way I need some real help, I have a 2006 Tacoma that has a very annoying issue. The tail light indicator light, the image below is a light that is blinking on my dash and I can't get it to stop for anything. I need help with figuring out why its blinking and how to make it stop properly.
Things I have tried
Replaced all bulbs in the rear of the truck including tail and brake lights, license plate lights and blinkers
Replaced battery thinking it was a voltage issue or such
I'm wondering what causes the dash light to come on in the first place? Cause if all my taillights work and the light on the dash is still blinking something else is the issue. I was wondering if anyone has had this similar issue and if you could help me out, please.

Thank you,
David

 

Update I was driving the other day and out of no where the light turned solid anyone know why it would be blinking then go solid?

 

So now it's working like it should...Canadian model Tacoma.

 

I'm not sure if it is working the way that it should however, it's not blinking anymore. The reason I say this is because if I remember right its only suppose to come on when you have your headlights turned on as it is a tail light indicator, not a brake light indicator. That being said it is staying solid all the time even when all lights are off and the car is first started.