IGNITION SYSTEM
• Inspect the following before diagnosing the system.
- Turn the ignition switch ON and engine stop switch
"0",
check the OTC (page
4-15).
MIL
52
blinks (CKP sensor)
is
indicated only when the engine
is
cranked.
- Faulty spark plug
- Loose spark plug cap or spark plug wire connection
- Water
in
the spark plug cap (Leaking the ignition coil secondary voltage)
• "Initial voltage" of the ignition primary coil is the battery voltage with the ignition switch turned ON. (The engine is not cranked by
the starter.)
No spark at spark plug
UNUSUAL CONDITION
PROBABLE CAUSE (Check
in
numerical order)
Ignition coil
No
initial voltage with the ignition
1.
An open circuit or loose connection
in
the Black/white wire.
primary
switch turned
ON
and engine stop
2.
Loose or poor connection of the ignition coil primary wire
voltage
switch
"O".
(Other electrical terminal or
an
open circuit
in
the primary coil.
components are normal)
3.
Faulty ECM
(in
cases when the initial voltage
is
normal when
ECM
21
P (Black) connector is disconnected).
Initial voltage
is
normal, but it drops
1.
Incorrect peak voltage adaptor connections. (System
is
by 2 -
4
V while cranking the engine.
normal if measured voltage is over the specifications with
reverse connections.)
2.
Battery
is
undercharged. (Voltage drops largely when the
engine
is
started.)
3.
Loose or poor connection or
an
open circuit
in
the Yellow/blue
wire between the ignition coil and ECM.
4.
A short circuit
in
the ignition primary coil.
5.
Faulty CKP sensor (Check the OTC: page
4-15)
6.
Faulty ECM (in cases where No.
1
through
5
are normal).
Initial voltage is normal but there is
1.
Incorrect peak voltage adaptor connections. (System is
no
peak voltage while cranking the
normal if measured voltage
is
over the specifications with
engine. reverse connections.)
2.
Faulty peak voltage adaptor.
3.
Faulty ECM
(in
cases where above No.
1
and 2 are normal).
Initial voltage
is
normal but peak
1.
The multimeter impedance
is
too low; below
10
MQ/OCV.
voltage is lower than the standard
2.
Cranking speed
is
too slow. (Battery
is
undercharged.)
value.
3.
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.)
4.
Faulty ECM (in cases where above No.
1
through 3 are
normal).
Initial and peak voltages are normal
1.
Faulty spark plug or leaking ignition coil secondary current.
but no spark jumps.
2.
Faulty ignition coil.
To Next Page
Loading...
Need help?
General
