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Technical question re: battery charging circuit
Hello all,
This question is going to sound really stupid without a little prior explanation:
I have a new battery to go in my Celica. Since I got it free (dry-charged) from a previous place of work, I have no choice over the type/model etc. I have used about 20 of these batteries in the past (umm, obviously not all in the one car...) It is a 'Twinpower' battery - there are 12 cells, making two separate 12V batteries in the one casing. One half is optimised for starting (high current, short duration), the other half has different plate design optimised for low current over a long timeframe. A computer (in the battery top) switches between the two halves. It also handles the charging of the battery.
The battery has two positive terminals: a standard terminal for the starter cable, and a small terminal for the accessories wires (on most cars, these are one or more smaller wires attached to the positive terminal).
The battery NEEDS the charging current to arrive on the small, accessories terminal! I know this through a dreadful experience once where half of the battery went completely flat - the car would start, but then the battery would switch, and the car's electrical system would die. Even after I overcame this problem (by running a wire straight from the alternator to the battery) it was too late: the battery was ruined through being flat.
On some cars, the alternator is connected to the positive cable at the starter motor. This does not work for these twin-batteries, since the battery does not 'expect' to receive a charge from the starter terminal.
Now that you know the background, here's the question:
Q: Does the Celica's charging current from the alternator run through the small wire on the battery terminal, or the large wire on the battery terminal?
Thanks for your help!
-Alex
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