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Old 3rd January 2019, 18:45   #1
ballymenaman
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Default Battery banjaxed?

My V6 has been sitting unused for about a month. When I went to open it tonight the battery was so discharged that I had to use the key to open the door. I attached a 'smart' charger to the battery and it was registering at 4.7 v. I then noticed a regular clicking noise from the fusebox - probably a relay. Any ideas what's causing this? Is it safe to attach a 'fast' charger? I hate to admit it but I suspect the battery is toast!!
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Old 3rd January 2019, 18:57   #2
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Disconnect the battery and charge it for 24 hrs and you'll probably find the clicking noise has vanished (low voltage).

Depending on the age of the battery you should be able to get life back in it. I recently bought a spares or repair which had stood 3 years with a flat battery, charged / discharged a few times, now back in service.

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Old 4th January 2019, 21:02   #3
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How's your V6. Did you get it running after the battery charge ???
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Old 4th January 2019, 21:57   #4
BigRuss
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If the battery was completely flat then a "smart" charger often will not charge it, it will think it's 6v and charge it to that

To charge a completely flat battery you need a normal battery charger and put it on for a couple of hours then swap over to the "smart" charger

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Old 4th January 2019, 23:33   #5
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Banjaxed, like it.
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Old 6th January 2019, 18:30   #6
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Quote:
Originally Posted by Devilish View Post
Banjaxed, like it.
But very descriptive and can be applied to many poor old batteries.--
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Old 6th January 2019, 20:03   #7
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Quote:
Originally Posted by ballymenaman View Post
My V6 has been sitting unused for about a month. When I went to open it tonight the battery was so discharged that I had to use the key to open the door. I attached a 'smart' charger to the battery and it was registering at 4.7 v. I then noticed a regular clicking noise from the fusebox - probably a relay. Any ideas what's causing this? Is it safe to attach a 'fast' charger? I hate to admit it but I suspect the battery is toast!!
I would be surprised for a battery to be that flat after standing for just a month unless there is something draining it down?

If the battery is that flat then you will need a proper battery charger and it may well take a couple of days to fully charge, unfortunately most modern batteries are sealed so you can't take specific gravity readings - these are the most accurate way of checking the status of charge of a lead-acid battery.

I would not use a 'fast' charger, if the battery is very low with a low internal resistance the high current from a boost charger may well damage the battery.
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Old 6th January 2019, 20:52   #8
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Quote:
Originally Posted by kelvo View Post
I would be surprised for a battery to be that flat after standing for just a month unless there is something draining it down?

If the battery is that flat then you will need a proper battery charger and it may well take a couple of days to fully charge, unfortunately most modern batteries are sealed so you can't take specific gravity readings - these are the most accurate way of checking the status of charge of a lead-acid battery.

I would not use a 'fast' charger, if the battery is very low with a low internal resistance the high current from a boost charger may well damage the battery.
Don't be surprised. Nothing was said about the state of charge of the battery before being left. It might have been on its last legs then.

You can't Assume it was fully charged or anything really.----
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Old 7th January 2019, 23:07   #9
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Quote:
Originally Posted by COLVERT View Post
But very descriptive and can be applied to many poor old batteries.--

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