2003 SL500 R230 error codes

[Hung Hua]

Error codes from 2003 SL500 59K miles. The car is running fine. The AC is working good and providing cold air (39 psi low, 220 psi high, ambient temp 66 F, center vent temp 43 F). I like to fix the error, but can live with them if they are too costly or too hard to fix.

LCP B1010 Control unit faulty. Power supply low
The original 6.5 years old battery will be replaced soon. Should take care of this error code.

AIRCO B1269 CAN communication error with the KLA multifunction sensor.
What does this mean? What are CAN and KLA?

AIRBAG B1315 Child seat recognition. wiring error communication error short circuit to PLUS.
Any idea what to look for? What is PLUS?

PSE B1436 Central locking secure time too long, air capacity too high.
Any idea where to start?

TIA for any help.

Regards