20 Troubleshooting - KTM 450 SX-F 2019 Owner's Manual

20 TROUBLESHOOTING

Faults
The engine does not turn when
the starter button is pressed
Engine turns but does not start
Engine does not speed up
Engine has too little power
Engine dies during the trip
Engine overheats
134
Possible cause
Operating error
12 V battery discharged
Main fuse blown
Starter relay defective
Starter motor defective
The plug-in connection of the
fuel hose connection is not
connected
Fuel screen in the fuel hose
connection is clogged
Idle speed is not set correctly
Spark plug oily or wet
Electrode distance (plug gap)
of spark plug too wide
Short circuit cable in wiring
harness frayed, kill switch
defective
Error in the electronic fuel
injection
Error in the electronic fuel
injection
Air filter is very dirty
Fuel filter is very dirty
Error in the electronic fuel
injection
Exhaust system leaky,
deformed or too little glass
fiber yarn filling in main
silencer
Valve clearance too little
Lack of fuel
Too little coolant in cooling sys-
tem
Too little air stream
Radiator fins very dirty
Foam formation in cooling sys-
tem
Bent radiator hose
Action
–
Carry out the start procedure.
( p. 29)
–
Charge the 12 V battery.
–
Check the charging voltage.
–
Check the open-circuit current.
–
Check the stator winding of the alter-
nator.
–
Change the main fuse. (
–
Check the starter relay.
–
Check the starter motor.
–
Connect the plug-in connection of the
fuel line.
–
Change the fuel screen.
–
Adjust the idle speed.
–
Clean and dry the spark plug, or
change it if necessary.
–
Adjust the plug gap.
Guideline
Spark plug electrode gap
0.8 mm (0.031 in)
–
Check the wiring harness. (visual
check)
–
Check the electrical system.
–
Read out the fault memory using the
KTM diagnostics tool.
–
Read out the fault memory using the
KTM diagnostics tool.
–
Clean the air filter and air filter box.
( p. 72)
–
Change the fuel filter.
–
Read out the fault memory using the
KTM diagnostics tool.
–
Check exhaust system for damage.
–
Change the glass fiber yarn filling of
the main silencer. (
–
Adjust the valve clearance.
–
Refuel. ( p. 34)
–
Check the cooling system for leakage.
–
Check the coolant level. (
–
Switch off the engine when standing.
–
Clean radiator fins.
–
Drain the coolant. ( p. 114)
–
Refill with coolant. (
–
Change the radiator hose.
( p. 110)
p. 111)
( p. 124)
( p. 121)
p. 75)
p. 114)
p. 115)