Suzuki Engine 2002 GRAND VITARA SQ625, Service Manual

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IGNITION SYSTEM (FOR G16 ENGINE) 6F1-5
Diagnosis
Diagnostic Flow Table
Condition Possible Cause Correction
Engine cranks, but will
not start or hard to
start No spark
• Blown fuse for ignition coil
Replace.
• Loose connection or disconnection of lead
wire or high-tension cord(s)
Connect securely.
• Faulty high-tension cord(s) Replace.
• Faulty spark plug(s) Adjust, clean or replace.
• Faulty ignition coil assembly(s) Replace.
• Faulty CMP sensor Clean, tighten or replace.
• Faulty ECM (or PCM) Replace.
Poor fuel economy or
engine performance Incorrect ignition timing Adjust ignition timing if adjustable
or check system related sensor.
Faulty high-tension cord(s) Replace.
Faulty spark plug(s) Adjust, clean or replace.
Faulty ignition coil assembly(s) Replace.
Faulty CMP sensor Clean, tighten or replace.
Faulty ECM (or PCM) Replace.
Step Action Yes No
1 Was “Engine Diagnostic Flow Table” in Section
6 performed? Go to Step 2. Go to “Engine Diagnostic
Flow Table” in Section 6.
2 Ignition Spark Test
1) Check all spark plug for condition and type,
referring to “Spark Plug” in this section.
2) If OK, perform ignition spark test, referring
to “Ignition Spark Check” in this section.
Is spark emitted from all spark plugs?
Go to Step 10 on the next
page. Go to Step 3.
3 Diagnostic Trouble Code (DTC) Check
1) Check DTC stored in ECM (or PCM), refer-
ring to “Diagnostic Trouble Code (DTC)
Check” in Section 6.
Is DTC stored?
Go to applicable DTC
Diag. Flow Table in Sec-
tion 6. Go to Step 4.
4 Electrical Connection Check
1) Check ignition coil assemblies for electrical
connection.
Are they connected securely?
Go to Step 5. Connect securely.
5 High-tension Cord Check
1) Check high-tension cord for resistance,
referring to “High-tension Cord” in this sec-
tion.
Is check result satisfactory?
Go to Step 6. Replace high-tension
cord(s).
6 Ignition Coil Assembly Power Supply, Ground
and Trigger Signal Circuits Check
1) Check these circuits for open and short.
Are circuits in good condition?
Go to Step 7. Repair or replace.