Seatbelt Light and Dome Light Come On While Driving

Is the car salvaged title?

 

As often happens, diagnosis over the internet is always a huge degree of blind guessing.

But if it is happening while driving or when hitting a bump my first reaction would be to suspect a door latch isn't closed tightly.

But that wouldn't explain why the seatbelt light would flash...assuming you are wearing your seat belt at the time.

My suggestion...as a rudimentary first step is to make sure all your doors and hatch are firmly and securely closed. And also make sure your seatbelt is clicked in good.

Quite frankly it's probably NOT going to be that simple an answer, because the universe is rarely that kind. But that's a cheap enough and simple enough first step on the way to further diagnosis.

 

Loose wiring harness beneath the seats (seat belt continuity), loose door microswitch (dome light).

 

That's what I was leaning towards with the dome light.

But since the OP reported that the vehicle doesn't have a history of a wreck or body shop rebuilding the idea that you would simultaneously have a door switch go bad...at the same time a wiring harness beneath the seats would go bad? Seemed like beating the odds.

I was trying to find ONE thing, that would account for both symptoms, since they seemingly both manifested at the same time.

 

How long have you owned this car? Was the car purchased from a Toyota dealer?

 

The seat harness plugs often get jostled by items placed underneath the seats. I have had door switches (plunger or micro) fail randomly.

 

Another probably more remote possibility is rodent damage to the wiring harness. That would involve a bit of snooping around under and inside of things. Potentially difficult to find. There are usually other telltale signs, like various leavings here and there, but if the car was cleaned up for sale they would likely have been removed.