auto electrical question
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From: Fareham, Hants
Originally Posted by Gaspode,May 15 2009, 08:29 PM
Battery seems very low.
You'll get readings higher than 12V when the car is running as the alternator output is higher to compensate for a load on the battery, such as the radio, A/C etc, and to maintain the charging of the battery itself.
The figures suggest the alternator is OK, so it will be the battery, or you have a drain. You still need to check for a drain using the method I mentioned last night, if nothing is untoward is indicated when you check the battery tomorrow.
HTH
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From: Survivalist enclave
Originally Posted by loftust,May 15 2009, 08:55 PM
The figures suggest the alternator is OK, so it will be the battery, or you have a drain. You still need to check for a drain using the method I mentioned last night, if nothing is untoward is indicated when you check the battery tomorrow.
HTH
will do
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From: Peshawar
Originally Posted by RUSS H,May 14 2009, 05:51 PM
A flat battery is 12v, half charged about 12.4v, full 12.8v.
Near 10.5v a cell is knackered.
Car running around 13.5v +
Batteries tend to die very quickly nowadays.
Take a reading fully charged (12.8v), disconect earth lead
overnight and check in the morning. Should be no drop apart
from a cold related one of no more than 0.1v
Near 10.5v a cell is knackered.
Car running around 13.5v +
Batteries tend to die very quickly nowadays.
Take a reading fully charged (12.8v), disconect earth lead
overnight and check in the morning. Should be no drop apart
from a cold related one of no more than 0.1v
12.45v is low.
Have the battery 'drop' tested (or Load tested), possibly
free at some places. Takes a minute and will pinpoint
the battery most likely.
As I said batteries die quite sharpish these days not like
they used to do when they gave some warning. Usualy
at the onset of winter though.
Russ.
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From: Survivalist enclave
just tested the battery after a night unconnected
it now reads 12.40
connected the trickle charger and it went to fully charged within seconds
(btw this is the correct battery for the car and a heavy duty version)
it now reads 12.40
connected the trickle charger and it went to fully charged within seconds
(btw this is the correct battery for the car and a heavy duty version)
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From: Survivalist enclave
Originally Posted by loftust,May 14 2009, 06:03 PM
You may have a drain on your battery if the battery itself and alternator are ok, caused by an alarm, immobiliser or something similar.
To check for this, proceed as follows:
Ensure the car is off.
Set the multimeter to 'A'. If you have different ranges for 'A', use a low one, around 2 should be sufficient.
Disconnect the +ve terminal on the battery.
Connect one multimeter probe to the +ve terminal, the other one to the +ve battery lead.
If you have a reading of more than 0.1 Amps, then you have something sucking the life out of your battery.
HTH
To check for this, proceed as follows:
Ensure the car is off.
Set the multimeter to 'A'. If you have different ranges for 'A', use a low one, around 2 should be sufficient.
Disconnect the +ve terminal on the battery.
Connect one multimeter probe to the +ve terminal, the other one to the +ve battery lead.
If you have a reading of more than 0.1 Amps, then you have something sucking the life out of your battery.
HTH
all leads pointing to the battery?
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From: Hertford
You could try leaving the battery off the car; if it's drained overnight again, you cannot blame the Omega!
It sounds like the battery has developed an internal short, probably as a result of a manufacturing defect.
It sounds like the battery has developed an internal short, probably as a result of a manufacturing defect.
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From: Survivalist enclave
battery returned to Halfords
internal failure apparently - exchanged no problem so another 4yr warranty
thanks for all the advice in the thread - I must use that multimeter more often
internal failure apparently - exchanged no problem so another 4yr warranty
thanks for all the advice in the thread - I must use that multimeter more often
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From: Survivalist enclave
Originally Posted by arsie,May 17 2009, 08:33 AM
Another warranty? I thought they run from original purchase date?
BTW good thread for muppets like me ...
BTW good thread for muppets like me ...
but it's a new battery - so I can't see why the warranty doesn't restart from the date of the replacement
if not, you could have a battery replaced one day from the date of the warranty expiry
have that battery fail two days later, and be refused a replacement
can't see it, but maybe someone knows better