You really need a garage to do a proper test on it to assess its condition.
Also no way is it fully charged after 4 minutes! If it's a normal amateur battery charger it needs an overnight charge to fully charge up a dead battery, try that and see what happens.
If the battery's more than 5 years old it's done well and may just be worn out, they don't last forever.
You sure you know how to use a multimeter?
The jacks in the meter are for running an amp test in series,usually with the consumer in circuit,and internal shunt in the meter means there's a fraction of the current actually running through the meter circuits,
just as well as it could be fried!
If you read the label on the battery there will be a section marked CCA,or cold current amperes,
average medium petrol car battery is around 650-750 amps,enough to weld let alone cook the meter.
As Frank stated the battery needs load tested,
a drop load tester has a huge current carrier wire,or a carbon pile.
Mine you dial in the CCA and press test,
and the tester get's HOT!!
My procedure is put it on charge for 24 hours,12 hours alter drop test it,
Few pass this test with anything better than 50-60%
A normal car battery will have between 150 and 700 amps available, depending on the type and size of engine and starter. If you're using a small multimeter they only read up to about 10 amps (should say on the meter), you would have to use an inductive amperage meter or a battery load tester to get an accurate reading.
If you put a meter across the battery terminals with it set to amps you are effectively short circuiting the battery. In fact, some part of your meter internals are probably fried. A battery with 12.81 volts showing under no-load conditions is probably past its best - put it back in the car, turn on all the lights and then see what the voltage is.
Hi, I parked my car up the other night (I just bought it) and all was fine.This morning I went to start it but it struggled to turn the starter motor. So i put the battery on charge but after 4 minutes the charger said it was fully charged. So now I have the battery on a bench. The voltage off my tester says 12.81v, but when I test the current (A) there is no reading, not even in micro amps (and yes i know how to use the tester and change ports for Voltage and ampage ect). What i want to know is, what should the ampage of a regular charged (12.8v) car battery be sitting on the bench.
Im not sure if the battery just has no current left in it, or if my tester is broken. When i ark the terminals there is a semi healthy spark so there is some current in it, its just not showing on my meter. I hope the battery is faulty and not the starter motor. Any mechanics out there offer some advice please.
