Starting/Charging
GENERATOR
SC-3
2. Generator
The generator has a built-in regulator which provides diagnostic functions in addition to a voltage
regulating function as follows:
1) Voltage regulation
The on-off operation of transistor Tr
1
connects and disconnects the field current circuit, providing
a constant level of output voltage.
2) Diagnosis warning
When any of the following problems occur, the charge lamp illuminates.
a. No voltage generation
Brush wear exceeds specified wear limits, field coil circuit is broken, etc.
b. Excessive output
Output voltage is greater than 16 volts (approx.)
c. Terminal B disconnection
Harness is disconnected from alternator terminal B.
d. Terminal S disconnection
Harness is disconnected from alternator terminal S. In this case, voltage is slightly greater than
specified regulated voltage; however, voltage regulation is still controlled and the battery is pre-
vented from becoming overcharged.
Diagnostic
and warning
circuit
: Alternator terminal
: Regulator terminal
Constant
voltage
circuit
Energizing
circuit
Tr3
IG switch
Charge
light
Tr1
Tr2
L
S
B
B
T
F
E
L
S
IC regulator
Minus diode (3 pcs.)
Field coil
Stator coil
Additional diode (2 pcs.)
Plus diode (3 pcs.)
Trio diode (3 pcs.)
B2H3981A
To Next Page
