Why does the i2c scanner not see the DS1307 clock module?

Question

Arduino

I bought a ready-made real-time clock module DS1307 on Ali. I connected it to arduino nano and uploaded a sketch to set the time (iarduino RTC). The download was successful, but the port monitor shows 00-00-2000, 00:00:00, Dec.
I also tried to scan with an i2c scanner, but it does not see anything.

What could be the problem?

Answer 1

- Connected incorrectly
- Connected to the right place, but bad contact
- Faulty module
...

Answer 2

I didn't quite understand the problem. But is it not so that the time must first be initialized, before being read later?

Answer 3

What exactly is the DS1307 module? Are pull-up resistors installed? Is the "CH" bit in the seconds register correct?