Brake lights are not working He has replace the brake on/off switch and checked all the fuses

Hello,

This sounds like a wiring issue. Likely bad ground.
The ground connection on these vehicles can corrode and the lights will not function.

Here is a helpful guide on how to check wiring:

https://www.2carpros.com/articles/how-to-check-wiring

I have attached the wiring schematics for the lights for your reference.

Please let me know of any questions.
Thank you.