cause of brake light and abs light and traction control light remaining on?

Hello,

The ABS light gets triggered when the on-board diagnostics detects any fault within the system. It could be due to a wheel speed sensor, wiring issue or faulty module.
Usually ABS, traction control light gets trigger for the same reason.

https://www.2carpros.com/articles/abs-warning-light-on-easy-repair-guide

A good first step would be to scan and retrieve the ABS fault codes. This can help with the diagnostics.

Here is a helpful video of how to get those codes:

https://youtu.be/rTtAnsOlZU4

Please let me know what code(s) that you get.

Thank you.