How to disconnect battery & avoid fault codes?
 

I have been reading about several fault codes caused by other seemingly routine maintenance work.
Is there a procedure for disconnecting the battery in my 2004 V70 N/A that would prevent these codes? Is there a time period I do not want to exceed or one I must allow to elapse?
What about making a 9 volt power supply to plug into the 12 volt power supply (cigarette lighter) during battery disconnect?

Thanks for the replies,
Dennis

I hear people damaging their electronic climate control (ECC) units while removing the battery. Here is what I do

Turn off everything on the ECC
Wait 10min (ECC has stuff running even after car is off)
Disconnect negative terminal

Before reconnect the negative terminal
Turn key into position II, then reconnect. All Volvo directions that calls for power interrupt spec this step to reconnect power.

Click door lock/unlock if your door lock/sunroof don't work. It resyncs upper cabin electronics.