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battery polarity question

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nevets

nevets

Jedi Knight
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I inadvertently hooked up my charger to my BN6 battery with the polarity (of the charger cables) reversed and discovered it after several hours of charging. As you might imagine, the battery did not get charged and since it was old, I have since replaced it with a new one….Pos terminal to ground, neg to the starter cable. Everything appears fine now, but I am wondering whether there was any risk of damage to the car's electrical system, and on a related note, just what are the consequences of reversing the battery polarity? Thanks in advance to Keoke and others who wish to share their wisdom.
 
HI nevets, I do not think the car suffered any Ill affects, but there should have been sparks at the terminals when you tried to hook up the charger. This is usually a warning sign. A method that may help keep ones polarity straight is to purchase color coded battery terminals and install them on the cable ends, or paint those on the car.---Fwiw---Keoke
 
I didn't see sparks...I think because I didn't plug in the charger until after the clips were hooked up to the battery. Plus the battery was fairly dead at the time. Thanks
 
As long as you didn't turn anything in the car on while the battery/charger were reversed, there shouldn't be any damage. If you did, there is some possibility of damage.
D
 
No Dave, nothing was turned on, and as I said, all seems well now with the new battery installed. It did give me a scare though...being fully aware of the unpredictable nature of Lucas electricals (touch wood).
 
As a matter of trivia, it is possible ,with a completely discharged battery, to connect the charger reversed & charge the battery up in the "reversed" polarity. You now have a battery with negative on the positive marked terminal & vs. This can cause complete confusion & parts damage. It HAS happened a few times.

This condition can be partially corrected by completely discharging the battery & recharging it in the correct direction. Battery life will be considerably shorter after this has been done.
 
Have reversed polarity on mine so as to fit alarm and inertia switch etc, now all I have to do is put some decals on to alert anyone working on it that it is neg ground now
 
Zblu, go to a land Rover dealer they have some nice red ones printed up on aluminum that work great.I have them positioned in the boot of my car just above the battery,or you could also glue it to the top of the Control Box.---Fwiw---Keoke
 
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