Troubleshooting - KYMCO MXU 450i Service Manual

Troubleshooting
Problem: Spark absent or weak
Condition Remedy
1. Ignition coil defect
ive 1. Replace ignition coil
2. Spark plug defective 2. Replace plug
3. Magneto defective 3. Replace magneto
4. ECU unit defective
4. Replace
ECU
unit
5. Pick-up coil defective
5. Replace pick-up coil
Problem: Spark plug fouled with carbon
Condition Remedy
1 . Gasoline incorrect
1. Change to correct gasoline
2. Air cleaner element dirty 2. Clean element
3. Spark plug incorrect
(too cold) 3. Replace plug
4. Valve seals cracked - missing
4. Replace seals
5. Oil rings
worn - broken
5. Replace rings
Problem: Spark plug electrodes overheat or burn
Condition Remedy
1. Spark plug incorrect
(too hot)
1. Replace plug
2. Engine overheats 2. Service cooling system
3. Spark plug
loose 3. Tighten plug
Problem: Magneto does not charge
Condition Remedy
1. Lead wires/connections shorted -
loose- open 1. Repair - replace - tighten lead wires
2. Magneto coils shorted
- grounded- open 2. Replace magneto coils
3. Regulator/rectifier defective 3. Replace regulator/rectifier
Problem: Magneto charges, but charging rate is below the specification
Condition Remedy
1. Lead wires shorted - open- loose (at terminals)
1 . Repair - tighten lead wires
2. Stator coils (magneto) grounded - open
2. Replace stator coils
3. Regulator/rectifier
defective 3. Replace regulator/rectifier
4. Battery voltage low
4 . Recharging battery
5. Cell plates (battery) defective 5. Replace battery
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