1. When I am reversing the car rear sensor sound is not coming. How can we enable it.
2. When I drive on 120 kmph on display it alrming in red that on display. How can I also enable sound of alarm.

Hope somebody can help me.

 

1. Do you have obstacle when reversing? If not, it shouldn't sound. If yes, then something is faulty.
2. Do you have a picture? Difficult to understand what is meant.

 

"Yes, I encountered an obstacle while I was reversing; it was just 1 inch away.

Actually, the owner of the car has passed away, and his wife sold the car to me. She told me that her husband didn't like the alarm, so he had disabled it, and she doesn't know how to enable it either. She advised me to check YouTube, but I couldn't find any relevant information."

 

Interesting...
The only one easy and logical (to me) way of disabling alarm would be to pull off the fuse. For my Outlander it is No. 20, 7.5A one in the fuse box under the dashboard. Check other fuses in the box under the hood.