If you are in your original 12V batteries (there are two), then you really need to have them replaced as they tend to fail after a couple of years and cause no end of troubles when they die. There are dozens of threads here on this.

 

It really helps if people posting fault codes identify what modules the fault codes come from. It is a lot easier to give advise rather than having to do research to determine this basic information.

U2109-09 comes from the TCU. That battery can be replaced by user but requires accessing the TCU behind the left loadspace trim. Ideally, one would have a scantool that can run the routine to reset the TCU knowledge of the backup battery replacement.

P06B8-42 comes from the Occupant Monitoring Module. The first course of action is to clear the code and see if it comes back. It could have been set by a transient condition.
Jaguar recommended action:

• Using the Jaguar Land Rover approved diagnostic equipment, clear the DTCs and retest. Turn on the vehicle and use the touch screen to create a new personalization profile. Turn the vehicle off. Turn the vehicle on and select the profile. Check for DTCs, if the fault persists, install a new occupant monitoring module.

What is wrong with the brake light?

 

I don't know if the 2 12v batteries have been changed, I ordered the battery for the TCU, while for the occupant module, I try to delete the profile and make a new one, the DTC seems to no longer delete after the first time but the brake works well

 

I don't know if the 2 12v batteries have been changed, I ordered the battery for the TCU, while for the occupant module, I try to delete the profile and make a new one, the DTC seems to no longer delete after the first time but the brake works well

 

The TCU backup battery is a 3+volt tesla/type lithium battery. You can buy it at most battery supply businesses. The TCU battery voltage can be monitored with a scan tool. I used a Scangauge with the following settings:

TCUBatt 3.75V

TCUBatt3.75V

075422d90b

046205D9060B

3008​

006400FF0000

Volts

 

Thanks