Volkswagen Beetle (1998 - ) - do I need to disconnect battery whilst charging ?

Honest John Back Room » Technical matters
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Fri 30 Jan 2009 06:57
do I need to disconnect battery whilst charging ? - DavidGlos
Morning All,

With a view to keeping the (fairly old) battery on my car in a decent state of charge over the winter, I purchased a small battery charger last night.

Had a look through the instructions and all the usual blurb about checking water levels and topping up with distilled water was there, together with the need to remove the top/caps on the battetry to allow gases to escape whilst charging.

The instructions then went on to strongly recommend that the battery was removed from the car prior to charging. If this is not possible, it stated that the battery should be disconnected from the car whilst charging, to avoid possible alternator damage.

What are the Backroomers thoughts on the need for this? Can't say I've ever disconnected the battery from the car before? Presumably this would result in the ECU resetting itself, needing to dig out the code for the radio etc. Is it really necessary to disconnect the battery from the car, or is this just the manufacturer trying to cover their backs?

It's only a 4 amp charger and would be left on overnight.

Edited by Pugugly on 30/01/2009 at 09:53

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Fri 30 Jan 2009 07:26
Battery charging - disconnect battery from car? - grumpyscot
I've charged batteries many times and never disconnected them. But I do always drape a scarf or tie or cloth over the steering wheel so that I remember when I jump into the car and before I fire up and cause damage to anything.

I know autoelectricians often plug in things that look like cigarrette lighters with a PP3 lattery attached so that the radio can keep its settings. But often the car alarm will still go off when you disconnect the battery - my Saabs certainly did!
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Fri 30 Jan 2009 08:03
Battery charging - disconnect battery from car? - Pugugly
Optimiser type chargers charge in situ.
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Fri 30 Jan 2009 09:13
Battery charging - disconnect battery from car? - JH
David
any chance you might be able to return and get something like - tinyurl.com/dgq6kj ?

JH
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