jpv7774

This has become an issue with newer cars. Recently I helped my brother in law by changing his battery for him on a Chevy Avalanche truck. After the battery change the trucks computer lost its memory and the truck ran like crap. Now since I have done a lot of DIY on my LS430 I have had to disconnect my battery a couple of times and my understanding is that this would cause a soft reset. Well recently I paid the dealer $300 bucks for the transmission shift software upgrade and the car has been shifting perfect ever since. Now I have heard rumors that if I disconnect the battery now that I will lose my software upgrade.......I do not know if this is true or not...I wish I did. So I am thinking until I talk to Lexus and get a definite answer.....I would like to use a memory saver. I just watched several You tube videos about this and it seems like the smart way to go.

Who is using this type of device? Which one are u using? Any tips or tricks? Anyone know for sure if I would use my software upgrade?

Thanks

isfdude

iTrader: (11)

When it comes to software disconnecting the battery will not erase what was programmed. Most cars will take some time to learn quick test on the engine and the Windows might need to be relearned meaning every window switch will have to be used to roll down the window and roll it back up one at a time. Battery's die all the time and for no reason. I highly doubt that replacing the battery will erase any info that was programmed in to the computer. But if you want too just keep it attached to a booster pack or run jumper cables to another car and make sure you done bump off the cables while changing the battery.

jpv7774

isfdude.......I kinda feel the same way. My next question then would be if I hook my jump pack to the battery what is making sure the car isnt getting too much juice. Essentially that is 2 12volt batts hooked up at the same time. I understand this occurs w jump packs all the time and I also understand a jump pack usually isnt packing the same power as a charged new battery unless it is brand new. I guess since not wired in series it just comes through as 12 volts? Because sometimes I am disconnectin a very new very hot battery just to do repairs.......so a hot battery and a charged jump pack would pack a wallop wouldnt it?

Brewmyown

I use a a device that plugs into the OBDII plug whenever I swap out a battery. It's a rechargeable device that will hold all the memory for quite a while.

jpv7774

Ya Brew......I saw some of those on Youtube. They are pretty slick. Which model do you use? What is the sequence of using the device?

Where did u purchase?

Brewmyown

This is what I use. It's rechargeable and holds the memory a long time.

jpv7774

yes sir....that thing is the ticket! So u charge it via a plug in charger......it holds enough charge for say a month between charges to do some DIY jobs....then u charge again. Does that connector plug into any cars OBD thing? I have never used the computer port before.

Brewmyown

All you do is plug it into the OBDII plug and turn it on. There's nothing to it. They are only $50 - $60 now online. The one I have is a few years old and I think it was under $50 at the time.

jpv7774

perfect...thanks....I will pick one up.

Brewmyown

The plug is standard in all cars so yes as long as it's a post 1996 car it will work. As far as holding a charge, I've gone several weeks without recharging it and it worked fine for a battery swap, etc. Theres a light on it that lets you know it's charged. Flick the switch. If the light goes on it's good to go. If not, plug in the charger and use it right away.

jpv7774

cool...thanks

Brewmyown

While you're at it grab a cheap ODBII scanner for $25 on Amazon. It won't do everything but it will give you generic codes for most engine or emission system issues. Also erases codes in case there a false positive. Just erase it and see if it returns.

My two daughters both drive 1999 Honda CRV'S and are away at college. I have one in each of their cars. If one of the cars throw a code, they hook it up and read me the code. 9 out of 10 times it's an emission fault that doesn't affect the driving and then I know it's safe for them do drive until the next time they are in town.

Brewmyown

Here's the one I bought for both of them

isfdude

iTrader: (11)

Unless you cross the positive and negative on the battery it will be fine. It will only add more amps to the system not 24 volts. The voltage will be safe.

Brewmyown

Yes, what he said.