um CHILL 125 cc. Service Manual page 39

Diagnostic Help：
 Make sure there is no any issue record of the engine.
 Make sure the issue could repeat.
 Have checked follow the instructions above and no cause found.
 Do not ignore the maintenance situation, cylinder pressure, mechanical timing and fuel quality.
 Change the ECU and repeat the test, if the issue is gone, then the root cause is the ECU. Or change the old one back to check the root cause.
Engine cannot start
ITEM OPERATION
1 Check whether the voltage of the battery is around 8-12V.
2 Crank the engine, and check whether the voltage is above 8V.
3 Check whether the start motor working well or not.
CHILL 125 cc. SERVICE MANUAL AND EFI DIAGNOSTIC
RESULT
Yes
No
Yes
No
Yes
No
NEXT STEP
Next
Change the battery.
Next
Change the battery.
Next
Change the start motor.
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