disconnecting the battery on a vehicle

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=99416
Printed Date: April 26, 2024 at 7:33 AM

Topic: disconnecting the battery on a vehicle

Posted By: rosedalechip
Subject: disconnecting the battery on a vehicle
Date Posted: November 27, 2007 at 10:53 PM

I have heard that on some cars removing either the negative or positive post on a car battery first would keep the vehicles computer settings from getting screwed up. Is there a right way or a wrong way to remove a battery? Is this true on certain cars? Can anyone verify this? Excuse me if the questions seem silly ! I just don't like not knowing.

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I hear voices in my head !

Replies:

Posted By: haemphyst
Date Posted: November 28, 2007 at 12:32 AM

My understanding is that neither will or should matter. Once you disconnect the power from EITHER terminal, the car is electrically dead.

I can't see how disconnecting one or the other first could make any kind of a difference.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Posted By: rosedalechip
Date Posted: November 28, 2007 at 11:39 AM

Thanks I appreciate it.

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I hear voices in my head !

Posted By: donpisto
Date Posted: November 28, 2007 at 12:29 PM

Disconnect: negative then positive

Reconnect: positive then negative

If you were to disconnect the positive first, your vehicle is still grounded, that's a no-no. Also, if you're wanting to hook up an amplifier and whatnot, just disconnect the negative and that's it.

Posted By: audioman2007
Date Posted: November 28, 2007 at 2:42 PM

i have a 02 cavalier and I am able to disconnect both battery terminals without losing my computer info. I just need to reconnect in a certain amount of time

Posted By: haemphyst
Date Posted: December 11, 2007 at 1:34 PM

donpisto wrote:

Disconnect: negative then positive
Reconnect: positive then negative

There is a perfectly valid reason for that. If you disconnect the positive first, the car is still grounded to the battery, and the possibility of landing a tool across the positive terminal and the chassis is very real. In a positive ground car, such as older VW bugs, you disconnect the positive terminal first, for the same reason.

donpisto wrote:

If you were to disconnect the positive first, your vehicle is still grounded, that's a no-no.

There is no other reason than what I have stated above to remove the negative battery cable first. It's for safety only.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Posted By: advanced_audio
Date Posted: December 11, 2007 at 1:39 PM

Also would like to add, make sure you have the code for the radio if it has the theftlock crap on it, before you disconnect the car from the battery.