Jianshe JS125-6B Maintenance Manual page 190

3. Charging voltage
Connect inductive tachometer to spark plug lead.
Connect the pocket tester(DC20V) to the battery
Tester lead Battery+terminal
Tester lead Battery-terminal
Start the engine and accelerate to about 5000r/min
Check charging voltage
Charging voltage: 14.0V 5000r/min
Note
Use a fully charged battery.
4. Ignition, charging coil resistance of battery
Disconnect charging coil coupler form the wire
harness.Connect the pocket tester(
charging coil.Measure the charging coil resistance.
Tester lead White terminal
Tester lead Green terminal
Charging coil resistance
0.4
5.Wiring connection
Check the connections of the entire charging system.
Refer to Circuit Diagram .
Re-install the rectifier regulator
Out of specification
1) to the
20%(20 )
Meets specification
Correct
CABLE AND ELECTRIC APPLIANCE SYSTEM
The charging circuit is correct
Charging coil troubleshooting, replace it
180
Meets specification
Out of specification
Poor connection
Repair it.