Replacing a battery

I know this question has come up here before,but i have never seen a definite yes ,or no to just change out a battery.

Disregarding the need to save the radio memory code,can this be done without concern for other car electronics on vehicles from 2005,and on?

It depends on the make/model.


How about a 2004 GMC pkup,and a 2007 honda Accord

Read this. Especially look at what can happen to GM trucks with 4WD when the battery is disconnected.


I replaced my battery and considered it cheap insurance to buy the 12 dollar part that supplied voltage to the obd so as not to reset the memory. The guy at the auto kids store was like, you plug it into the lighter, I said if you disconnect the battery, what good will that do! Then he was RIIGHT, ok you plug it into another car. The cord was really short,maybe 3 feet at the most, but I have a 12 volt power supply I adapted for testing purposes with the power point or cig lighter adapter as you prefer for other things at work I fix and test that did the trick. I Have an 03 blazer and had read enough troubles after a battery change, though I have had 2 resets of the computer without issue.

Short story, Do you feel lucky, or do you want a guarantee of no computer reset. There are also other adapters I have heard of including a nine volt battery for the cig lighter or power point to avoid problems.

It is almost like not stepping on a crack to break your mother’s back, who knows, I don’t.

Edited, 3 responses in the time it took me to type my response, man I thought this was ignored, and now I am late news.

I went and looked for any TSB about the battery disconnected inoperative status of the “4wd module” as described in the article Tester related and there is none. This article should for the sake of its own credibility state what trouble code is displayed by this module when it is in this inoperative state. Even a module that you can’t talk to will have a code saying in effect “I can’t talk to you”.

I do not know why Tester’s link did not work for you. I have read enough reports it was important to me, and tester.

I guess I’m off to get,or make one of those battery memory retainers.
Kind of upsetting car manufactures don’t have a warning in their owner manuals.

Neither my GMC,or Honda have one.

You can get a MEMOR-EZE from any auto parts store for about this price.

Just make sure the lighter/power port is hot with the key off. Otherwise it doesn’t work.


If you need here is the alternate from autozone I used that worked just fine.

Our Nearest Wal-Mart Sells The “Noco Settings Keeper” For $4.97, Including 9v Battery.


Waterboy, What Did You Plug Into For Power ?? One End Is OBD2 And The Other Lighter Socket That Will Be Powered Down.


Tester, The Noco Settings Keeper Has Instructions For Cars With Lighter/Power Ports That Are Not Hot With The Key Off.

Some vehicles may require ignition to be in the accessory position.

They also warn, “Make sure All possible sources of power drain (ex. dome, dash, car door, compartment, hood and trunk lights, as well as fans, radios, A/C-heater blowers, mobil phones, etc.) are shut off or temporily disabled (ex. remove fuses and /or bulbs while using this product.

Does this sound feasible on cars without an ignition-off hot socket ?


I can explain why the link did not work.I will be repeating myself to some extent. The link did not provide specific codes generated by the inopertive “4wd module” in the Tahoe (and a code should have been generated and the article should have stated what code was generated). In addition the link used generalized terms, it was not technicaly specific enough and made alot of hay about engines and transmissions relearning adapative settings, they are designed to do this re-learning.

On my 1999 Camry the lighter is not hot even in the accessory position it has to be in the run position. I would think that would create too much draw for a 9 volt battery. I guess you’d might be ok if you pulled every fuse but the one to the lighter and ECU, but how many people will do that, given the multiple fuse boxes and ones hidden under rear seats etc. Or I guess you could just do it the old fashion way and clip a 9v right to the battery cables.

At work I made an adapter from an old large 12 volt power supply. I clipped the wires that went to laptop or whatever it was from, put on a couple of female spade clips and connected those to a replacement socket available at any parts store. It is very handy not to have to run out to a vehicle if things need testing. If you make one just be sure the positive 12v dc goes to the center of the socket. I imagine you could get an extension and plug it into another car also.

I found two types of battery savers. Both have a cigarrette lighter plug on one end,BUT the other ends have either a OBD II connector,or the 9V battery connector.
Whats the difference.
I have two different vehicles,a truck and car,that i would use it on to replace a battery.
Whatcha think?

Recap, ie the short story. If your cars powerpoint (cig lighter) is active with the engine off the 9volt battery to the cig lighter will work, but remember every time you open the car door the interior lights may go on so there is a potential to drain the 9v battery and negate the protection.

The one that plugs into the odb needs a power source independent of the car in which you are changing the battery. How you supply that power is your choice. If you get an extension cord you may be able to plug it into another car, power supply if you have one or even a battery maintainer connected appropriately.

Stuff that works is what I think.

You can connect a 9V battery to the battery cables at the battery, using clips or small clamps, + to + and - to - . When you disconnect the battery cables, the 9V battery remains in place and supplies enough juice to keep memories intact. No need to involve the ignition key or the lighter/power outlet circuit. But turn off unnecessary battery loads like cell phone, and keep the doors closed so interior lights don’t come on.

Thanks to all who responded to my query.