Diagnostic Information And Procedures; Ignition System Symptom Diagnosis; Reference Waveform Of Ignition System; Ignition System Check - Suzuki SX4 Service Manual

1H-4 Ignition System:

Ignition System Symptom Diagnosis

Condition
Engine cranks, but will
not start or hard to start
(No spark)
Poor fuel economy or
engine performance

Reference Waveform of Ignition System

Refer to "Reference waveform No.5", "Reference waveform No.6" and "Reference waveform No.7" under "Inspection
of ECM and Its Circuits in Section 1A" for waveform of Ignition trigger signal.

Ignition System Check

Step
1 Was "Engine and Emission Control System Check"
performed?
2

Ignition spark test

1) Check all spark plugs for condition and type referring to
"Spark Plug Inspection".
2) If OK, perform ignition spark test referring to "Ignition
Spark Test".
Is spark emitted from all spark plugs?
3 DTC check
1) Perform DTC check referring to "DTC Check in Section
1A".
Is DTC stored in ECM?
4 Electrical connection check
1) Check ignition coil assemblies and high-tension cords
for electrical connection.
Are they connected securely?
5 High-tension cords check
1) Check high-tension cord for resistance referring to
"High-Tension Cord Inspection".
Is check result satisfactory?

Diagnostic Information and Procedures

Possible cause
Blown fuse for ignition coil
Loose connection or disconnection of
lead wire or high-tension cord(s)
Faulty high-tension cord(s)
Faulty spark plug(s)
Faulty ignition coil
Faulty CKP sensor or CKP sensor plate Clean, tighten or replace.
Faulty CMP sensor or sensor rotor tooth
of camshaft
Faulty ECM
Incorrect ignition timing
Faulty spark plug(s) or high-tension
cord(s)
Faulty ignition coil assembly
Faulty CKP sensor or CKP sensor plate Clean, tighten or replace.
Faulty CMP sensor or sensor rotor tooth
of camshaft
Faulty knock sensor
Faulty ECM
Action
Correction / Reference Item
Replace.
Connect securely.
Replace.
Replace.
Replace ignition coil assembly.
Clean, tighten or replace.
Replace.
Check related sensors and CKP sensor plate.
Adjust, clean or replace.
Replace.
Clean, tighten or replace.
Replace.
Replace.
Yes
Go to Step 2.
Go to Step 12.
Go to applicable DTC
diag. flow.
Go to Step 5.
Go to Step 6.
S7RW0A1804001
S7RW0A1804002
S7RW0A1804003
No
Go to "Engine and
Emission Control
System Check in
Section 1A".
Go to Step 3.
Go to Step 4.
Connect securely.
Replace high-tension
cord(s).