donpb

After changing my battery and then getting a bunch of bogus notifications, my indy mechanic informs me that I needed to keep power while changing the battery. I'm like uh well how do you do that? He said he uses some gadget connected to the obd2 port.

I found out its called a memory saver and there's tons of different types.

My question is, isn't there other ways to do this like connecting a battery charger to the front battery terminals? Also, I see the ones that connect to the lighter port but how in the heck would that work when the lighter port is off? Yeah I long since noticed my lighter port shuts off after a bit. Is anyone else using a memory saver or what technique do you use? Thanks.

kd7iwp

You're correct that the lighter turns off with the ignition so that would not work. I've never bothered to keep anything like this running. I don't see why your idea of putting a charger on the front terminals wouldn't work. I personally wouldn't use the OBD2 port because I don't think it would be able to handle much current and if the fuel pump tried to prime, or lights turned on, etc. while you disconnected the battery it might try to pull too much current through there. I also personally wouldn't bother as the only thing that seems to happen to me when I disconnect the battery is I have to set the time, and occasionally I need to turn the steering wheel lock to lock to reinitialize the steering angle sensor.

FormerE30Owner

I just connect a booster battery to the front terminals. I don't think that a battery charger would suffice.

donpb

That sounds like a good idea.

donpb

Normally nothing happens but this time a lot of notifications sprang up that I cannot clear and so I have to pay my mechanic to clear them. That's when he told me I needed to keep power to the car when disconnecting the battery.

cmyachtie

sounds like BS to me as I have one of those memory savers and never used it as despite having had battery disconnected for days several times never had an issue with either radio nor seat memory being lost.

Just get an AFS AND DSC code upon startup and after initializing the steering, All is well again....

donpb

I stated that nothing usually happens like you say but not this time.

rice_rocket88

I have done it before with a battery tender attached... however, I have had the instance where changing it and a battery tender was not available, still no problems. It is possible that you could have new codes thrown after it, but once you clear it you're good to go. I'm not sure why/how there is/was residual electronics, but the test was looking at the clock, after swapping the battery without any aux power the time stayed consistent so.. there you go.