Toyota 3S-GE Repair Manual page 469

CHARGING SYSTEM — OPERATION CH-5
SW20
MAIN §
L 2.0L
F IC Regulator
P18023 213242
Ignition Switch
U O
. ALT
AM2 ECU-IG sencing
S7.5A . 7.5A S75/\
L IG S +B
O
§Ai.T §AM2 1
120A 40A ' L |G 5 +5
o——r——-0—--
Battery lg
I
O E
_ = Alternator I .1.
5
Ignition ° ° °
Main ' . . _ Charge
2 3 Warning WW
RelaV "1 S Light er
. . a , I
4 '
OPERATION
CHO0P—OF
When the ignition switch is turned ON, current from the battery flows from terminal L of the
alternator through the IC regulator to terminal E, causing the charge warning light to light up.
When the engine is started, the voltage output increases as the alternator speed increases. When
the voltage output becomes greater than the battery voltage, current for recharging flows from
terminal B. Simultaneously, voltage at terminal L increases and the potential difference between
battery and terminal L disappears, causing the charge warning light to go off. When the voltage
output exceeds the regulator adjustment voltage, the transistor inside the IC regulator regulates
the voltage so that the voltage from the alternator remains constant.