Checking The Ignition Coil; Ignition System Troubleshooting - KTM 250 SX-F 2005 Repair Manual

Ignition system troubleshooting

Check the emergency OFF switch before you test the ignition system.
Check whether there is an ignition spark upon starting, proceeding as follows:
– Pull off the spark plug connector.
– Disconnect the spark plug connector from the ignition wire
– Hold the loose end of the ignition wire approx. 5 mm from the ground.
– A strong spark should be visible when the kickstarter is actuated.
– If a spark is visible, mount the spark plug connector again.
– Unscrew the spark plug and insert in the spark plug connector.
– Hold the spark plug against the ground. A strong spark should be visible when the kickstarter is actuated. If not, the spark
plug connector or spark plug is defective.
If no spark is visible during the first test, check the following parts:
– Emergency OFF switch
– Cable tree parts belonging to the emergency OFF switch.
– Test with a peak voltage adapter
If the ignition is being supplied with voltage but no spark is visible, check:
– The ground connection from the CDI unit and ignition coil
– The cable from the CDI unit to the ignition coil
– The pulse generator
– The stator
– The ignition coil
– The short-circuit button
NOTE: the CDI unit cannot be tested with simple devices. It can only be tested on an ignition test bench.
CDI unit
Check the cables and socket connections to the CDI unit.
The CDI unit can only be tested on an ignition test bench.
!
N CDI
EVER TEST THE UNIT WITH A CONVENTIONAL MEASURING DEVICE
SENSITIVE ELECTRONIC COMPONENTS COULD BE DESTROYED

Checking the ignition coil

– Disconnect the ignition coil and remove the spark plug connector.
– Use an ohmmeter to take the following measurements:
NOTE: the following measurements only correspond to the setpoint
values at a coil temperature of 20° C.
Replace the ignition coil if the measured values deviate significantly
from the setpoint value.
Measurement Cable colors
Primary coil blue/white - ground
Secondary coil blue/white - ignition wire 6.30 kΩ ± 1.25 kΩ
CAUTION !
.
Resistance
0.30 Ω ± 0.05 Ω
7-2
. H
IGHLY