På lite äldre Volvo kunde man få problem med klimat anordning samt lite annat smått om batteriet togs ut för snabbt.
Skadar inte att följa denna instruktion.
The following sequence is what Volvo specifies whenever you dis/reconnect battery
Wait 5+ min after key is out to make sure everything in the car is off. I turn everything on the ECC is off for safe measures (AC, fan..)
Disconnect negative terminal
When you are ready to reconnect the battery, do this.
Insert key and switch to position II
Reconnect negative terminal
Turn the key to off
Lock and unlock door (reset upper cabin electronics, without this step, your sunroof/homelink may not work)
Now set your clock
Källa
http://howardsvolvos.webs.com/miscissues.htm