KS Motorcycles K-LIGHT125, Maintenance Manual

Page: 274 / 278

d) Storage battery voltage—determine whether the power of storage battery is sufficient
e) Determine whether coolant temperature sensor, intake temperature sensor, intake manifold absolute
pressure sensor and oxygen sensor display value are normal
f) Working range of throttle position sensor—it cannot be fully opened or closed, which may affect engine
power performance and some system functions
18.4.2.2 Step II
Check whether ECU power is turned off—the communications between diagnostic apparatus and system is
interrupted after turning off key switch
18.4.2.3 Step III
a) Coolant temperature and coolant temperature cycle—predicts whether the thermostat is working properly
b) Storage battery voltage —Indicate whether the generator is working properly.
Too high: there may be fault in voltage regulator;
Too low: there may be improper connection of generator or generator fault
c) Intake manifold pressure—it can predict whether there is leakage in intake and valve clearance problems.
Valve clearance is too small: this value is too high, so engine power performance may be affected; in
addition, due to too early opening of exhaust valve and increase in exhaust temperature, oxygen sensor and
three-way catalytic converter service life may be significantly shortened;
Valve clearance is too large: it may cause low intake manifold pressure, and thus affect the system to
determine the working state of engine, thus resulting in abnormal idle speed during warm-up of
motorcycle.
In addition, if the exhaust system is blocked, for example: a foreign body exists in the exhaust channel; the
oil consumption is too high, thus blocking three-way catalytic converter; three-way catalytic converter is
blocked due to internal damage, which will cause slightly high value.
d) Number of cycles of oxygen sensor value—the number of cycles is too small, indicating fault of oxygen
sensor
18.4.3 Simple Troubleshooting
Please follow the following steps to repair EFI system. To repair fault in one step, the subsequent steps may
be stopped. And then use diagnostic apparatus to conduct inspection and acceptance and clear fault code
according to Section 14.4.2 “Engine Working Data Flow Displayed by Diagnostic Apparatus”.
When using diagnostic apparatus, the voltage of storage battery should not be lower than 8.5 V.
18.4.3.1 Daily Use and Maintenance

92# or 95# gasoline should be high quality without lead.

ECU has a moisture-proof function, but high-pressure water gun should not be used to rinse its shell.

The petrol filter should be changed every 7000-10000 km.

Under normal conditions of use, clean the throttle body every 10,000 km or 1 year.
18.4.3.2 Fault phenomenon-Start Fault
a) Rotate ignition switch to “On” position, and check whether engine fault lamp is on.
- 273 -
KS MOTORCYCLES - https://ksmotorcycles.com