Ignition System Troubleshooting - Honda CB250N Shop Manual

Ignition
System
Troubleshooting
•
inspect the fallowings before diagnosing the system.
—
Faulty
spark
plug.
—
Loose spark
plug
cap
or
spark plug wire connections
—
Water
got into the spark plug
cap (Leaking the
ignition
coil
secondary
voltage).
*
Temporarily
exchange
the ignition coil
with the other
good one and
perform the spark
test.
If
there
is
spark, the
exchanged
ignition coil
is
faulty.
IMo spark
at all
plugs
Unusual condition Probable
cause (Check
in
numerical
order]
Ignition
coil
primary
voltage
Low
peak
voltage.
©
The
multitester
impedance
is
too low.
©
Cranking
speed
is
too low.
•
Battery
is
undercharged.
@
The
sampling timing of the tester
and measured
pulse
were
not synchronized.
(System
is
normal
if
measured
voltage
is
over the standard voltage
at least
once).
©
Poorly
connected connectors
or
an
open
circuit
in ig-
nition
system.
©
Faulty exciter
coil.
(Measure
the
peak
voltage.)
@
Faulty side
stand switch
circuit.
©
Faulty
CDt
unit (in
case
when
above
No.
©—©
are
normal).
No
peak voltage.
©
Incorrect
peak voltage adaptor connections.
©
Short
circuit in
engine stop switch
wire.
©
Faulty
ignition
switch or
engine stop switch
@
Loose
or
poorly
connected CDI
unit connector.
©
Open
circuit or
poor connection
in
ground wire
of
the
CD!
unit.
...
©
Faulty side
stand switch
circuit.
©
Faulty
peak
voltage adaptor.
®
Faulty exciter
coil.
(Measure
the
peak
voltage.)
©
Faulty pulse generator.
(Measure
the peak voltage.)
©
Faulty
CDI
unit
(in
case
when above
No.
©
—
©
are
normal).
Peak
voltage
is
normal,
but no spark jumps
3t plug.
©
Faulty spark plug
or leaking
ignition
coil
secondary
.
current.
@
Faulty ignition
coil.
Exciter
coil
Low
peak voltage.
©
The
multitester
impedance
is
too low.
©
Cranking speed
is
too low.
Battery
is
undercharged.
@
The
sampling timing of the tester
and measured
pulse
were not synchronized. (System
is
normal
if
measured
voltage
is
over the
standard ^oltage
at least
once).
©
Faulty exciter
coil (in
case
when
above No.
©—
©
are
normal).
No
peak voltage.
©
Faulty
peak voltage adaptor.
©
Faulty exciter
coil.
Pulse
generator
Low
peak
voltage.
©
The
multitester
impedance
is
too low.
@
Cranking speed
is
too
low.
•
Battery
is
undercharged.
@
The
sampling
'timing of
the tester
and measured
pulse
wore
not synchronized. (System
is
normal
if
measured
voltage
is
over the standard voltage
at least
once).
©Faulty
pulse
generator
(in
case
when
above
No.
©—
©
are normal).
No
peak
voltage.
©
Faulty peak voltage adaptor.
@
Faulty pulse generator.
14-3