If you received a written warning in Texas than it should not go on your driving record and thus would not be seen by your insurance company for it to affect your rates. Convictions of moving violations go on your driving record but not written warnings in Texas so your offense of not yielding at a light should not be released to your insurance company.

States handle written and verbal warnings differently but from what we have read in Texas they issue written warnings due to the need to keep statistics and show they are not racial profiling drivers not to place it on your driving record. Also there may be a local database that the warning information is inputted into that TX Troopers or other law enforcement officers can see so if you are pulled over again they will know you already received a warning for other this offense and it may help determine if you get a warning or an actual ticket.

As you noted your warning doesn't come with any fee or fine to pay and it also does not go on your Texas motor vehicle record (MVR) so neither your insurance company nor employer would see that you were stopped and warned for committing this offense.

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