How to maintain computer memory when changing batteries?

Hendoo · Post by **Hendoo** » 18 Mar 2018, 23:41

My car is a 1999 S80 2.9.

I need to install a new battery in my S80. The owners manual says to turn off and remove key, wait 10 minutes, then change the battery. Battery is in the trunk, with easy access.

So I presume there are no radio codes to contend with. BUT -- I expect I will lose all the radio presets, homelink settings, etc if I do this.

I have a Battery Minder... can I just hook it up to the + terminal in the engine compartment and ground and change out the battery? This is a "smart charger". I also have an old dumbo 12V charger.

Or am I better off buying a "memory saver" that applies power through the OBDII port?

I don't mean to over-think this... but this car seems to be very sensitive to voltage levels so I don't want to cream anything.

Thanks!

-Hendoo

Waynefife · Post by **Waynefife** » 01 Apr 2018, 09:45

Take a hand held 9 volt battery and some wire with clips and attach it at fuse box

Post by **RickHaleParker** » 01 Apr 2018, 13:41

I have a Battery Minder... can I just hook it up to the + terminal in the engine compartment and ground and change out the battery? This is a "smart charger". I also have an old dumbo 12V charger.

Might work but those are unfiltered. The battery acts as a filter.
Another battery and some jumper cables would be a better idea.

Post by **kranz** » 01 Apr 2018, 14:49

I've disconnected & reconnected the battery on my P2 & P80 and it has no effect on the Homelink.

Post by **jimmy57** » 01 Apr 2018, 20:32

If the battery is not disconnected for more than a minute during the swap then there is almost no loss of anything. The capacitors in the modules will support memory retention for that long.

Post by **gstallons** » 15 Dec 2019, 08:55

Get the Memory Saver and uce it . This will keep everything in memory while you exchange the batteries .